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Suspension, steering, brakes and wheels

Problems with the brake servo: symptoms, cost and affected models

We have documented 96 faults with the brake servo in 2 engines and 87 cars, affecting 106 models of car in our database. The most important by severity and frequency: loss of braking assistance from vacuum pump damage (1.2 PureTech), blocked tandem pump filter and loss of brake assistance (Kia Sportage IV) and brake actuator failure (hard pedal, loss of assistance) (1.8 Hybrid).

Documented faults
96
96 of high or critical severity
Engines
2
with at least one fault on this part
Affected models
106
car generations in our database
Garage repair
No data
No reliable published costs

2 sourcesHow we work

How it works and why it fails

Brake servo and vacuum pump

The brake servo multiplies the force you apply with your foot on the pedal. On many engines (especially diesels and direct-injection turbo petrols) the vacuum it needs is produced by a mechanical vacuum pump; if it fails, the pedal becomes hard and you have to press much harder to brake.

What to do

If the brake pedal becomes hard or the car brakes less than normal, stop as soon as you can and do not keep driving: it is a safety fault. Use the VIN to check whether your car is included in any recall for the vacuum pump.

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 brake servo. Open each one to see what other faults cause it.

Problems with the brake servo 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 severityFrequency: Very frequent1.2 PureTechLoss of braking assistance from vacuum pump damageOn 1.2 PureTech turbos built between 2013 and 2018, belt debris can damage the vacuum pump that feeds the brake servo and reduce braking assistance. There were two free recalls (2020 and 2022); it is worth confirming they were done.
  2. 2Critical severityFrequency: Occasional1.8 HybridBrake actuator failure (hard pedal, loss of assistance)Yes, it is a documented fault on the Prius III: the diaphragm of the brake actuator's accumulator can degrade and make the pedal very hard, forcing you to brake with much more force. Toyota ran a campaign in 2013; there are also owner reports of actuators failing after the warranty had expired.

Engines with faults with the brake servo

Problems with the brake servo by car

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

  1. 1Critical severityFrequency: Very frequentKia Sportage IVBlocked tandem pump filter and loss of brake assistanceYes: a KBA campaign from October 2023 states that the tandem pump filter on Sportages built between 2018 and 2020 has a design defect that can make the brake servo fail and stiffen the brake pedal.
  2. 2Critical severityFrequency: OccasionalAlfa Romeo MiToBrake servo pipe connector fault in MiTos built in 2012A 2012 campaign affected MiTos built between 1 June and 30 September 2012: a connector on the brake servo pipe could fail and leave the brakes without vacuum assistance. The record consulted is from the United Kingdom (268 cars); we do not know how many units it affected in Spain.
  3. 3Critical severityFrequency: OccasionalAudi A6 C7Brake servo damaged by oil entering from the vacuum lines (2012 campaign)Safety Gate/RAPEX circulated in September 2014 (alert 37/2014) a recall of the Audi A6 Avant and Allroad (C7) built between March and December 2012: in isolated cases, oil can enter the brake servo through the vacuum hoses, damage the diaphragm and reduce braking force.
  4. 4Critical severityFrequency: OccasionalAudi e-tronElectromechanical brake booster failure and corrosion of the brake pressure unit (ABS/ESC)In 2021 Audi recalled two batches of the e-tron because of the electromechanical brake booster (2,303 cars, recall 47R1) and the corrosion of the brake pressure unit (361, recall 47R7). Both can affect the brake booster, the ABS and the ESC and lengthen the braking distance.
  5. 5Critical severityFrequency: OccasionalAudi e-tronBolt on the rod between the brake pedal and the brake booster that can work looseAudi first recalled a small batch of 2019 e-trons (recall 46P6) and, in 2026, about 96,000 e-trons and Q8 e-trons worldwide because of the bolted connection of the rod between the brake pedal and the brake booster, which can work loose. It is checked and tightened free of charge.
  6. 6Critical severityFrequency: OccasionalBMW Serie 2 Active Tourer U06Defective weld on the hollow shaft of the brake servo (brake system servomotor)In 2025 BMW recalled several models, including the 2 Series with type U2AT (Safety Gate alert SR/00053/25), because the hollow shaft of the brake servomotor could be poorly welded and could break under high pressure. In the United Kingdom, the DVSA counts only 3 Active Tourers built between March 2023 and July 2024.
  7. 7Critical severityFrequency: OccasionalBMW X1 U11Faulty weld on the hollow shaft of the brake servo (brake system servo motor)In 2025 BMW recalled, with a Safety Gate alert, X1 and iX1 models (and others) built between July 2022 and November 2024 because the hollow shaft of the brake servo motor could be badly welded and break under high braking pressure: the pedal would need more force, braking distances would grow and ABS and DSC would lose assistance.
  8. 8Critical severityFrequency: OccasionalBMW X5 G05Loss of brake assistance due to integrated braking system (IBS) faultBMW has recalled cars built since June 2022, the X5 among them, because the integrated braking system can unexpectedly lose its hydraulic assistance: you have to press the pedal harder, stopping distances get longer and the ABS and stability control may fail. In 2021 there was another campaign over the hydraulic unit of that system.
  9. 9Critical severityFrequency: OccasionalBMW X5 G05Faulty weld on the hollow shaft of the brake boosterIn January 2025 the Safety Gate published a BMW recall over the brake booster: its hollow shaft is not properly welded and the weld may give way under high brake pressure. It affects cars built between July 2022 and November 2024 (X5, X6 and X7 included), lengthens stopping distances and leaves the ABS and DSC without assistance.
  10. 10Critical severityFrequency: OccasionalBMW X6 G06Loss of brake assistance due to integrated braking system (IBS) faultBMW has recalled cars built since June 2022, the X6 among them, because the integrated braking system can unexpectedly lose its hydraulic assistance: you have to press the pedal harder, stopping distances get longer and the ABS and stability control may fail. In 2021 there was another campaign over the hydraulic unit of that system.
  11. 11Critical severityFrequency: OccasionalBMW X6 G06Faulty weld on the hollow shaft of the brake boosterIn January 2025 the Safety Gate published a BMW recall over the brake booster: its hollow shaft is not properly welded and the weld may give way under high brake pressure. It affects cars built between July 2022 and November 2024 (X5, X6 and X7 included), lengthens stopping distances and leaves the ABS and DSC without assistance.
  12. 12Critical severityFrequency: OccasionalBMW X7 G07Loss of brake assistance due to integrated braking system (IBS) faultBMW has recalled cars built since June 2022, the X7 among them, because the integrated braking system can unexpectedly lose its hydraulic assistance: you have to press the pedal harder, stopping distances get longer and the ABS and stability control may fail. In 2021 there was another campaign over the hydraulic unit of that system.
  13. 13Critical severityFrequency: OccasionalBMW X7 G07Faulty weld on the hollow shaft of the brake boosterIn January 2025 the Safety Gate published a BMW recall over the brake booster: its hollow shaft is not properly welded and the weld may give way under high brake pressure. It affects cars built between July 2022 and November 2024 (X5, X6 and X7 included), lengthens stopping distances and leaves the ABS and DSC without assistance.
  14. 14Critical severityFrequency: OccasionalCitroën C3 Aircross IBreakage of the brake servo vacuum pump due to insufficient lubrication (loss of brake assistance)In a wide range of C3 Aircross I cars built between February 2017 and November 2019, Citroën found that the brake servo vacuum pump may be insufficiently lubricated and break, which reduces brake assistance and stiffens the pedal.
  15. 15Critical severityFrequency: OccasionalCitroën C4 CactusBrake servo vacuum pump failure due to insufficient lubrication (loss of braking assistance)Citroën recalled C4 Cactus cars built between February 2017 and November 2019 because the brake servo vacuum pump can be insufficiently lubricated and fail, which reduces braking assistance and stiffens the pedal.
  16. 16Critical severityFrequency: OccasionalCitroën C5 AircrossBrake servo (Mastervac) diaphragm tearing from overpressure (built September-October 2019)Citroën recalled C5 Aircross cars built in September and October 2019 because overpressure can tear the diaphragm of the brake servo (Mastervac), which reduces braking assistance.
  17. 17Critical severityFrequency: OccasionalFiat Doblò IIBrake servo vacuum hose connector that can break (2012 Doblò)Fiat recalled Doblòs (and other models from the brand, such as the Qubo) built between June and September 2012 because a connector on the brake servo hose could fail and cause the vacuum assistance to be lost, forcing you to press the pedal harder. It is corrected by fitting a new hose.
  18. 18Critical severityFrequency: OccasionalFiat QuboBrake servo vacuum pipe connector that may break (2012 Qubo)Fiat recalled Qubos built between June and September 2012 because a brake servo pipe connector could fail and cause a loss of vacuum assistance, meaning more effort on the pedal. The campaign (DVSA R/2012/139) is resolved by fitting a new pipe.
  19. 19Critical severityFrequency: OccasionalFord Kuga IBrake servo vacuum pump non-return valveKuga cars built between 1 November 2008 and 12 March 2009 may have a faulty non-return valve in the brake servo vacuum pump, leaving the brake servo with insufficient assistance. A free replacement campaign took about 30 minutes.Repair: €0
  20. 20Critical severityFrequency: OccasionalFord RangerLoss of brake servo assistance, with longer pedal travel and a longer stopping distanceCampaign 225S77 covers Rangers built between 27 June 2024 and 24 June 2025: brake servo assistance may be lost, so the pedal travels further and the car needs a longer distance to stop. Safety Gate classifies it as a serious accident risk.
  21. 21Critical severityFrequency: OccasionalFord Transit CustomBrake pedal pin clip out of specification: the pedal can come away from the brake servoIn 2013 a warning was issued that the first Transit Custom vehicles (built between late September 2012 and early February 2013) had an R-clip on the brake pedal pin that did not meet the material specification and could come off, leaving the pedal disconnected from the brake servo and with no braking.
  22. 22Critical severityFrequency: OccasionalHonda FR-VBrake servo with a manufacturing defect that reduces or cancels braking assistanceOnly in a short series: in 2013 Honda recalled FR-Vs built between January and November 2006 in the UK because a manufacturing defect in the brake servo could reduce or cancel braking assistance and lengthen stopping distances. The servo is checked and replaced if necessary.
  23. 23Critical severityFrequency: OccasionalHyundai i40Loss of brake servo assistance due to the tandem vacuum pumpYes: since April 2023 the DVSA has recorded a recall (reference 21D036) for 187 British i40s built between December 2018 and May 2019, for possible loss of brake assistance. The pump's drive belt and mesh filter are inspected and the pump is replaced if defective.
  24. 24Critical severityFrequency: OccasionalHyundai ix35Possible defect in the brake servo vacuum pumpYes. In 2012 Hyundai recalled more than 2,200 ix35 units for a possible defect in the brake servo vacuum pump, the part that multiplies the force the driver applies to the brake pedal.
  25. 25Critical severityFrequency: OccasionalJeep Wrangler JLSoftware fault in brake system module with insufficient braking assistance (2021 model year)Yes: a Safety Gate alert from March 2021 (campaign Y09) covers 2021 model year Wrangler JLs, because the brake system module may have a software fault that reduces assistance in an emergency stop.
  26. 26Critical severityFrequency: OccasionalKia Optima IVBrake servo tandem vacuum pump fault due to a blocked mesh filterYes: the British DVSA recorded in 2023 a recall (references 220S15 and 221048) that includes Optimas built between October 2018 and September 2020: the tandem pump's mesh filter may become blocked, the vacuum pump may fail and braking distances may lengthen through lack of assistance.
  27. 27Critical severityFrequency: OccasionalMazda CX-5 ILoss of braking force due to brake servo vacuum pump failureYes: some first-generation CX-5s built in 2016 were recalled because the vacuum pump that boosts the brake servo can fail, which reduces the available braking force and means you have to press the pedal much harder.
  28. 28Critical severityFrequency: OccasionalMercedes-Benz Clase B W246Brake servo with reduced assistance due to a faulty vacuum pipe fittingOn cars built between April 2011 and April 2013, a faulty fitting on the brake servo vacuum pipe can reduce braking assistance, forcing you to press the pedal harder than normal.
  29. 29Critical severityFrequency: OccasionalMercedes-Benz Clase M W163Corroded brake servo on the Mercedes M-Class with possible loss of pedal connection (2004 and 2005)According to Gebrauchtwagenberater, which cites the KBA, in the 2004 and 2005 MLs corrosion of the brake servo can cut the connection between the pedal and the braking system. The check involves inspecting the servo and, if necessary, replacing parts.
  30. 30Critical severityFrequency: OccasionalMercedes-Benz Clase M W164Brake servo corrosion and the 2023 recallAccording to the fiches-auto.fr page, Mercedes launched a recall in 2023 (codes 4290005 to 4290008) for brake servo corrosion that would affect models from 2004 to 2015, including the M-Class. We have not been able to confirm it from an official source.
  31. 31Critical severityFrequency: OccasionalMercedes-Benz Clase R W251Brake servo corrosion and the 2022 recallIn 2022 Mercedes recalled around 993,000 cars worldwide, including the R-Class, because corrosion can cause a leak in the brake servo and reduce braking force. Check with the chassis number whether the recall has been done.
  32. 32Critical severityFrequency: OccasionalMercedes-Benz GL X164Brake servo corrosion and the 2022 recallIn 2022 Mercedes recalled around 993,000 cars worldwide, the GL among them, because corrosion can cause a leak in the brake servo and reduce braking force. Check with the chassis number whether the campaign has been carried out.
  33. 33Critical severityFrequency: OccasionalMercedes-Benz GL / GLS X166Brake servo corrosion and the 2022 recallIn 2022 Mercedes recalled around 993,000 cars worldwide, including the GL, because corrosion can cause a leak in the brake servo and reduce braking force. Check with the VIN whether the campaign has been carried out.
  34. 34Critical severityFrequency: OccasionalOpel Combo DBrake servo vacuum hose connector that can break (2012 Combo D)In February 2013, Vauxhall (Opel) recalled 498 Combo D models built between 4 July and 4 August 2012 in the UK because the brake servo vacuum hose connector could break, leaving the pedal hard and braking reduced. A German guide mentions almost 300 units from 2012 in Germany.
  35. 35Critical severityFrequency: OccasionalOpel CrosslandBrake servo vacuum pump failure with reduced braking assistance (built 2017-2018)Opel opened a campaign on vehicles built between April 2017 and August 2018 in which a worn belt reduces the lubrication of the brake servo vacuum pump; if it breaks, the brake pedal loses assistance and becomes very hard.
  36. 36Critical severityFrequency: OccasionalPeugeot 307Loss of brake assistance due to a vacuum pump faultA fault in the brake servo's vacuum pump valve can reduce brake assistance and make the pedal suddenly go hard; Peugeot issued several recalls between 2005 and 2010 for poor braking performance in different production batches.
  37. 37Critical severityFrequency: OccasionalSaab 9-3Brake servo valve with shorter life from heat and reduced braking effectivenessIn May 2006, 21,613 Saab 9-3s built between July 2002 and March 2005 were recalled because a brake servo valve could wear out sooner than expected due to heat in the engine bay, reducing braking effectiveness. The valve was checked and replaced if necessary.
  38. 38Critical severityFrequency: OccasionalSuzuki S-Cross ITemporary loss of brake servo assistance caused by the vacuum pump valveSuzuki recalled the S-Cross (and the Swift, Baleno and Vitara) because the non-return valve in the vacuum pump can swell and temporarily leave the brake servo without assistance: the car still brakes, but you have to press the pedal considerably harder.
  39. 39Critical severityFrequency: OccasionalSuzuki Swift VTemporary brake servo lock-up from the vacuum pump valveYes: Suzuki recalled Swifts built between 2015 and 2022 because the valve of the brake servo vacuum pump can swell and momentarily block the vacuum, forcing you to press the brake much harder. The repair is free at the official network.
  40. 40Critical severityFrequency: OccasionalSuzuki VitaraTemporary brake servo lock-up caused by the vacuum pump valveYes: Suzuki recalled Vitaras built between 2015 and 2022 because the brake servo's vacuum pump valve can swell and momentarily block the vacuum, forcing you to press the brake far harder. The repair is free at official dealers.
  41. 41Critical severityFrequency: OccasionalToyota Aygo XBrake servo vacuum valve contaminated by an incorrect lubricantToyota recalled Aygo X built between 30 June and 22 August 2022 because the brake servo could malfunction and lengthen braking distance. According to the British DVSA, an unsuitable lubricant used in manufacturing could contaminate the brake servo vacuum valve; the remedy is to replace it.
  42. 42Critical severityFrequency: OccasionalToyota CamryBrake booster pump motor failure: loss of braking assistanceYes: a 2019 European alert (A12/1199/19) covers Camrys built between 26 April and 6 June 2019, because the brake booster pump motor can stop working and the driver would lose braking assistance after several presses of the pedal.
  43. 43Critical severityFrequency: OccasionalToyota GR Supra A90Loss of braking assistance from the vacuum pumpToyota recalled Supras built between July 2018 and June 2021 because the engine software can damage the oil and vacuum pump that provides brake assistance, which would lengthen braking distances.
  44. 44Critical severityFrequency: OccasionalToyota Hilux VIIIBrake servo piston breakage with loss of braking assistanceToyota recalled Hilux cars built between August 2018 and May 2019 because, when the brake pedal is pressed repeatedly, the brake servo piston can break and leave the car without braking assistance, with a longer stopping distance. In the UK, the remedy is to check the piston's serial number and replace the piston if needed.
  45. 45Critical severityFrequency: OccasionalToyota ProAce CityBrake servo: loss of hydraulic brake compensation because of a software faultCampaign CI24-022 covers ProAce City and City Verso from 2023-2024: the CAN network may send an invalid brake servo vacuum value and deactivate the hydraulic compensation, with less braking capacity; it is corrected with a software update.
  46. 46Critical severityFrequency: OccasionalVolkswagen Passat B6Loss of brake assistance from a damaged brake servo vacuum hose (200 hp engines)According to gebrauchtwagenberater.de, on the 200 hp engines of the Passat B6 built between 2005 and 2007 a damaged vacuum hose can impair brake assistance, making the brake pedal harder.
  47. 47Critical severityFrequency: OccasionalVolvo S40 IBrake servo vacuum pump fault on the 1999-2000 Volvo S40 1.9 dieselThe brake servo vacuum pump on S40 and V40 1.9 diesels built in 1999 and 2000 may fail and leave the brake pedal heavy to press. The British campaign R/2002/053 fits a modified pump; it affected 1,551 vehicles in the UK.
  48. 48Critical severityFrequency: OccasionalVolvo S80 IIBrake servo vacuum pipe chafed by the wiper mechanism on the Volvo S80In 2012 Volvo recalled (R/2012/104 in the UK) a batch of V60, V70, XC70 and S80 cars because the wiper mechanism could chafe the brake servo vacuum pipe. If it wears through, assistance drops gradually and, in the worst case, can disappear suddenly and without warning.
  49. 49Critical severityFrequency: OccasionalVolvo V60 IBrake servo vacuum hose rubbing against the wiper armA European alert from October 2012 (A12/1474/12) warned that, in some V60 cars from model years 2012 and 2013, the wiper arm mechanism could rub against the brake servo vacuum hose. Braking assistance would be lost gradually or, in the worst case, all at once and without warning.
  50. 50Critical severityFrequency: OccasionalVolvo V70 IIIBrake servo vacuum pipe chafed by the wiper mechanism on the Volvo V70In 2012 Volvo recalled (R/2012/104 in the UK) a batch of V60, V70, XC70 and S80 cars because the wiper mechanism could chafe the brake servo vacuum pipe. If it wears through, assistance drops gradually and, in the worst case, can disappear suddenly and without warning.
  51. 51Critical severityFrequency: OccasionalVolvo XC40Loss of electronic brake assistance due to a software faultYes: in January 2023 Volvo recalled more than 100,000 cars built in 2023, including the XC40, because a software fault in the brake module could, in rare cases, cause the electronic brake assistance functions to be lost while driving. The brake pedal continued to work manually and the update is free.Repair: €0
  52. 52Critical severityFrequency: OccasionalVolvo XC60 IILoss of electronic brake assistance due to a software faultYes: in January 2023 Volvo recalled more than 100,000 cars built in 2023 worldwide - the XC60 among them - because a software fault in the brake module could, in rare cases, cause the electronic brake assistance functions to be lost while driving. The brake pedal continued to work manually and the update is free of charge.Repair: €0
  53. 53Critical severityFrequency: OccasionalVolvo XC70 IIIBrake servo vacuum pipe chafed by the wiper mechanism on the Volvo XC70In 2012 Volvo recalled (R/2012/104 in the United Kingdom) a batch of V60, V70, XC70 and S80 cars because the wiper mechanism could rub against the brake servo vacuum pipe. If it wears through, braking assistance falls gradually and, in the worst case, can disappear suddenly and without warning.
  54. 54Critical severityFrequency: OccasionalVolvo XC90 IILoss of electronic brake assistance due to a software faultYes: in January 2023 Volvo recalled more than 100,000 cars built in 2023 worldwide - the XC90 among them - because a software fault in the brake module could, in rare cases, cause the electronic brake assistance functions to be lost while driving. The brake pedal continued to work manually and the update is free of charge.Repair: €0
  55. 55High severityFrequency: OccasionalAudi A7 C7Oil in the brake servo from the vacuum hoses (2012 3.0 TDI)Audi recalled A7s built between March and December 2012 (3.0 TDI) because oil could reach the brake servo through the vacuum hoses, damage its diaphragm and reduce brake assistance.
  56. 56High severityFrequency: OccasionalAudi Q7 4LOil in the brake servo from the vacuum hoses (3.0 TDI)On the 2012 Q7 4L with the 3.0 TDI engine, Audi issued a recall for possible oil seepage into the brake servo, which damaged its diaphragm and reduced assistance, leaving a hard pedal.
  57. 57High severityFrequency: OccasionalCitroën C4 IRecall: brake servo faultCarWiki lists among the KBA recalls one for the brake servo, which could fail; the source gives no dates or batch.
  58. 58High severityFrequency: OccasionalFiat Doblò IIBrake servo vacuum pump that may not work properly (late 2019 Doblò)In January 2020 Fiat recalled (UK) Doblòs built between 24 October and 5 December 2019 because the brake vacuum pump might not work properly. The remedy is to replace the pump; the register consulted does not detail the specific risk or the cause.
  59. 59High severityFrequency: OccasionalHyundai i20 IIVacuum hose of the brake servo incorrectly routed on the 1.0 T-GDI (recall)In June 2026 a Safety Gate alert was issued for the i20 II with the 1.0 T-GDI engine (2015-2020): the vacuum hose may be incorrectly routed, vibrate and crack, and reduce braking effectiveness. It is a precautionary campaign, with no documented failures reported by owners.
  60. 60High severityFrequency: OccasionalHyundai Kona IBrake servo that can fail: recall for Kona built in 2018-2020A Safety Gate alert from September 2023 covers a recall of the Kona (and i40) built between December 2018 and June 2020: the brake servo can fail and require much more force on the pedal.
  61. 61High severityFrequency: OccasionalLand Rover Discovery 3Possible loss of braking assistance from oil in the brake servo or vacuum pump valveIn 2009 Land Rover recalled Discovery models built between 2003 and 2009 because oil could enter the brake servo, or the non-return valve of the vacuum pump could stick after a cold start, lengthening braking. A vacuum pipe and the valve were replaced.
  62. 62High severityFrequency: OccasionalLand Rover Range Rover IVBrake servo vacuum pipe poorly routed and liable to breakIn 2015, 1,575 British Range Rovers built from August 2012 to January 2014 were recalled for inspection because the brake servo vacuum pipe could rub against the accessory drive pulley, break and leave the car without braking assistance. The pipe was repositioned or replaced.
  63. 63High severityFrequency: OccasionalLexus UXBrake booster pump failure on the UX 250h built in May 2019In November 2019 the UK's DVSA recorded the recall of 228 Lexus UX 250h built in May 2019: an electrical connection inside the brake booster pump motor could cause it to stop working. The pump assembly was inspected and replaced if necessary.
  64. 64High severityFrequency: OccasionalMercedes-Benz CLA C117Recall for a vacuum hose on the brake servoYes: according to gebrauchtwagenberater.de, in CLAs built up to April 2013 a faulty connection on the vacuum hose could limit how the brake servo works, in both the M270 petrol and OM651 diesel engines.
  65. 65High severityFrequency: OccasionalMitsubishi LancerFaulty brake servo check valve: hard brake pedal after a long stopIn 2009 the DVSA registered a campaign (R/2009/038) for 818 British Lancers built between January 2008 and April 2009: the brake servo check valve could fail and, after the car had been standing for a while, the pedal needed to be pressed harder on the first application. On the second application the system worked normally.
  66. 66High severityFrequency: OccasionalMitsubishi Outlander IIBrake servo: the switch boot can crack and the pedal does not releaseOn certain 2010-2012 Outlander IIs the brake servo switch boot can crack and break, so that the brake pedal does not release and the car cannot move. Mitsubishi corrected it with a recall that replaces the brake servo on affected cars.
  67. 67High severityFrequency: OccasionalPorsche Macan IBrake booster damaged during assembly on the first MacansA 2014 recall covered the first Macans built (from 27 January to 10 April 2014; 196 cars in the UK) because the brake booster may have been damaged during assembly: the driver has to press the pedal harder than expected, although the brakes still work. It is checked and, if necessary, replaced.
  68. 68High severityFrequency: OccasionalSuzuki BalenoBrake servo stiffens due to vacuum pump valveYes: Suzuki recalled cars over a swollen valve in the vacuum pump that can temporarily block the brake servo's vacuum. The brakes still work, but the pedal needs much more force. It affects about 481,650 cars of several models; in the UK, 71,508 Balenos from 2016-2018.
  69. 69High severityFrequency: OccasionalToyota RAV4 VBrake servo pump fault on RAV4s built in spring 2019A 2019 recall covered RAV4s built between 26/04/2019 and 06/06/2019: the brake servo pump motor could stop working and assistance could be lost, lengthening braking. In Germany it affected more than 1,300 cars.
  70. 70High severityFrequency: OccasionalVolvo S40 IIReduced brake servo assistance because of the non-return valve in the Volvo S40's vacuum pumpOn certain cold starts the vacuum pump can give less brake assistance: the car still brakes, but you have to press the pedal harder. UK campaign R/2009/052 (S40, V50, C30, C70, S80 and V70) replaces the pump's non-return valve.
  71. 71High severityFrequency: OccasionalVolvo S80 IIVolvo S80 brake vacuum pump non-return valve: reduced assistance on some cold startsIn 2009 Volvo recalled cars of several models, including the V70 and S80 (R/2009/052 in the UK), because the assistance the vacuum pump gives the brakes could decrease on certain cold starts: the brakes still work, but you have to press the pedal harder. The remedy is to replace the non-return valve.
  72. 72High severityFrequency: OccasionalVolvo V40 IBrake servo vacuum pump failure on 1999-2000 1.9 diesel V40sVolvo recalled the 1.9 diesel S40 and V40 built in 1999 and 2000 because the brake servo vacuum pump could fail, making the pedal stiff and braking take more effort. The fix was to fit a modified pump (campaign R21125, DVSA R/2002/053).
  73. 73High severityFrequency: OccasionalVolvo V50Reduced brake servo assistance because of the non-return valve in the Volvo V50's vacuum pumpOn certain cold starts the vacuum pump can give less brake assistance: the car still brakes, but you have to press the pedal harder. UK campaign R/2009/052 (S40, V50, C30, C70, S80 and V70) replaces the pump's non-return valve.
  74. 74High severityFrequency: OccasionalVolvo V70 IIIVolvo V70 brake vacuum pump non-return valve: reduced assistance on some cold startsIn 2009 Volvo recalled cars of several models, including the V70 and S80 (R/2009/052 in the UK), because the assistance the vacuum pump gives the brakes could decrease on certain cold starts: the brakes still work, but you have to press the pedal harder. The remedy is to replace the non-return valve.
  75. 75Critical severityFrequency: RareAudi Q5 ILoss of braking assistance from oil in the brake servo of the Q5 3.0 TDIOn Q5 3.0 TDIs built from March to December 2012, oil may have entered the vacuum lines to the brake servo, damaging its diaphragm and reducing braking assistance. Precautionary campaign cited by Gebrauchtwagenberater.de.
  76. 76Critical severityFrequency: RareBMW Serie 1 F40Campaign for possible loss of brake assistance (position sensor, 2022 production)Yes: BMW recalled 1 Series F40 units built between 9 June and 2 September 2022 because an erroneous signal from the engine position sensor can cause the hydraulic brake assistance to be lost.
  77. 77Critical severityFrequency: RareBMW Serie 5 E60Soft brake pedal due to a fault in the brake servo vacuum pump or hoseBMW recalled around 5,000 5 Series E60s in March 2016 because a fault in the vacuum pump (diesel) or the brake servo vacuum hose leaves the brake pedal soft with the engine running, according to fiches-auto.fr.
  78. 78Critical severityFrequency: RareBMW Serie 6 E63/E64Brake servo oilGebrauchtwagenberater records a KBA recall for oil that can enter the brake servo of cars built from 2004 to 2010 and reduce braking assistance.
  79. 79Critical severityFrequency: RareBMW X3 F25Brake servo failure due to insufficient lubrication of the vacuum pump (production from June 2012 to August 2013)Yes: according to Gebrauchtwagenberater.de, F25s built between June 2012 and August 2013 were recalled because insufficient lubrication of the vacuum pump could leave the brake servo inoperative; the usual warning is a hard brake pedal.
  80. 80Critical severityFrequency: RareBMW X5 E70Oil in the brake servo damages the diaphragm and removes assistance (built 2006-2010)Yes: according to Gebrauchtwagenberater.de, BMW recalled X5s built from 2006 to 2010 because engine oil could enter the brake servo, damage its diaphragm and cause loss of brake assistance.
  81. 81Critical severityFrequency: RareFord C-Max ILoss of brake assistance in cold weather (November 2008 to March 2009)On cars built between November 2008 and March 2009, brake assistance may fail at low temperatures, stiffening the pedal and lengthening the braking distance.
  82. 82Critical severityFrequency: RareFord Fiesta VIII2018 recall for brake servo failure (loss of brake assistance)In March 2018 Ford recalled certain Fiesta VIII units over possible brake servo failures; the servo is the part that multiplies the force you apply to the pedal. A failure like this makes the pedal much harder and lengthens the stopping distance.
  83. 83Critical severityFrequency: RareFord Focus IILoss of brake assistance in the cold (vacuum pump, 2.0 TDCi)On 2.0 TDCi units built between August 2005 and September 2006, a non-return valve in the vacuum pump can stick at low temperatures and reduce the vacuum reaching the brake servo, stiffening the pedal and lengthening braking distances.
  84. 84Critical severityFrequency: RareKia Ceed IIIRecall for possible brake servo failure (tandem pump filter)Germany's KBA registered a recall for Kia Ceed III cars built between 2018 and 2020 over a defect in the tandem pump filter that can cause the brake servo to fail, with a loss of braking assistance and a harder pedal.
  85. 85Critical severityFrequency: RareKia XCeedRecall for a defective tandem pump filter that can affect braking distanceKia XCeed 1.6 CRDi units built between 26 October 2018 and 5 October 2020 were recalled (code 220S15) because a defective filter inside the tandem pump can cause an insufficient oil supply to it, which the source links to a risk to braking distance.
  86. 86Critical severityFrequency: RareMINI Cooper F56The brake servo can fail due to a faulty weld (2023-2024 batch)In units built between December 2023 and August 2024, the hollow shaft of the brake servo may have a weld that cannot withstand the braking pressure, which reduces braking effectiveness, lengthens the stopping distance and can leave the ABS and DSC without assistance. MINI recalled 421 vehicles worldwide (Cooper, Countryman and Aceman) in January 2025.
  87. 87Critical severityFrequency: RareMINI Countryman F60The brake servo may fail because of a defective weld (2023-2024 batch)On units built between December 2023 and August 2024, the hollow shaft of the brake servo may have a weld that cannot withstand the braking pressure, which reduces braking effectiveness, lengthens the stopping distance and can leave the ABS and DSC without assistance. MINI recalled 421 vehicles worldwide (Cooper, Countryman and Aceman) in January 2025.
  88. 88Critical severityFrequency: RarePeugeot 4007Vacuum pump and brake servo relay fault: harder brake pedalIn 2014 the DVSA recorded a campaign (R/2014/126) over a possible fault in the brake servo vacuum pump system on 8 British Peugeot 4007s built in July 2010: the pump could stop, warning lights and an audible warning would come on, and the pedal had to be pressed harder. The pump and relays are replaced and the software is updated.
  89. 89Critical severityFrequency: RareToyota Prius IVThe brake booster pump motor can stop working (2019 batch)Yes: on Prius (ZVW50/ZVW55) and Prius PHV (ZVW52) units built between 26 April and 6 June 2019, the brake booster pump motor can stop working because of a defective plastic brush holder, with possible complete loss of braking assistance. Toyota recalled these units in August 2019.
  90. 90High severityFrequency: RareCitroën C-CrosserFaulty brake servo valve: reduced braking assistanceIn 2009 the DVSA registered a campaign (R/2009/032) over incorrect operation of the C-Crosser's brake servo valve, which could reduce the effectiveness of the braking assistance. The DVSA specifies that the braking function is retained. It affected only 7 British vehicles and the valve was replaced.
  91. 91High severityFrequency: RareFiat Punto IIIBrake recall campaigns: brake servo connectors and handbrake (2013)In 2013, Fiat recalled Punto cars over the brake servo connectors (February) and over a handbrake fault on around 1,000 cars (4 December), in two independent campaigns.
  92. 92High severityFrequency: RareFord Focus IVBrake servo fault in a January 2020 batch (recall)gebrauchtwagenberater.de cites, based on the KBA, a recall for a possible brake servo fault on Focus IV built between 14 and 28 January 2020, a batch of barely two weeks.
  93. 93High severityFrequency: RareFord Mondeo IVRecall over the brake servo (valve that sticks in the cold)According to the KBA, on Mondeo IV cars built between 1 November 2008 and 12 March 2009, the non-return valve in the vacuum pump can stick at low outside temperatures, leaving the brake servo with less vacuum than it needs and reducing braking assistance.
  94. 94High severityFrequency: RareVolvo C70 IIReduced brake servo assistance in cold starts on the Volvo C70: vacuum pump non-return valveIn 2009 Volvo recalled cars of several models in the UK (R/2009/052), including the C70, because the braking assistance from the vacuum pump may be reduced in certain cold starts: the brakes work, but the pedal must be pressed harder.

Problems with the brake servo by make

Problems with the brake servo in your car

10 cars have several documented faults with the brake servo. Choose yours to see only the ones that affect them, by engine and by year.

Audi 1
BMW 3
Citroën 2
Fiat 1
Opel 1
Volvo 2

How much it costs to repair a fault with the brake servo

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 brake servo

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 brake servo?

By severity and frequency, the 1.2 PureTech (loss of braking assistance from vacuum pump damage, critical severity) and the 1.8 Hybrid (brake actuator failure (hard pedal, loss of assistance), critical severity).

Which cars have problems with the brake servo?

Among those we have analysed: Kia Sportage IV (blocked tandem pump filter and loss of brake assistance), Audi e-tron (electromechanical brake booster failure and corrosion of the brake pressure unit (ABS/ESC)), BMW X5 G05 (loss of brake assistance due to integrated braking system (IBS) fault), BMW X6 G06 (loss of brake assistance due to integrated braking system (IBS) fault), BMW X7 G07 (loss of brake assistance due to integrated braking system (IBS) fault), Fiat Doblò II (brake servo vacuum hose connector that can break (2012 Doblò)), Volvo S80 II (brake servo vacuum pipe chafed by the wiper mechanism on the Volvo S80) and Volvo V70 III (brake servo vacuum pipe chafed by the wiper mechanism on the Volvo V70). In total, 87 cars with documented faults with the brake servo.

How much does it cost to repair a fault with the brake servo?

It depends a lot on the engine or car. At a dealer, from €0 to €0, including VAT, based on the 4 faults with a documented cost. The most expensive is brake servo vacuum pump non-return valve (Ford Kuga I).

What symptoms does a fault with the brake servo cause?

The most frequently cited in the documented faults: hard brake pedal or loss of brake assistance, abs or esp warning light on, esp warning light on or flashing and electric parking brake warning.

Sources

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

  1. Ford Kuga Probleme (1. Generation 2008-2013)CarWiki.de · Other source · consulted 29 October 2026 · in German
  2. Volvo ruft Autos wegen Software-Problems zurückBerliner Zeitung (dpa) · General press · published 24 January 2023 · consulted 27 September 2026 · in German