| STEP | CHECK TO BE PERFORMED | RESOLUTION IF THE CHECK IS NOT OK | 
|---|
| 1 | Turn on the diagnostic tester and go to Instruments.In Voltmeter mode, select a full scale deflection value 20 V and a time base of 2 s.Connect the voltmeter red probe to Pin 10 of the master headlamp 14-way connector    See F010  LEFT HEADLAMP  and the black probe to Earth.Turn one wheel by hand and when the speed is 4-6 km/h press the START button.Check that the signal acquired looks the attached graph without any dips.The test can be considered over | Move on to Step 2 | 
| 2 | Check for wiring continuity between Pin 28 of Body Computer connector B    See M001  BODY COMPUTER  , and Pin 10 of the Master headlamp 14-way connector    See F010  LEFT HEADLAMP | The test can be considered over | 
| 3 | Check for wheel speed signal errors in the ABS control unit | Continue as instructed by the diagnostic equipment | 
| 4 | Check for wiring continuity between the ABS control unit and the Body Computer    See E7020  ABS | Replace Body Computer    Op. 5505A32  BODY COMPUTER - R.R | 
| 5 | Check that the fault is no longer present | Replace the Master headlamp    Op. 5540B81 LEFT GAS DISCHARGE LIGHT CLUSTER - R.R. |