Test M: Charge System Indicator Never/Always On
- Check charging system operation. See GENERATORS & REGULATORS - MUSTANG article. If charging system is operating correctly, go to next step. If charging system is not operating correctly, repair as necessary.
- Turn ignition switch to RUN position. If charging indicator is not illuminated, go to next step. If charging indicator is illuminated, go to step 5 .
- Turn ignition switch to OFF position. Disconnect generator harness connector C154. Using a fused jumper wire, ground Light Green/Red wire terminal at generator harness connector C154. Turn ignition switch to RUN position. If charging indicator is not illuminated, go to next step. If charging indicator is illuminated, repair or replace generator as necessary.
- Turn ignition switch to OFF position. Disconnect instrument cluster harness connector C250. Measure resistance in Light Green/Red wire between generator harness connector C154 and terminal No. 5 at instrument cluster harness connector C250. See Figure . If resistance is 5 ohms or less, replace bulb or instrument cluster as necessary. If resistance is greater than 5 ohms, repair open in Light Green/Red wire.
- Turn ignition switch to OFF position. Disconnect generator harness connector C154. Turn ignition switch to RUN position. If charging indicator is illuminated, go to next step. If charging indicator is not illuminated, repair or replace generator as necessary.
- Turn ignition switch to OFF position. Disconnect instrument cluster harness connector C250. Measure resistance between ground and Light Green/Red wire terminal at generator harness connector C154. If resistance is greater than 10 k/ohms, replace instrument cluster. If resistance is 10 k/ohms or less, repair short to ground in Light Green/Red wire.