IFI Diagnosis/Fault Memory

Notes re fault memory
- Fault memory: fault display
current faults: have a grey background grid
stored faults: are highlighted

All inputs/outputs are checked for plausibility when driving. All faults which exist are stored in the fault memory of the IFI control module (N3/7).
The faults remain stored with ignition "OFF" or after disconnecting the car battery.
The EDC (Electronic Diesel Control) malfunction indicator lamp (A1e34) comes on if major faults exist

(USA) version
The CHECK ENGINE malfunction indicator lamp (A1e26) comes on or

CHECK ENGINE
ENGINE ELECTRONICS
appears in the multifunction display if faults exist in exhaust components.
The faults are identified with the OBD fault code. Such faults are:
- lifting sensor B28/3
- EGR vacuum transducer Y31/1
- pressure-regulating flap vacuum transducer Y31/2

Fault ambient data
The fault ambient data which existed at the moment the fault was stored can be displayed additionally with the HHT. Only the ambient data which existed when the fault first occurred are stored. The ambient data are distributed over several image pages (up to 8 image pages), the last two image pages being intended solely for the Development. Image pages with the result V/F explain the causes of the fault e.g.:
- voltage too high
- voltage too low
- signal too large
- signal too small
- value implausible