General notes on troubleshooting

The following notes must be observed in order to find the root cause of faults when problems are reported, and to prevent the unauthorised, i.e. inappropriate, replacement of the turbocharger:

1. Tracking down and verifying the complaint 

   If possible, any problem reported ('complaint') should be tracked down and verified on the vehicle. The parameters or marginal conditions prevailing at the time the problem was reported need to be noted down.

2. Diagnosis 

   As a first procedural step, diagnosis must  be performed using the diagnosis system.

   Faults on sensors and actuators may be responsible for 'complaints', i.e. reported problems, which may also be associated with the turbocharger in some way. For this reason, faults on sensors and actuators must  first be remedied if these are stored in the fault memory.

   In addition, the engine ventilation is important for the oil supply to the turbocharger. If the pressure in the crankcase is too high, the oil supply to the turbocharger is endangered, and oil leakage may occur at the turbocharger.

   The stored charging pressure control faults must then be investigated or troubleshooting must take place on the turbocharger.

3. Repair history 

If possible, check to find out whether repairs have already been made on or near the turbocharger following similar reported problems.

• With any repeated complaint with different fault patterns, the problem could have arisen during the last repair. Problems could have arisen in conjunction with installation, connections or the ingress of foreign bodies.
• In the event of identical complaints, it is highly probable that the actual cause of the fault has not been remedied.