Emissions control: EGR, DPF, catalytic converter and AdBlueGeneric OBD-II codeUrgency: Garage soon
Code P0544: exhaust temperature sensor B1S1: fault
What code P0544 means
The ECU has detected a problem in the exhaust gas temperature (EGT) sensor circuit for bank 1, sensor 1, the first probe in the exhaust pipe.[1][2]
That sensor measures the gas temperature, normally upstream of the catalytic converter or the particulate filter, and the ECU uses it to manage the mixture and the filter regeneration and to protect parts from heat.[3]
It is the general version of the circuit. Codes P0545 (low signal) and P0546 (high signal) are the same sensor with a specific direction.[2]
Note: CarWiki.de titles this code as an EGR sensor, but its own text describes it as an exhaust temperature sensor. We go with the exhaust definition.[1]
Original definition (SAE J2012): Exhaust Gas Temperature Sensor Circuit, Bank 1 Sensor 1[1][2]
Causes of P0544
From most to least likely, according to the sources.
Symptoms
- Engine warning light on.[1][3]Engine warning light: faults that cause it
- Particulate filter warning light, with shorter regenerations.[3]DPF warning light: faults that cause it
- Loss of power and poorer response.[1][3]Less power: faults that cause it
- Increased fuel consumption.[1][3]Uses more fuel: faults that cause it
How to diagnose P0544
In order: from the most likely and cheapest to check to the most expensive.
- 1Read the codes with the diagnostic tool; they show which sensor is failing.[3]
- 2Look at the live value: an impossible one, such as minus 40 degrees, indicates a broken wire or a failed sensor.[3]
- 3Visually inspect the wiring, connector and sensor, and consult the wiring diagram for the measurements.[1][3]
- 4Check the exhaust for leaks and, on diesels, the condition of the particulate filter.[1]
- 5Replace the sensor if the wire or the housing is damaged, observing the manufacturer's tightening torque (HELLA gives 40 to 45 Nm).[3]
Can I keep driving with P0544?
Garage soon
The sources set no urgency: without a reliable sensor the filter management and thermal protection can fail and emissions can rise, so get it checked soon. CarWiki's information is general and indicative.[1][3]
Documented faults related to P0544
Known faults of specific engines and cars, with their repair cost, the affected years and their sources.
Particulate filter (DPF/FAP): the most serious faults by engine and car
- High severityFrequency: Very frequentOM651EGR and particulate filter clogging, and emissions software updatesThe particulate filter and EGR clog up with short journeys, as on any diesel with these systems. In addition, Germany's KBA required software updates on several models with this engine between 2018 and 2021 because of a function that reduced EGR outside a temperature range.Repair (garage): €800–€2,500
- High severityFrequency: Common1.3 MultijetIncomplete particulate filter regenerations and oil dilutionIn heavy urban use, with short journeys that do not let the particulate filter regeneration finish, unburnt diesel passes into the sump and dilutes the oil; the level can rise on the dipstick and the oil loses its ability to lubricate. Repeated many times, it speeds up engine wear.
- High severityFrequency: Common2.0 HDiDPF clogging on additive-type systems (Eolys/cerine)The additive-type diesel particulate filter (DPF) of the 2.0 HDi clogs relatively easily on short journeys, especially on the 107/110 and 136-140 hp versions. The anti-pollution warning light comes on and, if ignored, the car loses power and may end up needing a new DPF.
- High severityFrequency: Common1.6 and 2.0 MultiJet IISaturated diesel particulate filter (DPF) from incomplete regenerationsIn urban use with short journeys, the particulate filter does not manage to complete its regeneration and becomes saturated; garages recommend a weekly motorway run to avoid it. The filter itself is among the weak points flagged in the 1.6 and 2.0 MultiJet II after a certain mileage.
Engine sensors: the most serious faults by engine and car
- High severityFrequency: Occasional2.0 DTI and 2.2 DTIVP44 injection pump and air mass meter failureGerman Wikipedia documents recurring failures of the Bosch VP44 injection pump and the air mass meter in the early years of this engine. An owner testimony for this engine describes the pump being replaced at 192,500 km, at a cost the owner calls «prohibitive».
- Medium severityFrequency: Common2.0 TDIClogged particulate filter or faulty pressure sensorThe 2.0 TDI's particulate filter clogs if the car mostly makes short journeys, because it never gets to regenerate; sometimes the fault is just the differential pressure sensor. Cleaning it costs around €200 and replacing it, €800 to €3,000.Repair (garage): €800–€3,000
- Medium severityFrequency: Common1.4 and 1.6 8vCrankshaft position sensor failure (TDC sensor)The crankshaft position sensor (capteur PMH, or TDC sensor) appears repeatedly in the reliability sources for the Clio II, the Kangoo I and the Dacia Logan I with this engine, with hard cold starting or stalling as the main symptoms. It is a cheap part, but the failure can leave you stranded.
- Medium severityFrequency: Common1.4 and 1.6 16vCrankshaft position sensor failureThe crankshaft position sensor (capteur PMH) appears repeatedly in the reliability sources for almost every generation with this engine, with hard cold starting, stalling or the car cutting out unexpectedly. It is a cheap part, but the failure can leave you stranded.
Wiring, connectors and short circuits: the most serious faults by engine and car
- Critical severityFrequency: 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.
- High severityFrequency: 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.
- High severityFrequency: 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.
- High severityFrequency: 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.
- Critical severityFrequency: CommonRover 75Seat SRS connector fault with airbag and seatbelt warning light onAuto Express warns that the Rover 75's seat SRS connector can cause the airbags to fail, and dealers were fixing it with revised connectors. The Dutch APK inspection puts the airbag or seatbelt fault warning among the most frequent defects across almost all series.
- Critical severityFrequency: 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.
Frequently asked questions
Can I drive with code P0544?
With care and to get to a garage. The sources do not give a ban, but a failed exhaust temperature sensor can upset the filter regeneration and increase emissions and consumption.[1][3]
What is the difference from P0545 and P0546?
P0545 is the same sensor with a low signal and P0546 with a high signal; P0544 is the general circuit fault.[2]
Which sensor is bank 1 sensor 1?
The first exhaust temperature sensor on bank 1, the one closest to the engine.[1][2]
Will I pass the MOT with code P0544?
If the code has switched on the engine warning light, no: with that light on, the inspection records a serious defect, and on Euro 5 and Euro 6 cars the ITV (Spain's roadworthiness inspection, similar to the MOT) also reads the OBD diagnostic system. Repair the fault before you go; clearing the code just before the inspection does not help either, because it counts as a serious defect.[4]
Not sure what is wrong with your car? Describe what you notice in the symptom diagnosis or see all fault codes.
Sources
Every fact on this page links to its source. If you find an error, let us know.
- OBD Fehlercode P0544CarWiki.de · Technical documentation · consulted 29 October 2026 · in German
- P0544 – AutoDTCsAutoDTCs · Technical documentation · consulted 29 October 2026
- Checking the exhaust gas temperature sensorHELLA Tech World · Technical documentation · consulted 29 October 2026
- Desmontando mitos: ¿puede pasar mi coche la ITV con el testigo de «avería motor» encendido?Diariomotor · Motoring press · published 8 March 2021 · consulted 2 October 2026 · in Spanish