Powertrain
generic / SAE
P23D3
Cylinder 1 Fuel Heater Control Circuit Low
Same as P23D1 with the control line shorted to ground. The sensor heater warms the element to operating temperature (~600 °C); without it the lambda sensor stays inactive in closed loop and the ECM cannot trim mixture.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number3 / D3
Possible causes
- Control line shorted to ground high
- Connector pins corroded - high contact resistance low
- Harness chafing through insulation low
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 80–350 €
- Estimated time: 0.5–1.8 h
- Component: fuel heater cyl 1
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012