Checking components and wiring
- Check the cable between combustion preheater module (CPM) terminal #10 and the signal terminal for the combustion fan (the black lead from the fan). Check for an open-circuit. Check for a short-circuit to ground
- Check the cable between combustion preheater module (CPM) terminal #11 and the voltage terminal for the combustion fan (the red cable from the fan). Check for an open-circuit.
NOTE:
Diagnostic trouble codes (DTC) CEM-5F3A and/or CEM-5F3F may also be stored if there is a fault in the power cable.
The combustion fan must be replaced if no faults are found in the cable.
Remedy as necessary.
Other information
- See Connecting the breakout box
- See Signal specification
- For cars manufactured up to w38 2001 inclusive, see Fuel injection nozzle / fan motor / pressure equalizer, replacing For cars manufactured from w39 2001 inclusive, see Fuel injection nozzle / fan motor / pressure equalizer, replacing .
- See Contents
- Continue
Refer to Verification
- Check the electrical terminals for the combustion fan and the combustion preheater module (CPM) connector. Check for contact resistance and oxidation
- Check the cable between combustion preheater module (CPM) terminal #10 and the signal terminal for the combustion fan (the black lead from the fan). Check for an intermittent open-circuit. Check for an intermittent short-circuit to ground
- Check the cable between combustion preheater module (CPM) terminal #11 and the voltage terminal for the combustion fan (the red cable from the fan). Check for an intermittent open-circuit.
Remedy as necessary.
Other information
- See Connecting the breakout box
- To access the combustion fan, For cars manufactured up to w38 2001 inclusive, see Fuel injection nozzle / fan motor / pressure equalizer, replacing For cars manufactured from w39 2001 inclusive, see Fuel injection nozzle / fan motor / pressure equalizer, replacing .
- See Signal specification
- See Replacing the water pump for the engine coolant heater
- See Contents
- Continue
Refer to Verification