Lamps/Lighting - Interior (Service Information): Operation: Notes

The lamps of the interior lighting system can be divided into general classifications based upon the circuit that controls their operation: The courtesy lamp circuit, the reading lamps circuit and the panel lamps dimmer circuit. In vehicles equipped with the optional ambient lighting package, the ambient lights are actually controlled by the courtesy lamp circuit as well as by dedicated ambient lighting outputs based upon an input from the ambient lighting thumbwheel of the dimmer module. Following are paragraphs that briefly describe the operation of the courtesy lamps, reading lamps and panel lamps dimmer interior lighting circuits.

The lamps and the hard wired circuits between components related to the interior lighting system may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.

However, conventional diagnostic methods will not prove conclusive in the diagnosis of the interior lighting system or the electronic controls or communication between modules and other devices that provide some features of the interior lighting system. The most reliable, efficient, and accurate means to diagnose the interior lighting system or the electronic controls and communication related to interior lighting system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.