22 · Diagnostics

Fog lights not working

Make: Lancia
Model: Thesis Factory Service Manual
Year: 2002–2009
Section: Lights › Fog lights not working

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Fault diagnosisFog lights not working

FOG LIGHTS NOT WORKING

The fog lights are not working;

The fog lights are controlled by the Body Computer Node via a relay located in the Engine Compartment Junction Unit.

The lights can be switched on/off by the button on the Exterior Lights Control.

STEP	OPERATIONS TO BE CARRIED OUT	TEST RESULTS
0	PRELIMINARY CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the condition of the fog lights fuse in the engine compartment junction unit	Move on to Step	Fuse blown	Replace the fuse
1	CHECK USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the Examiner diagnostic equipment to the diagnostic socket and check the following at the Body Computer Node: that there are no faults at the Fog Lights Relay the plausibility of the fog lights on/off parameter the operation of the relay through active diagnosis	Move on to Step	1. Presence of dipped headlamps relay fault	1. Continue following the instructions for the diagnostic equipment
			2. The fog lights on parameter does not change status	Move on to Step
			3. The relay is not activated	Move on to Step
2	FOG LIGHTS RELAY CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the condition of the fog lights relay	Move on to Step	Relay defective.	Replace the relay
3	CHECK ON ELECTRICAL SYSTEM INSIDE ENGINE COMPARTMENT JUNCTION UNIT (control circuit)	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the internal continuity of the engine compartment junction unit (control circuit) (Wiring Diagram ) E2030 FOG LIGHTS	Move on to Step	Open circuit for connection in engine compartment junction unit	Replace the engine compartment junction unit See in Op. 5505A13 Additional junction unit in engine compartment - R.R.
4	ELECTRICAL SYSTEM CHECK.	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the continuity of the electrical connection between the engine compartment junction unit and the Body Computer Node (Wiring Diagram ) E2030 FOG LIGHTS	Move on to Step	Connection broken	Restore the electrical connection (Wiring Diagram ) E2030 FOG LIGHTS
5	CHECK ON ELECTRICAL SYSTEM INSIDE JUNCTION UNIT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the internal continuity of the engine compartment junction unit (power circuit) (Wiring Diagram ) E2030 FOG LIGHTS	Move on to Step	Open circuit for connection in engine compartment junction unit	Replace the engine compartment junction unit See in Op. 5505A13 Additional junction unit in engine compartment - R.R.
6	ELECTRICAL SYSTEM CHECK.	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Remove the right front wheel arch liner and check the continuity of the electrical connection between the engine compartment junction unit and the front bumper connection	Move on to Step	Connection broken	Restore the electrical connection
7	ELECTRICAL SYSTEM CHECK.	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the continuity of the electrical connection between the front bumper connection and the right front earth (Wiring Diagram ) E2030 FOG LIGHTS	Move on to Step	Connection broken	Restore the electrical connection (Wiring Diagram ) E2030 FOG LIGHTS
8	ELECTRICAL SYSTEM CHECK.	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Remove the lower shield and check the continuity of the electrical connection between the front bumper connection and the fog lights (Wiring Diagram ) E2030 FOG LIGHTS	Move on to Step	Connection broken	Restore the electrical connection
9	FOG LIGHT BULBS CONDITION CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the condition of the fog light bulbs	Move on to Step	Bulbs faulty	Replace the bulbs
10	FOG LIGHTS CONTROL CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the operation of the exterior lights control button (See Test 5540AA)	Move on to Step	Fog lights control button faulty	Replace the Exterior Lights Control See in Op. 5040A20 Air conditioning COMPRESSOR - R.R. - Includes fluid level check and top up if necessary
11	ELECTRICAL SYSTEM CHECK.	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the continuity between the exterior lights control and the Body Computer Node. (Wiring Diagram ) E2030 FOG LIGHTS	Move on to Step	Connection broken	Restore the electrical connection (Wiring Diagram ) E2030 FOG LIGHTS
12	CHECK ON CORRECT OPERATION	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the fault is no longer present		Fault persists	Replace body computer See in Op. 5505A32 BODY COMPUTER - R.R.

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

Parts & tools for this job For 2002 Lancia Thesis

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