Pinpoint Test C: One High Beam Headlamp Is Inoperative

Headlamps

Pinpoint Test C: One High Beam Headlamp Is Inoperative

Refer to Wiring Diagram Set 85, Headlamps/Autolamps for schematic and connector information. [1][2]Diagrams By Number

Normal Operation

When low beams are on and the Smart Junction Box (SJB) detects the multifunction switch in the HIGH BEAM position, the SJB (Smart Junction Box) energizes an internal relay. When the relay is energized, the relay routes voltage to the headlamps.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors

- Headlamp assembly

PINPOINT TEST C : ONE HIGH BEAM HEADLAMP IS INOPERATIVE

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

C1 CHECK FOR VOLTAGE TO THE HEADLAMP

- Ignition OFF.

- Disconnect: Inoperative Headlamp.

- Place the headlamp switch in the HEADLAMPS ON position.

- Place the multifunction switch in the HIGH BEAM position.

- Measure the voltage between the LH headlamp C1021-7, circuit CLF08 (YE/VT), harness side and ground; or between the RH headlamp C1041-7, circuit CLF08 (YE/VT), harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to C2.

No
REPAIR circuit CLF08 (YE/VT) for an open. TEST the system for normal operation.

C2 CHECK FOR VOLTAGE TO THE HEADLAMP USING THE HIGH BEAM GROUND PIN

- Measure the voltage between the LH headlamp C1021-7, circuit CLF08 (YE/VT), harness side and the LH headlamp C1021-4, circuit GD121 (BK/YE), harness side; or between the RH headlamp C1041-7, circuit CLF08 (YE/VT), harness side and the RH headlamp C1041-4, circuit GD123 (BK/GY), harness side.





Is the voltage greater than 10 volts?

Yes
REPAIR or INSTALL a new headlamp assembly. REFER to Headlamp Assembly . TEST the system for normal operation.

No
REPAIR circuit GD121 (BK/YE) (LH headlamp) or circuit GD123 (BK/GY) (RH headlamp) for an open. TEST the system for normal operation.