198001758 - I012 LEFT OR RIGHT DIRECTION INDICATORS NOT WORKING

When the lever on the steering column switch unit is raised or lowered (only one of the two cases) with the ignition ON, the direction indicators do not work.
Only carry out the checks described on the side where the problem occurs
Test results
0PRELIMINARY CHECKSAll OKProblems encounteredOperation
Press the hazard warning lights switch in the control panel and check whether the direction indicators/hazard warning lights are activated and deactivatedMove on to Step 4Lights faulty with activation of hazard warning lights as wellMove on to Step 1
1CHECK USING DIAGNOSTIC EQUIPMENTAll OKProblems encounteredOperation
Connect the Examiner equipment to the diagnostic socket.

Check:

  • that there are no faults in the body computer
  • the operation of the lights through active diagnosis.
Move on to Step 4Faults in the Body ComputerContinue as described by the diagnostic equipment
Some of the lamps do not manage to come onMove on to Step 3
None of the lamps manages to come onMove on to Step 2
2TURN SIGNAL ELECTRICAL CIRCUIT CHECKAll OKProblems encounteredOperation
Check the condition of the individual bulbs and associated bulb holder;

Check the following, in order:

Move on to Step 3Component defectiveReplace defective component (in the case of a fuse, find out what caused it to blow)
Connections interruptedRepair the connections See    See E2020 DIRECTION INDICATORS / HAZARD WARNING LIGHTS
3INDIVIDUAL BULB CHECKAll OKProblems encounteredOperation
Check the condition of the defective individual bulbs and associated bulb holderMove on to Step 4Front bulb damagedReplace the bulb    Op. 5550C54 BULB FOR ONE SIDE REPEATER UNIT LH OR RH - R.R
Rear bulb damagedReplace the bulb    Op. 5550C54 BULB FOR ONE SIDE REPEATER UNIT LH OR RH - R.R
Side repeater damagedReplace the side repeater.    Op. 5550C22 L/H OR R/H SIDE REPEATER (ONE) - R+R
Rear bulb holder assembly faultyReplace the bulb holder assembly.    Op. 5540A44 REAR LIGHT CLUSTER (ONE), LEFT OR RIGHT - R.R.
4STEERING COLUMN SWITCH UNIT CHECKAll OKProblems encounteredOperation
Check that the steering column switch unit is working properly and that the direction indicators switch is working properlyMove on to Step 5Stalk unit not working properlyReplace the steering column switch unit.    Op. 5550A10 STALK UNIT ASSEMBLY - R+R
5BODY COMPUTER POWER SUPPLY CHECKAll OKProblems encounteredOperation
Check that the power supply for the Body Computer is correctMove on to Step 6Supply not correctRestore correct power supply See    See E2020 DIRECTION INDICATORS / HAZARD WARNING LIGHTS
6CORRECT OPERATION CHECKAll OKProblems encounteredOperation
Check that the fault is no longer presentEnd of diagnosisFault persistsReplace body computer    Op. 5505A35 MAIN BODY COMPUTER/JUNCTION UNIT - R.R.