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Lancia Thesis Factory Service Manual (2002-2009)22 · Fault diagnosis
22 · Diagnostics

Reversing lights not working

Make
Lancia
Model
Thesis Factory Service Manual
Year
2002–2009
Section
Lights › Reversing lights not working
Fault diagnosisReversing lights not working

REVERSING LIGHTS NOT WORKING

2.0 TB, 2.4 20V, 3.0 V6, 2.4 JTD 10V

When reverse gear is engaged the reversing warning lights do not work;

The reversing lights are controlled directly by the switch on the gearbox.

The Body Computer Node receives a lights on signal from the positive supply for the reversing light bulbs.

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:

  • the plausibility of the reversing lights On/Off parameter
Move on to StepThe parameter does not change statusMove on to Step
2DASHBOARD JUNCTION UNIT CHECKALL OKPROBLEMS ENCOUNTEREDACTION
2.4 20 V,2.0 TB,2.4 JTD 10V

Check:

  • for the presence of an input positive from the switch on the gearbox with reverse gear engaged
  • the continuity inside the dashboard junction unit to the input from the switch on the gearbox and to the output towards the bulbs

    (Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to Step1. No positive at the inputMove on to Step
2. Dashboard control unit interrupted internally

2. Replace the dashboard junction unit

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

2DASHBOARD JUNCTION UNIT CHECKALL OKPROBLEMS ENCOUNTEREDACTION

Check:

  • for the presence of an input positive from the switch on the gearbox with reverse gear engaged
  • the continuity inside the dashboard junction unit to the input from the switch on the gearbox

    (Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to Step1. No positive at the inputMove on to Step
2. Dashboard control unit interrupted internally

2. Replace the dashboard junction unit

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

3ENGINE COMPARTMENT JUNCTION UNIT CHECKALL OKPROBLEMS ENCOUNTEREDACTION
2.4 20 V,2.0 TB,2.4 JTD 10V

Check:

  • the presence of an output positive towards the switch on the gearbox
  • the continuity inside the engine compartment junction unit.

    (Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to Step1. No positive at the output.Move on to Step
2. Engine compartment junction unit interrupted inside

2. Replace engine compartment junction unit

See in Op. 5505A13 Additional junction unit in engine compartment - R.R.

4ELECTRICAL SYSTEM CHECKALL OKPROBLEMS ENCOUNTEREDACTION
2.4 20 V,2.0 TB,2.4 JTD 10V

Check the continuity between:

  • engine compartment junction unit and switch on gearbox.
  • dashboard junction unit and switch on gearbox.

    (Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to Stepwiring broken

Restore the electrical connection

(Wiring Diagram ) E2022 REVERSING LIGHTS

4ELECTRICAL SYSTEM CHECKALL OKPROBLEMS ENCOUNTEREDACTION
3.0 V6

Check the continuity between:

  • dashboard junction unit and switch on gearbox.

    (Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to Stepwiring broken

Restore the electrical connection

(Wiring Diagram ) E2022 REVERSING LIGHTS

5SWITCH ON GEARBOX CHECKALL OKPROBLEMS ENCOUNTEREDACTION
2.4 20 V,2.0 TB,2.4 JTD 10V

Check the operation of the switch on the gearbox

(Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to StepSwitch on gearbox faulty.

Replace the switch

See in Op. 5550D22 reversing light switch - r+r

5MULTIFUNCTION SWITCH ON GEARBOX CHECKALL OKPROBLEMS ENCOUNTEREDACTION
3.0 V6

Check the operation of the switch on the gearbox

(Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to StepSwitch on gearbox faulty.

Replace the switch

See in Op. 5550D22 reversing light switch - r+r

6ELECTRICAL SYSTEM CHECKALL OKPROBLEMS ENCOUNTEREDACTION

Check the continuity between the engine compartment junction unit and the dashboard junction unit.

(Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to Stepwiring broken

Restore the electrical connection

(Wiring Diagram ) E2022 REVERSING LIGHTS

7DASHBOARD JUNCTION UNIT CHECKALL OKPROBLEMS ENCOUNTEREDACTION

Check the internal continuity of the dashboard junction unit from the input connector to the fuse

(Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to Stepdashboard control unit interrupted internally

Replace the dashboard junction unit

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

8BULB CONDITION CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the condition of the reversing light bulbsMove on to StepBulbs burnt out

Replace the reversing light bulbs

See in Op. 5550D26 Reversing light BULB - R.R.

9ELECTRICAL SYSTEM CHECKALL OKPROBLEMS ENCOUNTEREDACTION

Check:

  • the continuity/insulation between the dashboard junction unit connector and the bulb connectors
  • the continuity/insulation between the bulbs and the intermediate connection.
  • the continuity/insulation between the intermediate connection and the dashboard junction unit.
  • the continuity/insulation between the bulbs and the earth

    (Wiring Diagram ) E2022 REVERSING LIGHTS

Move on to Stepwiring faulty

Restore the electrical connection

(Wiring Diagram ) E2022 REVERSING LIGHTS

10CHECK ON CORRECT OPERATIONALL OKPROBLEMS ENCOUNTEREDACTION
Check that the fault is no longer present.

Parts & tools for this job For 2002 Lancia Thesis

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