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Electrics and electronics

Problems with the electrical wiring: symptoms, cost and affected models

We have documented 93 faults with the electrical wiring in 11 engines and 77 cars, affecting 130 models of car in our database. The most important by severity and frequency: additional turbo coolant pump with a risk of short circuit and fire (BMW N62 / N63), short circuit from badly routed wiring that can prevent gear shifting (KBA campaign, 2010-2015) (Alfa Romeo Giulietta) and risk of short circuit and fire due to moisture in electrical components (Audi A4 B9).

Documented faults
93
58 of high or critical severity
Engines
11
with at least one fault on this part
Affected models
130
car generations in our database
Garage repair
No data
No reliable published costs

10 sourcesHow we work

How it works and why it fails

Wiring, connectors and short circuits

A modern car has kilometres of wires and hundreds of connectors. Chafing against moving parts, moisture or an incorrectly rated fuse can cause intermittent faults that are hard to find and, in some cases, short circuits with a fire risk that have led to recalls.

What to do

If several warnings appear and disappear at the same time, suspect a connector or a wiring loom before each part separately. If you smell burning plastic or there is smoke, stop the car and disconnect the battery if it is safe to do so. Use the VIN to check for outstanding campaigns.

General explanation by MotorFiable. The specific faults of each engine and car, with their sources, are on the linked pages.

Common symptoms

The symptoms that come up most often in the documented faults with the electrical wiring. Open each one to see what other faults cause it.

Problems with the electrical wiring by engine

From most to least important (severity × frequency). Each page details the affected versions and years, symptoms, cost and how to check for it.

  1. 1Critical severityOccasionalFrequency: OccasionalBMW N62 / N63Additional turbo coolant pump with a risk of short circuit and fireIn 2011 BMW recalled 5, 6 and 7 Series, X5 and X6 models built between 2007 and 2011 because of the additional turbo coolant pump: moisture, a short circuit and, in extreme cases, a fire. In 2012 there was another campaign for a crack in the pump, with a more robust version.
  2. 2High severityOccasionalFrequency: Occasional1.3 TCeBlown fuel pump fuseOn the Renault Captur II and Clio V with the 1.3 TCe engine, a 20-amp fuse can blow and leave the car without an engine. According to L'argus, in April 2021 this fault still had no factory fix; the official service centre's diagnosis includes checking, and sometimes replacing, the catalytic converter.
  3. 3High severityOccasionalFrequency: OccasionalM264/M254Poorly tightened 48 V earth wiring in the mild-hybrid system (fire risk)Mercedes-Benz has issued several recalls (2022-2025) because the 12 V and 48 V earth connections of some cars with a 48 V system may be poorly tightened: resistance rises, the connection heats up and a fire cannot be ruled out. The official workshop checks them and repairs them if necessary in an hour or more.
  4. 4High severityOccasionalFrequency: Occasional1.9 TDIUnit injector tappet wear and injector wiring damageOn the unit injector system, the tappets that operate the injectors can wear if the oil is not changed on time, and the injector wiring can be damaged by contact with oil, causing misfires or loss of power.
  5. 5Medium severityCommonFrequency: CommonM111Camshaft adjuster oil leak into the wiringYes: the magnet (solenoid valve) of the M111 camshaft adjuster can lose its seal, and the oil creeps up by capillary action to the connector and the wiring loom. Mercedes-Benz has the same repair cable as for the M271 (part number A2711502733), which is cheap to fit.
  6. 6Medium severityCommonFrequency: CommonM271Oil leaking from the camshaft adjuster solenoids into the wiringYes: the camshaft adjuster solenoids (magnets) of the M271 can lose their seal, and the oil wicks up to the connector and the wiring loom, and can even reach the control unit. Mercedes-Benz has a specific repair cable (reference A2711502733) that is cheap to fit.
  7. 7Medium severityCommonFrequency: CommonM270/M274Oil leaking from the camshaft adjuster into the electrical connector (M274)Yes: on the M274, the camshaft adjuster solenoids can lose their seal over the years and let oil wick up to the connector and the wiring harness, potentially reaching the ECU. It is fixed relatively cheaply with a specific repair cable.
  8. 8Medium severityOccasionalFrequency: Occasional1.0 EcoBoostMisfires and engine warning light caused by the wiring harnessFord documented in a technical service bulletin that the engine wiring harness can rub against the exhaust heat shield on the 2018-2019 automatic EcoSport, which turns on the engine warning light with misfire fault codes. Spark plugs and coils are also common wear items on this turbocharged three-cylinder.
  9. 9Medium severityOccasionalFrequency: OccasionalSubaru bóxerShort-circuiting ignition coils on the Forester, XV and Impreza (2016-2019)Two British campaigns (2020 and 2021) affect 2,338 Forester, XV and Impreza cars built from September 2016 to October 2019: one reprograms the control unit because the coil stays powered after the engine is switched off, and the other replaces all the coils, which can short-circuit and leave the car unable to start.
  10. 10High severityRareFrequency: Rare2.3 MultiJetFractured EGR pipe with a risk of short circuit and fireOn some Euro 6 Ducato built between February 2016 and September 2017, the EGR pipe could break and touch the alternator, with a risk of short circuit, loss of battery voltage and, according to the European alert, fire. Fiat checked it in a preventive campaign.
  11. 11High severityRareFrequency: Rare2.3 dCi (M9T)Fuel pipe rubbing against the wiring harness (recall 0EC1)In July 2024 Renault recalled 35,039 Master 2.3 dCi vans built from 23-09-2014 to 27-09-2023 because of possible rubbing of the fuel pipe, which could leak. The fix is a spacer.

Engines with faults with the electrical wiring

Problems with the electrical wiring by car

Faults documented on specific cars, which occur with any engine. From most to least important.

  1. 1Critical severityOccasionalFrequency: OccasionalAlfa Romeo GiuliettaShort circuit from badly routed wiring that can prevent gear shifting (KBA campaign, 2010-2015)Yes: according to Germany's KBA, on Alfa Romeo Giulietta cars built between 2010 and 2015 inadequate cable routing could cause a short circuit and, as a result, gear-shift failure.
  2. 2Critical severityOccasionalFrequency: OccasionalAudi A4 B9Risk of short circuit and fire due to moisture in electrical componentsAudi recalled A4 B9 units built between May 2017 and March 2020 because moisture can seep into an electrical component and cause a short circuit, with a risk of the vehicle catching fire.Repair: €0
  3. 3Critical severityOccasionalFrequency: OccasionalAudi Q5 IIRisk of short circuit and fire from moisture in electrical componentsAudi recalled Q5 II cars built between May 2017 and March 2020 because moisture can get into an electrical component and cause a short circuit, with a risk of the vehicle catching fire.Repair: €0
  4. 4Critical severityOccasionalFrequency: OccasionalBMW Serie 3 G202025 campaign for corrosion of the starter motor relay (risk of fire)Yes: in September 2025 BMW recalled, among other models, the 2019 to 2021 330i (G20) because the starter motor relay can corrode, overheat and cause a short circuit with a risk of fire even when the car is parked.
  5. 5Critical severityOccasionalFrequency: OccasionalBMW Serie 5 G30Two successive campaigns over a fire risk in the starter motor relay (2025 and 2026)Yes: BMW recalled the 5 Series G30 twice for the same risk in the starter motor relay - which can corrode or build up deposits, overheat and cause a short circuit with a risk of fire - first in September 2025 and again in July 2026 for more recent cars.
  6. 6Critical severityOccasionalFrequency: OccasionalBMW X3 G01Two successive campaigns for a fire risk in the starter motor relay (2025 and 2026)Yes: BMW recalled the X3 G01 twice for the same risk in the starter motor relay, which can corrode or build up deposits, overheat and cause a short circuit with a risk of fire, first in September 2025 and again in July 2026 for more recent cars.
  7. 7Critical severityOccasionalFrequency: OccasionalCupra FormentorFront airbag wiring faultYes: in June 2022 Cupra recalled more than 10,000 Formentors over a problem with the front airbag wiring, which could stop it working properly in a crash. The inspection and, where needed, the wiring repair were carried out free of charge at official dealers.Repair: €0
  8. 8Critical severityOccasionalFrequency: OccasionalCupra LeónDefective fuse in the high-voltage battery of the Cupra Leon e-Hybrid (risk of short circuit and fire)Yes: Seat recalled 16,210 Cupra Leon and Formentor e-Hybrids built between 10 October 2020 and 28 February 2022, because a defective fuse can cause an electric arc and a fire in the event of a short circuit. The fix is to install an insulating sheet.
  9. 9Critical severityOccasionalFrequency: OccasionalDacia Duster IIIPoorly secured R107 connector next to the pedals on the Duster IIIAccording to the fiches-auto.fr entry, campaign 0EFZ corrects a poorly secured electrical connector (R107) near the pedals, which the driver's foot can pull apart, causing the loss of several functions (drive, power steering, airbags, parking sensors).
  10. 10Critical severityOccasionalFrequency: OccasionalDS DS 3 CrossbackRisk of a short circuit in the 12 V battery under the bonnet (built February-July 2020)DS recalled DS3 Crossbacks built between February and July 2020 because a short circuit can occur in the 12 V battery under the bonnet, which increases the risk of fire while charging or driving.
  11. 11Critical severityOccasionalFrequency: OccasionalFiat FreemontIncorrectly installed steering wheel wiring: short circuit and risk of unintended driver airbag deploymentYes: an EU alert notified by Germany in November 2017 (44/2017) warns that, on Freemont cars built between October 2010 and April 2015, incorrectly installed steering wheel wiring can chafe and cause a short circuit, with a risk of the driver's airbag deploying while the car is being driven.
  12. 12Critical severityOccasionalFrequency: OccasionalFiat Scudo IIIBattery positive cable routed badly next to the starter motor: risk of electrical arcing and fireAccording to car-recalls.eu (July 2026), Germany's KBA lists a recall of 2,076 Scudos built between 15 October 2025 and 22 January 2026: the battery positive cable may rub against the starter motor housing, causing electrical arcing and a short circuit. It is protected with tape and corrugated tubing.
  13. 13Critical severityOccasionalFrequency: OccasionalFord TransitWiring damaged by insufficient clearance from the transmission housing: power steering failure and fire riskRecall 25SC5 covers 9,121 Transits built between 10 May 2024 and 11 November 2025: the wiring harness sits too close to the transmission housing and can be damaged, with a risk of power steering failure and a fire caused by a short circuit.
  14. 14Critical severityOccasionalFrequency: OccasionalMazda MX-5 IVDC/DC converter control unit fault with risk of short circuit and fireA 2018 Safety Gate alert covers MX-5 ND models built between August 2014 and April 2017: the DC converter control unit could fail, cause a short circuit and damage the converter, with a risk of fire. It is a precautionary recall; check the chassis number at the official service centre.
  15. 15Critical severityOccasionalFrequency: OccasionalMercedes-Benz CLS C257Gearbox wiring harness connector with moisture: risk of short circuit and fireYes: the Mercedes campaign (codes 1595003 and 1595004; Safety Gate alert A12/01979/24) covers 57,988 vehicles worldwide — E-Class, E-Class Coupé/Cabriolet, CLS and AMG GT 4-door built between 7 June 2017 and 20 April 2022 — because of a poorly processed gearbox harness connector that can let moisture in.
  16. 16Critical severityOccasionalFrequency: OccasionalMercedes-Benz CLS C25748 V earth cable bolt poorly secured: risk of fireYes: Safety Gate alert A12/00463/24 (Mercedes code 5491318) affects 75,159 vehicles worldwide — CLS, E-Class and AMG GT 4-door built from 1 July 2021 to 6 April 2023 — because the 48 V earth cable bolt, in the engine bay, may be poorly secured and overheat.
  17. 17Critical severityOccasionalFrequency: OccasionalMercedes-Benz GLC X254Incorrectly reworked fuse box: contact faults, wrong fuses and fire riskYes: Safety Gate alert SR/02431/25 (codes 8297014 and 8297015) affects 4,652 vehicles worldwide across nine model series, including the GLC, built between 31 January and 17 October 2023: a badly reworked fuse box can lose contact or carry fuses of the wrong rating and leave key systems without function.
  18. 18Critical severityOccasionalFrequency: OccasionalOpel Astra JFire risk from a short circuit in the radiator cooling fanYes: in 2014 Opel recalled around 60,000 Astra J/GTC cars from 2010-2012 because a deviation in the electrical design could cause a short circuit if the cooling fan seized, with a risk of fire.
  19. 19Critical severityOccasionalFrequency: OccasionalOpel CrosslandRisk of short circuit from chafing of the electrical wiring harness (units up to 2018)fiches-auto.fr documents a campaign on Crossland X units built up to 2018 in which the electrical wiring harness chafing against another component could cause a short circuit and, in the worst case, a fire.
  20. 20Critical severityOccasionalFrequency: OccasionalOpel Grandland IWiring chafing under the seat with a risk to the side airbag and of a short circuit (2024 build)fiches-auto.fr documents a campaign on Grandland X models built between March and November 2024 in which the wiring under the seat can chafe and become damaged, causing incorrect operation of the side airbag and a risk of short circuit and fire.
  21. 21Critical severityOccasionalFrequency: OccasionalPeugeot RCZFire risk from a short circuit in the heating resistor near the fuel lineAccording to the fiches-auto.fr page, a campaign was announced in October 2015 over the risk of a short circuit in a heating resistor close to a fuel line, affecting 61,295 vehicles across the group, including the RCZ.
  22. 22Critical severityOccasionalFrequency: OccasionalSeat León IVRisk of short circuit and fire from an incorrectly sized fuse in the Leon e-Hybrid (2020-2022)Yes: on the Leon e-Hybrid (plug-in hybrid) built between 2020 and 2022, insufficient insulation in the high-voltage battery junction box may cause a short circuit, with a risk of fire. Seat fits a protective insulating sheet as the fix under an official campaign.Repair: €0
  23. 23Critical severityOccasionalFrequency: OccasionalVolkswagen Golf VIIIRisk of short circuit and fire from an incorrectly specified fuse on the plug-in hybrid versions (eHybrid/GTE)Yes: an incorrect fuse specification in the high-voltage battery junction box of the Golf 8 eHybrid and GTE can cause a short circuit, with a risk of electric shock or fire. Volkswagen is fitting a protective insulating sheet over the box as the fix, under an official campaign.Repair: €0
  24. 24High severityOccasionalFrequency: OccasionalBMW Serie 3 E90Battery positive cable connector failureBMW recalled 2006-2011 petrol and 2009-2011 diesel 3 Series E90 cars over a faulty battery positive cable connector that can cause an electrical and engine failure, according to gebrauchtwagenberater.de.Repair: €0
  25. 25High severityOccasionalFrequency: OccasionalBMW Serie 5 E60Positive battery cable badly secured, with risk of overheating and fireBMW recalled the 5 Series E60 in May 2012 because the cover over the positive battery connection could be badly fitted, making it more likely to work loose, with excessive electrical resistance, starting problems and a risk of fire.
  26. 26High severityOccasionalFrequency: OccasionalCitroën Xsara PicassoAirbag warning light on due to connectors under the seats, and a recall on the first models (2000)The Xsara Picasso's airbag warning light comes on fairly often because of faulty connectors under the seats or intermittent faults in the control unit; Citroën also ran a recall in 2000 on airbag control on the first models.
  27. 27High severityOccasionalFrequency: OccasionalFiat Doblò ISteering column wiring that chafes and can set off the driver's airbagA campaign from April 2002 recorded in the United Kingdom (DVSA R/2002/080, Fiat reference 4427) affected 1,522 early-series Doblòs: the wiring harness can chafe against the steering column and cause the driver's airbag to deploy unintentionally. It appears in the British register and we have not been able to confirm its scope in Spain.
  28. 28High severityOccasionalFrequency: OccasionalFord Focus IVThe engine wiring harness can rub against the gearbox and cause a short circuitFord recalled Focus IV cars three times between 2020 and 2021 because the engine wiring harness could rub against a bolt or stud on the gearbox casing, with a risk of a short circuit; a third campaign also corrected vehicles in which the first repair had been done incorrectly.
  29. 29High severityOccasionalFrequency: OccasionalFord Transit CustomDual-battery positive cable incorrectly fitted, with loss of power and risk of overheatingCampaign 20S03 covers Transit Custom built from 20 May to 10 October 2019: the dual-battery positive cable may have been fitted incorrectly and come loose, with loss of engine power or even localised overheating with melting of components. Safety Gate labels it as a fire of electronic origin.
  30. 30High severityOccasionalFrequency: OccasionalHyundai Kona IIRecall over 12 V battery wiring in a frontal collisionHyundai recalled Kona IIs built between April and December 2023 because the 12 V battery wiring could come into contact with the engine control unit bracket in a frontal collision, with a risk of short circuit; in Spain it affected about 3,600 units and is fixed with a free check of about 50 minutes.
  31. 31High severityOccasionalFrequency: OccasionalMercedes-Benz Citan W415Unintended tailgate opening from moisture in the reversing camera wiring harnessYes: on Citans with a reversing camera built between 25 February 2015 and 16 November 2020, moisture could get into the camera wiring harness and make the tailgate open by itself, even while driving. There is a recall; it does not affect every car.
  32. 32High severityOccasionalFrequency: OccasionalMercedes-Benz Clase C W205Wiring harness rubbing against the driveshaft (risk of loss of drive)Yes: the German KBA registered a campaign in 2023 for the C-Class W205 because a wiring harness of the wrong length can rub against the driveshaft, wear through and cause a loss of drive. The manufacturer has not recorded any accidents because of this.
  33. 33High severityOccasionalFrequency: OccasionalMercedes-Benz Clase C W206Wiring harness with a faulty connection that can cause loss of propulsionMercedes-Benz has recalled C-Class W206 units because an incorrect connection in a wiring harness can generate high electrical resistance and, in the worst case, a sudden loss of propulsion.
  34. 34High severityOccasionalFrequency: OccasionalMercedes-Benz Clase C W206Incorrectly installed fuse box that can affect critical systemsMercedes-Benz has recalled C-Class W206 units built in 2023 because an incorrect installation of the fuse box can cause power cut-outs or leave critical vehicle systems without adequate protection.
  35. 35High severityOccasionalFrequency: OccasionalMercedes-Benz Sprinter 906Overheating of the air suspension compressor fuse holderAlert A12/1326/19 warns that the fuse holder of the air suspension compressor and its cables can overheat and increase the risk of fire. It covers Sprinters built between September 2009 and August 2018; by its nature it only concerns units with air suspension.
  36. 36High severityOccasionalFrequency: OccasionalMercedes-Benz Vito W639Starter motor wiring harness fitted the wrong way round that can touch the exhaust manifold (March to September 2006)On Viano models built between March and September 2006, the starter motor wiring harness may have been fitted twisted and sit too close to the exhaust manifold, with a risk of it burning. A known-problems sheet lists it; it is a single source.
  37. 37High severityOccasionalFrequency: OccasionalMitsubishi ASX IOverheating of the engine control unit power relayThe relay that powers the engine control unit on 2015 ASX cars can overheat and fail; the power supply is then cut, the engine warning light comes on and the car may stall and not restart. Mitsubishi corrected it with a recall that replaces the relay (Safety Gate A12/0099/18).
  38. 38High severityOccasionalFrequency: OccasionalMitsubishi LancerOverheating of the engine control unit relay and the valve lift control relayA Safety Gate alert from October 2018 (A12/1462/18) states that the engine control unit relay or the valve lift control relay can heat up abnormally and the engine can stall while driving. It covers the 2015-2016 Lancer and Lancer Sportback, and also Outlander models.
  39. 39High severityOccasionalFrequency: OccasionalMitsubishi Outlander IIIOverheating of the engine control unit power relayThe engine control unit relay (or the valve lift control relay) on the 2014-2017 Outlander and Outlander PHEV can heat up abnormally and fail; the engine may stop working and not restart. Mitsubishi put it right with a recall that replaces the relay (Safety Gate A12/1462/18).
  40. 40High severityOccasionalFrequency: OccasionalSeat Alhambra IIStarter motor relay spring wrongly positioned: risk of overheatingA 2018 Safety Gate alert covers the Alhambra, Altea, Leon and Ibiza built from 18-03 to 28-05-2011: the starter relay spring could be wrongly positioned, overheat the relay and cause a fire.
  41. 41High severityOccasionalFrequency: OccasionalŠkoda KaroqSeat frames with a manufacturing defectIn July 2019, Škoda recalled part of the Karoq production run because the seat frames had a manufacturing defect.Repair: €0
  42. 42High severityOccasionalFrequency: OccasionalVolvo S40 IIWasher fluid leaking from the windscreen washer pump into the wiring and central electronic module on the Volvo S40Washer fluid can seep into the pump, run down the wires to the central electronic module and affect several functions of the car or, in serious cases, cause a fire. UK campaign R/2011/163 covers the C30, S40, V50 and C70 and replaces the pump's wiring harness.
  43. 43High severityOccasionalFrequency: OccasionalVolvo V50Washer fluid leaking from the windscreen washer pump into the wiring and central electronic module on the Volvo V50Washer fluid can seep into the pump, run down the wires to the central electronic module and affect several functions of the car or, in serious cases, cause a fire. UK campaign R/2011/163 covers the C30, S40, V50 and C70 and replaces the pump's wiring harness.
  44. 44Medium severityCommonFrequency: CommonBMW Serie 3 E46Central locking and immobiliser failure due to worn relaysThe central locking can become intermittent or stop responding to the remote, and the immobiliser can fail sporadically when starting; gebrauchtwagenberater.de attributes both faults to wear in the relays of the control modules, and fiches-auto.fr records numerous testimonies of unreliable locking.
  45. 45Medium severityCommonFrequency: CommonPeugeot 206Cascading electrical warnings caused by the BSI (fuse box)When the BSI (the fuse and relay box that centralises much of the electrical system) receives an unstable signal, several warning lights can come on at once with no mechanical fault behind them; it is usually due to a corroded earth, damp connectors or a weak battery.
  46. 46Critical severityRareFrequency: RareMazda CX-3A DC converter fault can cause a short circuit and a fire riskOn cars built up to April 2017, the control unit of the DC converter can malfunction and cause a short circuit that damages the converter itself, with a risk of fire. Mazda corrects it by checking the component at an official dealer.
  47. 47Critical severityRareFrequency: RareMercedes-Benz Clase E W212Short-circuit risk from moisture in conductive componentsMercedes-Benz recalled a range of vehicles, including the last E-Class W212 cars, because moisture in certain conductive components can cause a short circuit.
  48. 48Critical severityRareFrequency: RareMercedes-Benz Clase E W213Short-circuit risk from moisture in the wiring harness connectorsA specialist reliability listing records a Mercedes-Benz recall for E-Class W213 cars built between 2017 and 2022 over a risk of short circuit due to water getting into the wiring harness connectors.
  49. 49Critical severityRareFrequency: RareSuzuki Swift VRisk of short circuit and fire from the 12 V positive cableIn a very small run of 2022 cars, the 12 V positive cable can touch the bodywork or the negative wiring and cause a short circuit with a risk of fire. Suzuki recalled 465 vehicles worldwide (Swift and Ignis) in March 2022.
  50. 50Critical severityRareFrequency: RareToyota Yaris IIThe driver's window switch can short-circuit and catch fireA 2015 recall covered Yaris built between 2005 and 2010 because the master window switch on the driver's side could short-circuit, overheat and, in the worst case, cause a fire.
  51. 51Medium severityOccasionalFrequency: OccasionalAlfa Romeo GiuliettaTailgate wiring breakage from use (third brake light and number plate light)According to a German used-car guide, repeatedly opening and closing the Giulietta's tailgate fairly often breaks a wire in its harness, which can leave the third brake light or the number plate light not working.
  52. 52Medium severityOccasionalFrequency: OccasionalAudi A3 IVFaulty fuses on the plug-in hybrid A3 (TFSIe)In April 2022, Audi recalled 3,656 plug-in hybrid A3 (TFSIe) cars built between October 2020 and February 2022 because of a manufacturing defect in the fuses.Repair: €0
  53. 53Medium severityOccasionalFrequency: OccasionalAudi A3 IVPossible power supply failure on more than 100,000 carsIn August 2023, Audi recalled more than 100,000 A3 cars built between March 2020 and May 2023 because of a possible power supply failure.Repair: €0
  54. 54Medium severityOccasionalFrequency: OccasionalBMW i3Charger and charging socket fault on the BMW i3According to fiches-auto.fr, 5 of the 14 i3 testimonials mention charging problems: a charger that failed after about 800 charges (120,000 km) on the 170 hp electric version and a socket fault at 49,000 km, covered by warranty.
  55. 55Medium severityOccasionalFrequency: OccasionalBMW X5 E70Electronic module and connector faults caused by moisture on the X5 E70According to fiches-auto.fr, the X5 E70's electronics appear in 14 mentions out of 152 testimonies: DSC, ABS, airbag and cruise control faults, attributed to moisture and corroded connectors; one case cites a €1,300 module at around 90,000 km.
  56. 56Medium severityOccasionalFrequency: OccasionalCitroën C5 IIShort-circuit risk from rubbing of the starter motor cable (2015-2016 production)An EU alert (RAPEX A12/0997/17) covers C5s built between 30 June 2015 and 29 April 2016 in which the starter motor terminal was incorrectly positioned and could rub against the EGR valve, damaging the cable insulation and creating a risk of a short circuit.
  57. 57Medium severityOccasionalFrequency: OccasionalCitroën C8Repeated electronic faults in the BSI control unit and wiringThe fiches-auto.fr page counts 27 C8 owner reports of repeated electronic faults (BSI, automatic lights, controls); cars from 2002-2005 would be the most exposed to damp-related faults.
  58. 58Medium severityOccasionalFrequency: OccasionalCitroën XsaraIntermittent faults caused by the door and boot wiring looms on the Citroën XsaraAccording to fiches-auto.fr, the Xsara's door and boot looms cause around 54 mentions of intermittent electrical faults (locking, instrument cluster, lights, wipers), made worse by damp. No public recall is recorded.
  59. 59Medium severityOccasionalFrequency: OccasionalFord B-MaxPoor durability of the mechanism, locks and wiring of the rear sliding doorsfiches-auto.fr notes that the mechanism, locks and wiring of the B-Max's rear sliding doors may not be durable enough; Auto Express adds that, because the doors are heavy, they can close by themselves if the car is parked on a steep slope.
  60. 60Medium severityOccasionalFrequency: OccasionalFord C-Max IRear wiper motor short circuit caused by water ingress (2003-2005)On cars built between 2003 and 2005, insufficient sealing of the rear wiper control housing lets water in and can cause a short circuit, according to two independent sources.
  61. 61Medium severityOccasionalFrequency: OccasionalMazda 3 IIIWiper failure caused by corrosion in an electrical connectorYes: Mazda recalled Mazda3 BM cars built between July 2015 and July 2017 because a deposit of metal particles in a connector can interrupt the current feeding the wiper motor and leave the wipers not working.
  62. 62Medium severityOccasionalFrequency: OccasionalNissan Leaf IILocking and communication faults in the CHAdeMO rapid charging connectorSome Leaf IIs have locking or communication defects in the CHAdeMO rapid charging socket, with charging interruptions, refusal to start the session or stops before charging is complete.
  63. 63Medium severityOccasionalFrequency: OccasionalOpel Meriva AWiring breaks in the tailgate with cascading electronic faultsOn the Meriva A's tailgate, the wiring can break and lead to a series of cascading electronic faults (rear brake light, rear wiper, lock, among others), according to Gebrauchtwagenberater.de.
  64. 64Medium severityOccasionalFrequency: OccasionalPeugeot 207Cascading electrical warnings from the BSI (fuse box)When the BSI (the fuse and relay box that centralises the electrical system) receives an unstable signal, several warning lights (ABS, ESP, airbag...) can come on at once without any mechanical fault behind them; it is usually down to a corroded earth, damp wiring or a weak battery.
  65. 65Medium severityOccasionalFrequency: OccasionalRenault Clio IIIAirbag warning light on because of a connector under the seatsThe airbag warning light comes on unexpectedly on some Clio IIIs because of a connectivity problem in the wiring under the front seats; repairing or soldering that connection usually fixes it, according to Caradisiac.
  66. 66Medium severityOccasionalFrequency: OccasionalRenault Mégane E-TechAC and DC charging faults on the Mégane E-Tech (on-board charger and connector)According to the fiches-auto.fr testimonies, charging is the most repeated electrical fault: 20 of the 86 testimonies mention charging that stops or is refused on AC (22 kW charger) or rapid charging, with 'charging impossible' warnings.
  67. 67Medium severityOccasionalFrequency: OccasionalŠkoda Fabia IEngine wiring harness corrosion from water collecting around itOn Fabia I units from before the 2004 facelift, the engine wiring harness sits in a recess in the bodywork where water collects, which can cause faults with the central locking, the windows and the wipers; the manufacturer's 97J7 service campaign should already have corrected it on most vehicles, according to gebrauchtwagenberater.de.
  68. 68Medium severityOccasionalFrequency: OccasionalŠkoda Superb IIIElectrical fault caused by a poorly secured cable clampAt the end of 2015, Volkswagen-Audi recalled Superb III models from 2015-2016 because a clamp holding a cable could come loose and cause faults in the car's electronic functions.Repair: €0
  69. 69Medium severityOccasionalFrequency: OccasionalTesla Model YRisk of a short circuit in the central computer (Hardware 4.1) that can leave the reversing camera without an imageOn Model Y cars with the Hardware 4.1 computer (built 2023-2025), a reverse current when the car is switched on can cause a short circuit on the central computer board and leave the reversing camera without an image; Tesla fixes it with a software update or, if needed, by replacing the board.
  70. 70High severityRareFrequency: RareCitroën C-CrosserCorrosion of the electric seat connectors under the rear matIn 2011 the DVSA registered a campaign (R/2011/015) because on some versions of the Citroën C-Crosser with electric front seats, the unused power connectors were left under the rear mat and could corrode from water or salty snow and heat up locally. The cables are relocated higher up, on the seat structure.
  71. 71High severityRareFrequency: RarePeugeot 4007Corrosion of the electric seat connectors under the rear floor matIn 2011 the DVSA recorded a campaign (R/2011/014) because on some Peugeot 4007 versions with electric front seats, the unused power connectors were left under the rear floor mat and could corrode with water or salted snow and heat up locally. The cables are relocated higher up, on the seat structure.
  72. 72High severityRareFrequency: RarePeugeot 508 IStarting system faults: starter motor and wiring (2013-2017 production)Two campaigns cover the 508 I starting system: one from 2017 (ref. R2017215) over a starter motor power cable that could rub and wear through, on vehicles built between October 2013 and April 2017; and another, also from 2017 (ref. R2017140), over a starter motor that might not work properly, on vehicles from May-October 2016.
  73. 73High severityRareFrequency: RareToyota Prius IVA short circuit can occur in the instrument cluster (July 2019 batch)In a very specific range of ZVW50/ZVW55 units built between 12 and 31 July 2019 (about 239 units), an electrical short circuit can occur in the instrument cluster, making the speedometer, odometer or fuel gauge fail. Toyota recalled these units in 2020.
  74. 74Medium severityRareFrequency: RareMercedes-Benz Clase A W176Fuse box incorrectly installed in a 2016 production periodMercedes-Benz recalled a batch of A-Class cars built between March and April 2016 because the fuse box might not have been installed correctly.
  75. 75Medium severityRareFrequency: RareNissan Micra IIIAirbag warning light comes on because of a faulty connectorOn some Micra III cars, a faulty connector in the airbag system can switch on the corresponding warning light on the dashboard without there being a mechanical problem in the airbag itself.
  76. 76Medium severityRareFrequency: RareOpel Vivaro BMain wiring harness touching the windscreen wiper mechanismThe Vivaro B's 2015 campaign included chafing between the main wiring harness and the windscreen wiper mechanism, which could prevent starting or stop the wipers unexpectedly.
  77. 77Low severityOccasionalFrequency: OccasionalDacia Duster IISide indicator failure caused by poorly protected wiringThe side indicator light can stop working because of a badly positioned connecting wire that rubs against the bodywork and wears or breaks; the replacement-part manufacturer Hella documents the fault on Dusters built between 2010 and 2018, which includes the early Duster II cars.
  78. 78Low severityOccasionalFrequency: OccasionalNissan Qashqai IISteering column wiring harness faults affecting the steering wheel controlsAutopista describes electrical faults related to the steering column wiring harness that can leave the steering wheel controls not working, especially on units with the Xtronic automatic gearbox.
  79. 79Low severityOccasionalFrequency: OccasionalNissan Qashqai IIISteering column wiring harness fault affecting the steering wheel controlsYes: the specialist press describes electrical faults in the Qashqai's steering column wiring harness that can leave the steering wheel controls (audio, phone or cruise control) not working, above all on units with the Xtronic automatic gearbox.
  80. 80Low severityOccasionalFrequency: OccasionalOpel Zafira ARear door wiring fault (windows and central locking)The wiring harness that runs to the Zafira A's rear doors can break internally and cause short circuits that leave that door's window or central locking out of action.
  81. 81Low severityOccasionalFrequency: OccasionalRenault Mégane E-TechCharging connector flap fault on the Mégane E-TechAccording to the fiches-auto.fr profile, there are testimonies of a charging connector flap that opens and closes by itself, or gets stuck without closing; the profile mentions a campaign during servicing, without detailing its scope.
  82. 82Low severityOccasionalFrequency: OccasionalŠkoda RoomsterIntermittent breaks in the front left door wiring loomfiches-auto.fr cites recurring electrical faults from the front left door wiring loom, repaired twice in one case, with intermittent breaks caused by repeated opening and moisture in the connectors.

Problems with the electrical wiring by make

Problems with the electrical wiring in your car

17 cars have several documented faults with the electrical wiring. Choose yours to see only the ones that affect them, by engine and by year.

Alfa Romeo 1
Audi 1
BMW 1
Dacia 1
Ford 1
Mercedes-Benz 8
Nissan 2
Renault 1
Škoda 1

How much it costs to repair a fault with the electrical wiring

Sorted from the most expensive repair to the cheapest. Prices in Spain including VAT (parts and labour); what each figure includes is on its page.

How we calculate costs · The most expensive repairs across all engines

OBD fault codes with the electrical wiring

The codes the ECU usually stores when this part fails: what they mean, causes and what to check.

Frequently asked questions

Which engines have the most faults with the electrical wiring?

By severity and frequency, the BMW N62 / N63 (additional turbo coolant pump with a risk of short circuit and fire, critical severity), the 1.3 TCe (blown fuel pump fuse, high severity), the M264/M254 (poorly tightened 48 V earth wiring in the mild-hybrid system (fire risk), high severity), the 1.9 TDI (unit injector tappet wear and injector wiring damage, high severity), the M111 (camshaft adjuster oil leak into the wiring, medium severity) and the M271 (oil leaking from the camshaft adjuster solenoids into the wiring, medium severity). In total we have documented 11 engines with faults with the electrical wiring.

Which cars have problems with the electrical wiring?

Among those we have analysed: Alfa Romeo Giulietta (short circuit from badly routed wiring that can prevent gear shifting (KBA campaign, 2010-2015)), Mercedes-Benz CLS C257 (gearbox wiring harness connector with moisture: risk of short circuit and fire), Audi A4 B9 (risk of short circuit and fire due to moisture in electrical components), Audi Q5 II (risk of short circuit and fire from moisture in electrical components), BMW Serie 3 G20 (2025 campaign for corrosion of the starter motor relay (risk of fire)), BMW Serie 5 G30 (two successive campaigns over a fire risk in the starter motor relay (2025 and 2026)), BMW X3 G01 (two successive campaigns for a fire risk in the starter motor relay (2025 and 2026)) and Cupra Formentor (front airbag wiring fault). In total, 77 cars with documented faults with the electrical wiring.

How much does it cost to repair a fault with the electrical wiring?

It depends a lot on the engine or car. At a dealer, from €0 to €0, including VAT, based on the 10 faults with a documented cost. The most expensive is risk of short circuit and fire due to moisture in electrical components (Audi A4 B9).

What symptoms does a fault with the electrical wiring cause?

The most frequently cited in the documented faults: intermittent electronic warnings or sensor faults, engine stalls or cuts out while driving, engine fault warning light (check engine), electric charging failure or interruption, airbag warning light on and visible oil leak.

Sources

Every fact on this page links to its source. If you find an error, let us know.

  1. 1.Fiabilité Audi A4 : pannes, rappels et témoignagesfiches-auto.fr · Reliability study · consulted 27 September 2026 · in French
  2. 2.Fiabilité Audi Q5 II : pannes, rappels et témoignagesfiches-auto.fr · Reliability study · consulted 27 September 2026 · in French
  3. 3.Used Cupra Formentor (Mk1, 2020-date) buyer's guide: stylish and family-friendlyAuto Express · Motoring press · consulted 27 September 2026
  4. 4.Seat Leon IV (seit 2020) – Bekannte Probleme & RückrufeGebrauchtwagenberater.de · Other source · published 15 December 2022 · consulted 27 September 2026 · in German
  5. 5.VW Golf 8 (CD) – Bekannte Probleme & RückrufeGebrauchtwagenberater.de · Other source · published 22 April 2022 · consulted 27 September 2026 · in German
  6. 6.BMW 3er E90/E91/E92/E93: ProblemeGebrauchtwagenberater.de · Motoring press · consulted 27 September 2026 · in German
  7. 7.Used Skoda Karoq reviewAuto Express · Motoring press · consulted 27 September 2026
  8. 8.Used Audi A3 Mk4 (2020-date) buyer's guide: classy used hatchbackAuto Express · Motoring press · consulted 27 September 2026
  9. 9.FACUA alerta de la llamada a revisión de los Skoda Superb III de 2015-2016FACUA-Consumidores en Acción · Consumer association · published 3 January 2016 · consulted 27 September 2026 · in Spanish
  10. 10.Used Skoda Superb (Mk3, 2015-2024) review and buyer's guideAuto Express · Motoring press · consulted 27 September 2026