Diagnostic Aids
WARNING: This page is about a different variant/trim than selected.
- A TRUE B+ has enough current to light a test light.
- A DIAGNOSTIC B+ is a low current circuit that DOES NOT have enough current to light a test light.
- A short to ground on the AWD indicator control circuit will cause the AWD indicator to remain ON at all times.
- An open or high resistance on the AWD indicator control circuit will cause the AWD indicator to be inoperative during the 2 second bulb inspection.
- An open in the indicator dimming control circuit will cause the 2 High, AWD, 4 High and 4 Low mode indicators to be inoperative during the 2 second bulb inspection.
- The EL-49741 harness is a good source for 9 V.
- The EL-49742 harness is a good source for B+ and ground.
- With key REMOVED - opening a door puts a true B+ on the indicator dimming control circuit, TCSCS X1 pin 4. Other possible voltages are listed below:
- Door open, key removed - indicator dimming control circuit voltage = true B+.
- Door open, key in, key OFF - indicator dimming control circuit voltage = true B+.
- Door open, key ON, engine OFF - indicator dimming control circuit voltage = diagnostic B+.
- All doors closed, key OFF - indicator dimming control circuit voltage = B+ (high current - enough to light a test light).
- All doors closed, key ON, engine OFF - indicator dimming control circuit voltage = diagnostic B+.
- Key ON, engine OFF. Place a shop light on the DRL sensor. When the DRL sensor commands the headlights OFF, the indicator dimming control circuit voltage, TCSCS X1 pin 4, will go from a diagnostic B+ to a true B+.