Tuesday 17 October 2017

P2A04

P2A04
P2A04
Diagnosis information - DME V8 DFI
Fuel trim deviation downstream of catalytic converter, bank X
NOTE:
This fault is detected if the oxygen sensor signal behind the catalytic converter deviates so quickly and greatly (rich or lean) that the lambda control
cannot balance the mixture. (e.g. hose on intake pipe has fallen off ...)
At this moment, it is not yet clear what has caused this deviation (mixture fault, electrical fault).
A further diagnosis procedure is initiated which actively checks the sensors ahead of and behind the catalytic converter by specific enrichment and
enleanment of the mixture.
The vehicle must be driven in the same driving cycle (without ignition reset) for this purpose.
Diagnostic conditions
- Engine running > 90 seconds
- All 4 oxygen sensors ready for operation
- No inertia fuel shutoff
Possible fault causes
- Fault in fuel/air mixture
- Fault in exhaust pipe
- Fault in exhaust measurement
- Other faults are stored in the fault memory