Workshop Manuals Factory service & repair Lancia
Lancia Thesis Factory Service Manual (2002-2009)22 · Fault diagnosis
22 · Diagnostics

Dipped headlamps not working

Make
Lancia
Model
Thesis Factory Service Manual
Year
2002–2009
Section
Lights › Dipped headlamps not working
Fault diagnosisDipped headlamps not working

DIPPED HEADLAMPS NOT WORKING

Both the dipped headlamps are not working in any conditions (in both manual and AUTO mode);

The dipped headlamps are controlled by the Body Computer Node via a relay located in the Dashboard Junction Unit.

The lights can be switched on/off using the following controls:

  • The dipped headlamps are controlled by the Body Computer Node via a relay located in the Dashboard Junction Unit.
  • The lights can be switched on/off using the following controls:
  • 1. Specific command (from the Exterior Lights Control)
  • 2. Command from the dusk sensor
  • 3. Follow me home command
  • 4. "Dipped headlamp maintenance" command when the main beam headlamps are switched on.
STEPOPERATIONS TO BE CARRIED OUTTEST RESULTS
1CHECK USING DIAGNOSTIC EQUIPMENT.ALL OKPROBLEMS ENCOUNTEREDACTION

Connect the Examiner diagnostic equipment to the diagnostic socket and check the following at the Body Computer Node:

  • that there are no faults in the Dipped Headlamps Relay
Move on to StepPresence of dipped headlamps relay fault.Continue following the instructions for the diagnostic equipment
2CHECK USING DIAGNOSTIC EQUIPMENT.ALL OKPROBLEMS ENCOUNTEREDACTION

Keeping the diagnostic equipment connected, check the following at the Body Computer Node:

  • the operation of the relay through active diagnosis
Move on to StepThe relay is not activated.Move on to Step
3MAIN BEAM HEADLAMPS RELAY CHECK.ALL OKPROBLEMS ENCOUNTEREDACTION
Check the condition of the main beam headlamps relayMove on to StepRelay defective.Replace the relay
4CHECK ON ELECTRICAL SYSTEM INSIDE DASHBOARD JUNCTION UNIT (control circuit)ALL OKPROBLEMS ENCOUNTEREDACTION

Check the continuity of the connections for the interior lights control circuit to the dashboard junction unit

(Wiring Diagram ) E2011 DIPPED BEAMS

Move on to StepOpen circuit for connection in dashboard junction unit

Replace Dashboard Junction Unit

See in Op. 5505A10 Junction UNIT - R.R.

5CHECK ON ELECTRICAL SYSTEM INSIDE DASHBOARD JUNCTION UNIT (power circuit)ALL OKPROBLEMS ENCOUNTEREDACTION

Check the continuity of the connections for the dipped headlamps power circuit to the dashboard junction unit

(Wiring Diagram ) E2011 DIPPED BEAMS

Move on to StepOpen circuit for connection in dashboard junction unit

Replace Dashboard Junction Unit

See in Op. 5505A10 Junction UNIT - R.R.

6CHECK ON CORRECT OPERATIONALL OKPROBLEMS ENCOUNTEREDACTION
Check that the fault is no longer presentFault persists.

Replace body computer

See in Op. 5505A32 BODY COMPUTER - R.R.

Parts & tools for this job For 2002 Lancia Thesis

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