Workshop Manuals Factory service & repair Fiat
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Fiat Croma Factory Service Manual (2005-2010)22 · Fault diagnosis
22 · Diagnostics

Instrument lights dimmer not working

Make
Fiat
Model
Croma Factory Service Manual
Year
2005–2010
Section
Instrument panel › Instrument lights dimmer not working
Fault diagnosisInstrument lights dimmer not working

INSTRUMENT LIGHTS DIMMER NOT WORKING

With the ignition ON and the side lights on, the instrument panel lights up, but when the lighting controls are operated it remains on constantly

the side lights work properly

1CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Using the Examiner check, in the Instrument Panel Node ambient, that there are no errors and that the parameters are present.Move on to Step 51. Impossible to connect with the Instrument Panel control unit1. Move on to Step 2
2. Presence of errors2. Continue following the instructions on the diagnostic instrument
2ELECTRICAL POWER SUPPLY CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the electricity supply to the Instrument Panel Node is correct.Move on to Step 3Fault in positive electrical supply and/or earthReplace defective component (in the case of a fuse, find out what caused it to blow).
3CHECK ELECTRICAL CONNECTIONSALL OKPROBLEMS ENCOUNTEREDACTION

Check the wiring between the Body Computer and the Instrument Panel. In particular, check that each individual pin is properly connected.

See E4010 INSTRUMENT PANEL

Move on to Step 4Electrical connections not operationalRenew the damaged electrical connections
4CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Use an Examiner to check the possibility of connection to the Instrument Panel NodeMove on to Step 5Impossible to connect with the Instrument Panel control unit

Replace the Instrument Panel

Op. 5560B10 CONTROL PANEL - R+R

5ACTIVE DIAGNOSIS CHECKALL OKPROBLEMS ENCOUNTEREDACTION
With the Examiner in Instrument Panel Node mode, check that the instrument panel light is correctly activated in Active Diagnosis.Move on to Step 6The panel lighting is not activated

Replace the Instrument Panel

Op. 5560B10 CONTROL PANEL - R+R

6CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Using the Examiner check, in the Body Computer ambient, that there are no errors and that the lighting parameter variesMove on to Step 71. Impossible to connect to the Body Computer control unit.1. Move on to Step 7
2. Presence of errors2. Continue following the instructions on the diagnostic instrument
3. The parameters do not change3. Move on to Step 9
7ELECTRICAL POWER SUPPLY CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the electricity supply to the Body Computer Node is correct.Move on to Step 8Fault in positive electrical supply and/or earthReplace defective component (in the case of a fuse, find out what caused it to blow)
8CONNECTIONS CHECKALL OKPROBLEMS ENCOUNTEREDACTION

Check the continuity of the wiring between the control panel and the Body Computer Node

See E4010 INSTRUMENT PANEL

Also check that the MODE +/- buttons are working properly

Move on to Step 91. Electrical connections not operational1. Renew the damaged electrical connections
2. Buttons faulty

2. Replace the control panel

Op. 7040A82 SWITCH UNIT ON LEFT SIDE OF DASHBOARD - R.R.

9CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Use an Examiner to check the possibility of connection to the Body Computer NodeMove on to Step 10Impossible to connect to the Body Computer control unit.

Replace Body Computer

Op. 5505A35 MAIN BODY COMPUTER/JUNCTION UNIT - R.R.

10CHECK ON CORRECT OPERATIONALL OKPROBLEMS ENCOUNTEREDACTION
Check that the fault is no longer presentEnd of diagnosis

Parts & tools for this job For 2005 Fiat Croma

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