Diagnosis And Testing - Dimmer Switch
WARNING:
To avoid serious or fatal injury on vehicles equipped with airbags, disable the Supplemental Restraint System (SRS) before attempting any steering wheel, steering column, airbag, seat belt tensioner, impact sensor or instrument panel component diagnosis or service. Refer to WARNING . Disconnect and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge before performing further diagnosis or service. This is the only sure way to disable the SRS. Failure to take the proper precautions could result in accidental airbag deployment.
- Remove the dimmer module from the instrument panel. Refer to SWITCH, DIMMER, REMOVAL .
- Disconnect the instrument panel wire harness connector from the back of the dimmer module.
- Using an ohmmeter, test the resistance between the terminals of the module as shown in the Dimmer Module Tests table.
DIMMER MODULE TESTS SWITCH POSITION (PINS) RESISTANCE RANGE (OHMS) DOME DEFEAT (1 and 4) 8645 - 9555 PANEL DIMMER 1 (1 and 4) 2565 - 2835 PANEL DIMMER 2 (1 and 4) 1140 - 1260 PANEL DIMMER 3 (1 and 4) 646 - 714 PANEL DIMMER 4 (1 and 4) 417.78 - 426.22 PANEL DIMMER 5 (1 and 4) 256.5 - 283.5 PANEL DIMMER 6 (1 and 4) 180.18 - 183.82 PARADE MODE (1 and 4) 135.63 - 138.37 DOME ON (1 and 4) 172.26 - 175.74 SWITCH ILLUMINATION (2 and 3) LEDs - SET MULTIMETER TO DIODE MODE - CONNECT PIN 3 TO PLUS (+), CONNECT PIN 2 TO MINUS (-) - LEDs SHOULD BARELY GLOW - If the module fails any of the tests, replace the ineffective dimmer module as required.