Pinpoint Test G: The AUTOLAMPS Are Inoperative
WARNING: This page is about a different car, the 2005 Mercury Mountaineer and 2005 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
- G1 RETRIEVE THE VEHICLE SECURITY MODULE DIAGNOSTIC TROUBLE CODES (DTCs) NOTE: Make sure the headlamp switch is in the OFF position.
- Key in ON position.
- Carry out the vehicle security module on-demand self-test.
- Is DTC B1792 or B1793 present?
- Yes : GO to G4.
- No : GO to G2.
- G2 CHECK THE INPUT FROM THE HEADLAMP SWITCH
- Key in OFF position.
- Disconnect: Vehicle Security Module C3203e.
- Turn the headlamp switch to the AUTO position.
- Measure the voltage between the vehicle security module C3203e-5, circuit 1399 (DB/WH), harness side and ground.
- Is the voltage greater than 10 volts?
- Yes : TURN the headlamp switch OFF. GO to G4.
- No : TURN the headlamp switch OFF. GO to G3.
- G3 CHECK CIRCUIT 1399 (DB/WH) FOR AN OPEN
- Disconnect: Headlamp Switch C205a.
- Carry out the headlamp switch component test. Refer to COMPONENT TESTING article.
- Is the headlamp switch OK?
- Yes : REPAIR circuit 1399 (DB/WH). TEST the system for normal operation.
- No : INSTALL a new headlamp switch. REFER to HEADLAMP SWITCH . TEST the system for normal operation.
- G4 MONITOR THE LIGHT SENSOR INPUT
- Connect: Vehicle Security Module C3203e.
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Vehicle Security Module Light Sensor PID.
- Turn the headlamp switch to the AUTO position.
- Monitor the vehicle security module light sensor PID while illuminating, then removing the light source from the light sensor.
- Does the PID percentage change with the sensor covered and then illuminated?
- Yes : GO to G8.
- No : GO to G5.
- G5 CHECK CIRCUIT 1205 (BK) FOR AN OPEN
- Key in OFF position.
- Disconnect: Light Sensor C286.
- Measure the resistance between the light sensor C286-5, circuit 1205 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
- Yes : GO to G6.
- No : REPAIR the circuit. TEST the system for normal operation.
- G6 CHECK CIRCUIT 218 (WH/VT) FOR SHORT TO POWER
- Disconnect: Vehicle Security Module C3203e.
- Key in ON position.
- Measure the voltage between the light sensor C286-2, circuit 218 (WH/VT), harness side and ground.
- Is any voltage present?
- Yes : REPAIR the circuit. TEST the system for normal operation.
- No : GO to G7.
- G7 CHECK CIRCUIT 218 (WH/VT) FOR OPEN OR SHORT TO GROUND
- Key in OFF position.
- Measure the resistance between the light sensor C286-2, circuit 218 (WH/VT), harness side and the vehicle security module C3203e-4, circuit 218 (WH/VT), harness side; and between the light sensor C286-2, circuit 218 (WH/VT), harness side and ground.
- Is the resistance less than 5 ohms between the light sensor and the vehicle security module; and greater than 10,000 ohms between the light sensor and ground?
- Yes : INSTALL a new light sensor. REFER to LIGHT SENSOR . TEST the system for normal operation.
- No : REPAIR the circuit. TEST the system for normal operation.
- G8 CHECK FOR VEHICLE SECURITY MODULE OPERATION
- Disconnect all the vehicle security module connectors.
- Check for:
- corrosion
- pushed-out pins
- Connect all the vehicle security module 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 vehicle security module. REFER to VEHICLE SECURITY MODULE . 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.