Pinpoint Test A: Both High Beams Are Inoperative

Headlamps

Pinpoint Tests

Pinpoint Test A: Both High Beams Are Inoperative

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

Normal Operation

The Smart Junction Box (SJB) monitors the high beam request circuit from the multifunction switch. When the multifunction switch is placed in the HIGH BEAM position, the signal is routed to the ground circuit. The SJB then supplies voltage to the high beam headlamps.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Multifunction switch
- SJB



PINPOINT TEST A: BOTH HIGH BEAMS ARE INOPERATIVE

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

-------------------------------------------------
A1 CHECK FOR VOLTAGE TO THE MULTIFUNCTION SWITCH


- Ignition OFF.
- Disconnect: Multifunction Switch C202.
- Measure the voltage between the multifunction switch C202-6, circuit CLF17 (WH/OG), harness side and ground.




- Is the voltage greater than 10 volts?

Yes
GO to A2.

No
GO to A3.

-------------------------------------------------
A2 CHECK THE MULTIFUNCTION SWITCH


- Connect a fused jumper wire between the multifunction switch C202-6, circuit CLF17 (WH/OG), harness side and the multifunction switch C202-8, circuit GD145 (BK/BU), harness side.




- Place the headlamp switch in the HEADLAMPS ON position.
- Do the high beams illuminate?

Yes
REMOVE the jumper wire. INSTALL a new multifunction switch. REFER to Steering Column. TEST the system for normal operation.

No
REMOVE the jumper wire. REPAIR circuit GD145 (BK/BU) for an open. TEST the system for normal operation.

-------------------------------------------------
A3 CHECK THE HIGH BEAM REQUEST INPUT CIRCUIT FOR AN OPEN


- Disconnect: SJB C2280d.
- Measure the resistance between the multifunction switch C202-6, circuit CLF17 (WH/OG), harness side and the SJB C2280d-11, circuit CLF17 (WH/OG), harness side.




- Is the resistance less than 5 ohms?

Yes
GO to A4.

No
REPAIR circuit CLF17 (WH/OG) for an open. TEST the system for normal operation.

-------------------------------------------------
A4 CHECK FOR CORRECT SJB OPERATION


- 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.

-------------------------------------------------