Pinpoint Test F: The AUTOLAMPS Are Inoperative
WARNING: This page is about a different car, the 2007 Lincoln Mark LT and 2007 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.
CAUTION:
Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
- F1 RETRIEVE THE VSM DTCs NOTE: Make sure the headlamp switch is in the OFF position.
- Key in ON position.
- Carry out the VSM on-demand self-test.
- Is DTC B1793 present?
- F2 VERIFY DTC B1793
- Key in OFF position.
- Disconnect: VSM C3008b
- Measure the resistance between the VSM C3008b-10, circuit 218 (WH/VT), harness side and ground.
- Is the resistance less than 5 ohms?
Fig 1: Measuring Resistance Between Vehicle Security Module C3008b-10, Circuit 218 (WH/VT), Harness Side And GroundCourtesy of FORD MOTOR CO.
- F3 CHECK CIRCUIT 218 (WH/VT) FOR A SHORT TO GROUND
- Disconnect: Light Sensor C286
- Measure the resistance between the VSM C3008b-10, circuit 218 (WH/VT), harness side and ground.
- Is the resistance greater than 10,000 ohms?
- YES : REPAIR the circuit. TEST the system for normal operation.
- NO : INSTALL a new light sensor. REFER to Light Sensor in this article. TEST the system for normal operation.
- F4 CHECK THE INPUT FROM THE HEADLAMP SWITCH
- Key in OFF position.
- Disconnect: VSM C3008b
- Place the headlamp switch in the AUTO position.
- Measure the voltage between the VSM C3008b-7, circuit 220 (VT/OG), harness side and ground.
- Is the voltage greater than 10 volts?
- F5 CHECK CIRCUIT 220 (VT/OG) FOR AN OPEN
- Disconnect: Headlamp Switch C2150a
- Carry out the headlamp switch component test. Refer to COMPONENT TESTING.
- Is the headlamp switch OK?
- YES : REPAIR the circuit. TEST the system for normal operation.
- NO : INSTALL a new headlamp switch. REFER to Headlamp Switch in this article. TEST the system for normal operation.
- F6 MONITOR THE VSM OUTPUT WITH THE LIGHT SENSOR DISCONNECTED
- Connect: VSM C3008b
- Disconnect: Light Sensor C286
- Key in ON position.
- Wait 10 seconds and observe the exterior lamps.
- Are the exterior lamps illuminated?
- F7 CHECK FOR VOLTAGE TO THE LIGHT SENSOR
- Measure the voltage between the light sensor C286-2, circuit 218 (WH/VT), harness side and ground.
- Is the voltage approximately 5 volts?
- YES : INSTALL a new light sensor. REFER to Light Sensor in this article. TEST the system for normal operation.
- NO : Go to F8.
- F8 CHECK FOR CORRECT VSM OPERATION
- Disconnect all the VSM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the VSM 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 VSM. REFER to MULTIFUNCTION ELECTRONIC MODULES article. 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. REPEAT the self-test.