22 · Diagnostics

Fog lights not working

Make: Fiat
Model: Idea Factory Service Manual
Year: 2003–2012
Section: Lights › Fog lights not working

‹ Prev Reversing lights not working Next › Rear fog lamps not working

Fault diagnosisFog lights not working

FOG LIGHTS NOT WORKING

When the front fog lamps switch is operated with the side lights on, the front fog lamps do not work.

1	CHECK ON FRONT FOG LIGHT RELAY (POWER CIRCUIT)	All OK	Problems met	Operation
		Results of the tests
	On the engine compartment control unit, swap the front fog light relay with the horn relay (it is the third on the same row), and check that the front fog light works properly after the swap.	Continue to Step 2	Even after the swap, the front fog lights still do not work	Continue to Step 3
2	REPLACING HORN RELAY (POWER CIRCUIT)	All OK	Problems met	Operation
	Replace the horn relay (which was previously the front fog light relay) and check that they are working properly	End of diagnosis
3	CHECKING FRONT FOG LIGHT RELAY SUPPLY (POWER CIRCUIT)	All OK	Problems met	Operation
	Refit the two relays in their original positions. With the ignition on, check that the front fog light is correctly supplied by the battery. Then connect to the relay supply from the Body Computer and check that when the front fog lights are switched on, the supply is sent to the relay. Also check that the electrical connections between the Body Computer, battery and relay are not faulty See E2030 FOG LIGHTS Do not connect the relay	Continue to Step 4	No supply from battery	Restore the correct supply to the relay. If necessary replace the faulty components (if a fuse is involved, search for the cause of the problem)
			Supply enablement not provided by the Body Computer	Continue to Step 6
			Connections faulty	Restore the correct connections See E2030 FOG LIGHTS
4	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Connect the Examiner to the diagnostic socket. Check that there are no faults in the Body Computer Check light operation while in active diagnosis mode.	Continue to Step 5	Fog lamp relay error	Continue to Step 6
		Continue to Step 5	Lights not activated	Continue to Step 5
5	CHECK ON INDIVIDUAL LIGHTS	All OK	Problems met	Operation
	Check the condition of individual bulbs and lamps	Continue to Step 6	Bulb damaged	Change the bulb Op. 5540B22
			Left light cluster faulty	Repair or change the light unit Op. 5540B78
			Right light cluster faulty	Repair or change the light unit Op. 5540B79
6	CHECK FOG LAMP ELECTRIC CIRCUIT	All OK	Problems met	Operation
	Check, in order: front fog lamp fuse; connections between Body Computer and engine bay control unit; connections between engine bay control unit and bulbs; connections between Body Computer and fog lights switch; bulb earth See E2030 FOG LIGHTS	Continue to Step 7	Defective component	Replace the component involved (if a fuse is involved, search for the cause of the problem)
		Continue to Step 7	Connections broken	Restore the connections See E2030 FOG LIGHTS
7	CHECK ON FRONT FOG LAMPS SWITCH	All OK	Problems met	Operation
	Check the operation of the fog lights switch See E2030 FOG LIGHTS	Continue to Step 8	Fog lights switch faulty	Replace the control panel Op. 7040A56
8	CHECK ON CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis	The fault persists	Replace the Body Computer Op. 5505A32

‹ Prev Reversing lights not working Next › Rear fog lamps not working

Parts & tools for this job For 2003 Fiat Idea

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