Test U: Headlight Warning Chime Inoperative
- Turn ignition switch to LOCK position. Connect New Generation Star (NGS) tester to Data Link Connector (DLC). Using NGS tester, monitor Generic Electronic Module (GEM) PID HDLMPSW while turning headlights on and off. If PID always indicates OFF, go to next step. If PID always indicates ON, go to step 5
. If PID agrees with switch position, replace GEM.
- Turn ignition switch to LOCK position. Disconnect GEM harness connector C236. Measure resistance between ground and terminal No. 15 (Orange/Red wire) at GEM harness connector C236. See Figure
. If resistance is greater than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in Orange/Red wire.
- Disconnect headlight switch harness connector C2031. Measure resistance in Orange/Red wire between terminal No. 10 at headlight switch harness connector C2031 and terminal No. 15 at GEM harness connector C236. See Figure
and Fig 1
. If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair open in Orange/Red wire.
- Connect headlight switch harness connector C2031. Turn headlight switch on. Measure voltage terminal No. 15 (Orange/Red wire) at GEM harness connector C236. If battery voltage exist, replace GEM. If battery voltage does not exist, replace headlight switch.
- Disconnect headlight switch harness connector C2031. Measure voltage at terminal No. 10 (Orange/Red wire) at headlight switch harness connector C2031. See Fig 1
. If voltage does not exist, go to next step. If voltage exists, repair short to voltage in Orange/Red wire. If voltage does not exist, go to next step.
- Disconnect GEM harness connector C236. Ensure headlight switch is off. Connect headlight switch harness connector C2031. Measure voltage terminal No. 15 (Orange/Red wire) at GEM harness connector C236. See Figure
. If voltage exist, replace headlight switch. If voltage does not exist, replace GEM.
Courtesy of FORD MOTOR CO.