Pinpoint Test H: The Autolamps Are On Continuously
Autolamps
Pinpoint Tests
Pinpoint Test H: The Autolamps Are On Continuously
Refer to Wiring Diagram Set 85, Headlamps/Autolamps for schematic and connector information. Diagrams By Number
Normal Operation
The Smart Junction Box (SJB) sends a voltage signal to the headlamp switch and the light sensor.
When the headlamp switch is placed in the AUTOLAMPS ON position, the voltage signal is routed to ground. When the SJB detects the headlamp switch in the AUTOLAMPS ON position, the SJB monitors the light sensor input. The light sensor determines the amount of light based on the input received from the ambient lighting conditions. When the ambient level has reached a point (determined by the internal programming of the SJB), the SJB provides voltage to the headlamps, parking and license plate lamps.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Light sensor
- Headlamp switch
- Windshield wiper motor
- SJB
PINPOINT TEST H: THE AUTOLAMPS ARE ON CONTINUOUSLY
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
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H1 CHECK THE SJB AUTOLAMP ON REQUEST PID
NOTE: Make sure the headlamp switch is lined up in the correct position when monitoring the PID.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: SJB DataLogger.
- While placing the headlamp switch in the AUTOLAMPS ON and then OFF position, monitor the SJB headlamp switch input PID (HDLMP_AUT_CKT).
- Does the PID indicate ON with the headlamp switch in the AUTOLAMPS ON position and OFF when the headlamp switch is in the OFF position
Yes
GO to H5.
No
GO to H2.
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H2 CHECK FOR A VOLTAGE SIGNAL TO THE HEADLAMP SWITCH
- Ignition OFF.
- Disconnect: Headlamp Switch C205.
- Measure the voltage between the headlamp switch C205-9, circuit CLF19 (VT/GN), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
INSTALL a new headlamp switch. REFER to Headlamp Switch Service and Repair. CLEAR the DTCs. REPEAT the self-test.
No
GO to H3.
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H3 CHECK AUTOLAMPS REQUEST INPUT CIRCUIT FOR A SHORT TO GROUND
- Disconnect: SJB C2280b.
- Measure the resistance between the headlamp switch C205-9, circuit CLF19 (VT/GN), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to H4.
No
REPAIR circuit CLF19 (VT/GN) for a short to ground. CLEAR the DTCs. REPEAT the self-test.
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H4 CHECK THE AUTOLAMPS REQUEST INPUT CIRCUIT FOR AN OPEN
- Measure the resistance between the headlamp switch C205-9, circuit CLF19 (VT/GN), harness side and the SJB C2280b-50, circuit CLF19 (VT/GN), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to H16.
No
REPAIR circuit CLF19 (VT/GN) for an open. CLEAR the DTCs. REPEAT the self-test.
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H5 CHECK THE SJB HEADLAMP SWITCH PIDs
NOTE: Make sure the headlamp switch is lined up in the correct position when monitoring the PIDs.
NOTE: Only one PID should indicate ON at each headlamp switch position.
- Enter the following diagnostic mode on the scan tool: SJB DataLogger.
- While moving the headlamp switch through all position, monitor the SJB headlamp switch input PIDs (HDLMP_OFF_CKT, HDLMP_PRK_CKT and HDLMP_ON_CKT).
- Do the headlamp switch positions agree with the PIDs (with only one PID indicating ON in each position)?
Yes
GO to H6.
No
GO to Pinpoint Test D Pinpoint Test D: The Low Beams Are Always On.
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H6 USE THE RECORDED DTCs FROM THE SJB SELF-TEST
- Check the recorded results from the SJB self-test.
- Were any DTCs recorded?
Yes
For DTC B2008, GO to H8.
For DTC B1791, GO to H10.
For DTC B1793, GO to H14.
For all other DTCs, REFER to Diagnostic Trouble Code (DTC) Chart Testing and Inspection.
No
GO to H7.
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H7 CHECK FOR VOLTAGE TO THE LIGHT SENSOR (NO DTC)
- Ignition OFF.
- Disconnect: Light Sensor C286 or C287.
- Ignition ON.
- Place the headlamp switch in the AUTOLAMPS ON position.
- On vehicles with automatic temperature control, measure the voltage between the light sensor C287-2, circuit VLF14 (BU/BN), harness side and ground.
- On vehicles with manual climate control, measure the voltage between the light sensor C286-A, circuit VLF14 (BU/BN), harness side and ground.
- Is the voltage approximately 5 volts?
Yes
INSTALL a new light sensor. REFER to Light Sensor Service and Repair. CLEAR the DTCs. REPEAT the self-test.
No
GO to H16.
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H8 CHECK THE WINDSHIELD WIPER MOTOR
- Ignition OFF.
- Disconnect: Wiper Motor C125.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: SJB Self-Test.
- Repeat the SJB self-test.
- Is DTC B2008 still present?
Yes
GO to H9.
No
INSTALL a new windshield wiper motor. REFER to Wiper and Washer Systems. TEST the system for normal operation.
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H9 CHECK WINDSHIELD WIPERS ON INPUT CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: SJB C2280f.
- Measure the resistance between the windshield wiper motor C125-2, circuit CRW01 (WH), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to H16.
No
REPAIR circuit CRW01 (WH) for a short to ground. CLEAR the DTCs. REPEAT the self-test.
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H10 CHECK FOR VOLTAGE TO THE LIGHT SENSOR (DTC B1791)
- Ignition OFF.
- Disconnect: Light Sensor C286 or C287.
- Ignition ON.
- Place the headlamp switch in the AUTOLAMPS ON position.
- On vehicles with automatic temperature control, measure the voltage between the light sensor C287-2, circuit VLF14 (BU/BN), harness side and ground.
- On vehicles with manual climate control, measure the voltage between the light sensor C286-A, circuit VLF14 (BU/BN), harness side and ground.
- Is the voltage approximately 5 volts?
Yes
GO to H13.
No
GO to H11.
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H11 CHECK THE LIGHT SENSOR INPUT CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: SJB C2280b.
- Ignition ON.
- On vehicles with automatic temperature control, measure the voltage between the light sensor C287-2, circuit VLF14 (BU/BN), harness side and ground.
- On vehicles with manual climate control, measure the voltage between the light sensor C286-A, circuit VLF14 (BU/BN), harness side and ground.
- Is any voltage present?
Yes
REPAIR circuit VLF14 (BU/BN) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to H12.
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H12 CHECK THE LIGHT SENSOR INPUT CIRCUIT FOR AN OPEN
- Ignition OFF.
- On vehicles with automatic temperature control, measure the resistance between the light sensor C287-2, circuit VLF14 (BU/BN), harness side and the SJB C2280b-46, circuit VLF14 (BU/BN), harness side.
- On vehicles with manual climate control, measure the resistance between the light sensor C286-A, circuit VLF14 (BU/BN), harness side and the SJB C2280b-46, circuit VLF14 (BU/BN), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to H16.
No
REPAIR circuit VLF14 (BU/BN) for an open. CLEAR the DTCs. REPEAT the self-test.
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H13 CHECK FOR VOLTAGE TO THE LIGHT SENSOR USING THE CONNECTOR GROUND
- For vehicles with automatic temperature control, measure the voltage between the light sensor C287-2, circuit VLF14 (BU/BN), harness side and the light sensor C287-4, circuit GD133 (BK), harness side.
- For vehicles with manual climate control, measure the voltage between the light sensor C286-A, circuit VLF14 (BU/BN), harness side and the light sensor C286-B, circuit GD133 (BK), harness side.
- Is the voltage approximately 5 volts?
Yes
INSTALL a new light sensor. REFER to Light Sensor Service and Repair. CLEAR the DTCs. REPEAT the self-test.
No
REPAIR circuit GD133 (BK) for an open. CLEAR the DTCs. REPEAT the self-test.
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H14 CHECK FOR VOLTAGE TO THE LIGHT SENSOR (DTC B1793)
- Ignition OFF.
- Disconnect: Light Sensor C286 or C287.
- Ignition ON.
- Place the headlamp switch in the AUTOLAMPS ON position.
- On vehicles with automatic temperature control, measure the voltage between the light sensor C287-2, circuit VLF14 (BU/BN), harness side and ground.
- On vehicles with manual temperature control, measure the voltage between the light sensor C286-A, circuit VLF14 (BU/BN), harness side and ground.
- Is the voltage approximately 5 volts?
Yes
INSTALL a new light sensor. REFER to Light Sensor Service and Repair. CLEAR the DTCs. REPEAT the self-test.
No
GO to H15.
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H15 CHECK THE LIGHT SENSOR INPUT CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: SJB C2280b.
- On vehicles with automatic temperature control, measure the resistance between the light sensor C287-2, circuit VLF14 (BU/BN), harness side and ground.
- On vehicles with manual temperature control, measure the resistance between the light sensor C286-A, circuit VLF14 (BU/BN), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to H16.
No
REPAIR circuit VLF14 (BU/BN) for a short to ground. CLEAR the DTCs. REPEAT the self-test.
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H16 CHECK FOR CORRECT SJB OPERATION
- Ignition OFF.
- Disconnect all the SJB connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the SJB 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 SJB. REFER to Body Control Systems. 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.
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