125000480 - C17 THE VEHICLE JERKS

It shudders when setting off from a standstill It shudders during a gear change Preliminary check: If the vehicle has faults in other systems (warning lights in instrument panel relating to: engine management, ABS, VDC) check the causes of these problems. If this is not the case, proceed with the following chart
Results of the tests
0OIL LEVEL CHECKAll OKProblems metOperation
Check the oil level as described in See Test    See Test 2127B OIL LEVEL CHECKContinue to Step 2Level below the Max referenceTop up the oil levelContinue to Step 1
Level above the Max referenceReduce to the Max levelContinue to Step 2
1CHECK FOR OIL LEAKSAll OKProblems metOperation
Check that there are no oil leaks as described in See Test    See Test 2127C HYDRAULIC GEAR SELECTION SYSTEMContinue to Step 2OIl leaks detectedReplace/repair the parts concerned, and top up the oil levelContinue to Step 1
2OIL PRESSURE CHECKAll OKProblems metOperation
Check the oil pressure as described in See Test    See Test 2127D OIL PRESSURE CHECKContinue to Step 4Pressure < 40 barContinue to Step 3
3ELECTRIC PUMP OPERATION CHECKAll OKProblems metOperation
Check the correct operation of the pump as described in See Test    See Test 2127E ELECTRIC SPEED SELECTION SYSTEMContinue 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 4
4CONTROL UNIT ERRORS CHECKAll OKProblems metOperation

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

  • Clutch position sensor
  • CAN message errors (reception/transmission)
Continue to Step 6Presence of one or more of the errors included in the listContinue to Step 5
5CHECKS ON FAULTS DETECTEDAll OKProblems metOperation
Check the faults in accordance with See Test    See Test 2127I What to do for error in Selespeed control unitContinue to Step 6Faulty connectionsRepair/replace the wiringContinue to Step 6
One of the control units does not dialogue (Errors on CAN network)Repair/replace the control unit concernedContinue to Step 6
6POTENTIOMETER REPLACEMENTAll OKProblems metOperation
If there is a clutch sensor error and no faults are detected in the connections/wiring, replace the clutch potentiometer Op. 2127E44and check that the position reading is correct by carrying out a series of C.M.Continue to Step 7.
7AFTER THE CHECKS ON THE FAULTS DETECTEDAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisThe fault persistsContinue to Step 8
8BLEED THE SYSTEM USING THE EXAMINERAll OKProblems metOperation
In active diagnosis carry out two system bleeding cycles using the ''clutch bleed'' commandContinue to Step 9.
9CARRY 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''Continue to Step 10.
10ROAD TESTAll OKProblems metOperation
Carry out a road test to check that the fault is no longer presentEnd of diagnosisThe fault persistsContinue to Step 11
11FURTHER CHECKS ON OTHER SYSTEMSAll OKProblems metOperation
Check that the problem has not been caused by other systems such as the engine, fuel systemContinue to Step 12There are faults on other vehicle systemsContinue in accordance with the appropriate diagnostic table
12THE FAULT PERSISTSAll OKProblems metOperation
Contact Technical Service for further information on the problemEnd of diagnosis.