Pinpoint Test M: The Hazard Warning Lamps Are Inoperative/Always On
- M1 CHECK THE HAZARD LAMP SWITCH CIRCUITRY
- Key in OFF position.
- Disconnect: GEM C201d.
- Measure the resistance between the GEM C201d pin 23, circuit 91S-LG8 (BK/OG), harness side and ground while pressing and releasing the hazard lamp switch.
Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms with the switch pressed and greater than 10,000 ohms with the switch released?
- Yes
: GO to M4.
- No
: GO to M2.
- M2 CHECK THE HAZARD LAMP GROUND CIRCUIT FOR AN OPEN
- Disconnect: Hazard Switch C2039.
- Measure the resistance between the hazard switch C2039-5, circuit 91-LG8 (BK/OG), harness side and ground.
Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes
: GO to M3.
- No
: REPAIR the hazard lamp ground circuit. TEST the system for normal operation.
- M3 CHECK CIRCUIT 91S-LG8 (BK/OG) FOR AN OPEN OR A SHORT TO GROUND
- Measure the resistance between the hazard switch C2039-5, circuit 91S-LG8 (BK/OG), harness side and the GEM C201d pin 23, circuit 91S-LG8 (BK/OG), harness side; and between the hazard switch C2039-5, circuit 91S-LG8 (BK/OG), harness side and ground.
Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms between the hazard switch and the GEM; and greater than 10,000 ohms between the hazard switch and ground?
- Yes
: GO to M4.
- No
: REPAIR the circuit. TEST the system for normal operation.
- M4 CHECK FOR CORRECT GEM OPERATION
- Disconnect the GEM connectors.
- Check for:
- Corrosion
- Pushed-out pins
- Connect the GEM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes
: INSTALL a new GEM. REFER to MULTIFUNCTION ELECTRONIC MODULES
. TEST the system for normal operation.
- No
: The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. TEST the system for normal operation.