3360195 - C21 THE GEARBOX IS STUCK'

It remains stuck in one gear and, when the vehicle stops, the engine cuts out and cannot be started up again or it starts again after a few minutes.Preliminary check: If during engine starting you notice that the starter motor works normally, the problem is caused by other systems (engine management, ABS, fuel pump, etc.). Refer to specific charts.If the starter motor does not turn (after checking its operation and the relevant electrical supply circuit), continue with the next diagnosis chart.
Results of the tests
0OIL LEVEL CHECKAll OKProblems metOperation
Check the oil level See Test   2127B  OIL LEVEL CHECK Continue to Step 2Level below the Max referenceTop up the oil levelContinue to Step 1
Level above the Max referenceReduce to Max levelContinue to Step 2
1CHECK FOR OIL LEAKSAll OKProblems metOperation
Check that there are no oil leaks See Test   2127C  CHECK FOR FLUID LEAKS Continue to Step 2Oil leaks detectedReplace/repair the relevant parts, top up the oil levelContinue to Step 1
2OIL PRESSURE CHECKAll OKProblems metOperation
Check the oil pressure See Test   2127D  OIL PRESSURE CHECK Continue to Step 4Pressure < 40 barContinue to Step 3
3CHECK THE PUMP OPERATIONAll OKProblems metOperation
Check that the pump is working properly See Test   2127E  ELECTRIC PUMP OPERATION CHECK Continue to Step 4Voltage below 11 VCheck the batteryContinue to Step 3
It is not possible to make gear changes from the leverActivate the 'clutch bleed' service from the Examiner Plus or Smart to activate the pumpContinue to Step 3
4CONTROL UNIT ERRORS CHECKAll OKProblems metOperation

Check that there are no control unit errors. In particular:

  • Clutch sensor error
  • Clutch solenoid valve current error
  • Pump relay error
  • Load relay error
  • Selespeed pump error
Continue to Step 3Presence of one or more of the errors included in the list Continue to Step 1
5CHECKS ON FAULTS DETECTEDAll OKProblems metOperation
Check the faults See Test   2127I  What to do depending on the error' present in the Selespeed control unit No accelerator pedal information. End of diagnosisFaulty connections (Clutch sensor, Clutch solenoid current, Pump relay error, Load relay error, Selespeed pump, and/or Engagement sensor)Repair/replace the wiringContinue to Step 6
There are no faulty connections (Clutch sensor)Replace the clutch actuator (CSC) and check its operation by carrying out a gear change.Continue to Step 6
There are no faulty connections (Clutch solenoid current)Replace the solenoid Op.   2127C56  valve and check its operation by carrying out a gear change.Continue to Step 6
Faulty pump relay and/or fuse (Selespeed pump)Replace the componentContinue to Step 6
Pump winding faults (Selespeed pump)Replace the component Op.   2127C30  Continue to Step 6
6AFTER THE CHECKS ON THE FAULTS DETECTEDAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisThe fault persistsContinue to Step 7
7CHECK CLUTCH SENSOR WIRING LAYOUTAll OKProblems metOperation
Check the state of the connections, continuity of the wiring (it is important to pay particular attention to the layout of the clutch position sensor wiring in the engine compartment: the wire must not be too taut, and it must have sufficient slack)Continue to Step 8A fault is detectedRepair/replace the part that is not workingContinue to Step 9
8CARRY OUT CLUTCH PARAMETER CALIBRATION USING THE EXAMINERAll OKProblems metOperation
In active diagnosis carry out the calibration of the clutch parameters through the 'clutch self-calibration enablement' with a positive resultContinue to Step 9The calibration is not successfulContinue to Step 10
9CHECK THAT THE FAULT IS NO LONGER PRESENTAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisThe fault persistsContinue to Step 10
10THE FAULT PERSISTSAll OKProblems metOperation
Contact Technical Service for further information on the problemEnd of diagnosisFault persistsSearch for the fault starting from another symptom'