A-1 L-Code Diagnosis

Lighting codes (L-Codes) are set by the Body Control Module (BCM) when a fault is detected with the distributed lighting system. To effectively determine a fault in the lighting system Chart A-1 must be followed or mis-diagnosis may result.

Notes on Trouble Tree
1. If no "200 series" codes are set (L202, L203,L210) then each code should be diagnosed with the chart associated with each code set.
2. if only one "200 series" code is set and is current, then use the chart for the set 200 series code. If the codes are history, then see the note on intermittents.
3. If code L110 and all of the 200 series codes are set this indicates that the data circuit is shorted to ground or voltage. Chart A-2 should be used to diagnosis the problem.
4. 5, and 6 These combinations of codes will be set if there is a OSM power supply problem. Charts A-3, A-4, and A-5 should be used to diagnose these conditions, based on which codes are set.
7. 8, 9 and 10 These codes indicate a problem with OSM addressing. Charts B-1, B-2, B-3, and B-4 are to be used to diagnose those codes.

NOTE ON INTERMITTENTS
Reference the wiring schematic of the code that is set. Check for loose connectors and/or poor wire splices or terminals.