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Trailer Lighting Module: Service and Repair



86.55.07 Electronic Control Unit (ECU) - Trailer

If the ECU is to be replaced then Testbook/T4 must be connected and correct procedures adhered to, prior to battery disconnection.

Before disconnecting the battery, ensure all text and cautions in the battery disconnection section are observed.

Remove
1. Disconnect battery earth lead.
2. Remove access panel from load space RH trim casing.





3. Remove 2 nuts securing trailer ECU.
4. Release and disconnect multiplug.
5. Remove trailer ECU.

Refit
1. Position trailer ECU and connect multiplug.
2. Fit trailer ECU and secure with nuts.
3. Fit access panel.
4. Connect the battery earth lead.
5. Configure new ECU using TestBook/T4.