Powertrain
generic / SAE
P040C
EGR Temperature Sensor A Circuit Low
EGR temperature sensor A below lower plausibility — short to ground. EGR mixes inert exhaust into intake to lower combustion peak temperature — too little raises NOx, too much causes misfires and rough running.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number4 / 0C
Possible causes
- Short to ground high
- Connector pins corroded - high contact resistance low
- Harness chafing through insulation low
Symptoms
- Check engine light on
- Pinging or knocking under load
- Power loss and hesitation
- Possible rough idle
- Failed emissions inspection (NOx)
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 60–400 €
- Estimated time: 0.5–2 h
- Component: egr temperature sensor
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012