Pinpoint Test B: One Or Both High Beams Are Inoperative

Headlamps

Pinpoint Test B: One or Both High Beams are Inoperative

Refer to Wiring Diagram Set 85, Headlamps for schematic and connector information Electrical Diagrams.

Normal Operation

Voltage is provided at all times to the switch and coil sides of the high beam relay. The Body Control Module (BCM) sends a voltage signal to the multifunction switch to monitor for a high beam request. The multifunction switch routes the voltage signal to ground when placed in the HIGH BEAM position. When the headlamps are on and the BCM (Body Control Module) detects a request for the high beams, the BCM (Body Control Module) provides ground for the high beam relay coil. When the high beam relay energizes, voltage is routed through Battery Junction Box (BJB) fuses 37 (10A) (LH high beam) and 38 (10A) (RH high beam) to the headlamps.

- DTC B109A:12 (High Beam Relay: Circuit Short To Battery)- a continuous and on-demand DTC that sets when the BCM (Body Control Module) detects a short to voltage from the high beam relay coil ground controlled circuit.

- DTC B109A:14 (High Beam Relay: Circuit Short To Ground Or Open)- a continuous and on-demand DTC that sets when the BCM (Body Control Module) detects an open from the high beam relay coil ground controlled circuit.

This pinpoint test is intended to diagnose the following:

- Fuse

- Wiring, terminals or connectors

- High beam relay

- Multifunction switch

- Headlamp assembly

- BJB (Battery Junction Box)

- BCM (Body Control Module)

PINPOINT TEST B : ONE OR 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.

B1 CHECK THE LOW BEAM OPERATION

- Ignition ON.

- Place the headlamp switch in the HEADLAMPS ON position.

Do both low beams illuminate?

Yes
If an individual high beam is inoperative, VERIFY the BJB (Battery Junction Box) fuse 37 (10A) (LH high beam) or fuse 38 (10A) (RH high beam) is OK. If OK, GO to B2. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short Electrical Diagrams.

If both high beams are inoperative, VERIFY the BJB (Battery Junction Box) fuse 17 (20A) is OK. If OK, GO to B4. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short Electrical Diagrams.

No
GO to Pinpoint Test A Pinpoint Test A: One Or Both Low Beams Are Inoperative.

B2 CHECK FOR VOLTAGE TO THE HEADLAMP

- Place the headlamp switch in the HEADLAMPS OFF position.

- Ignition OFF.

- Disconnect: Inoperative Headlamp.

- Ignition ON.

- Place the headlamp switch in the HEADLAMPS ON position and the multifunction switch in the HIGH BEAM position.

- Measure the voltage between the LH headlamp C1021-3, circuit CBB37 (WH), harness side and ground; or between the RH headlamp C1041-3, circuit CBB38 (GY/BN), harness side and ground.





Is the voltage greater than 10 volts?

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

No
GO to B3.

B3 CHECK FOR VOLTAGE TO THE HIGH BEAM FUSE

- Ignition OFF.

- Disconnect: BJB (Battery Junction Box) Fuse 37 (10A) (LH high beam) or Fuse 38 (10A) (RH high beam).

- Measure the voltage between the BJB (Battery Junction Box) fuse 37 (10A) (LH high beam), circuit CLF08 (YE/VT), input side and ground; or between the BJB (Battery Junction Box) fuse 38 (10A) (RH high beam), circuit CLF08 (YE/VT), input side and ground.





Is the voltage greater than 10 volts?

Yes
REPAIR circuit CBB37 (WH) (LH headlamp) or circuit CBB38 (GY/BN) (RH headlamp) for an open. TEST the system for normal operation.

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

B4 CHECK THE BCM (Body Control Module) MULTIFUNCTION SWITCH PID

- Enter the following diagnostic mode on the scan tool: BCM (Body Control Module) DataLogger.

- Monitor the BCM (Body Control Module) multifunction switch input PID (HIGH_BEAM_SW) while placing the multifunction switch in the HIGH BEAM position.

Does the PID indicate a request for high beams?

Yes
GO to B5.

No
GO to B10.

B5 CHECK THE HIGH BEAM RELAY

- Place the headlamp switch in the HEADLAMPS OFF position.

- Ignition OFF.

- Disconnect: High Beam Relay.

- Substitute a known good relay.

- Ignition ON.

- Place the headlamp switch in the HEADLAMPS ON position and the multifunction switch in the HIGH BEAM position.

Do the high beams illuminate?

Yes
REMOVE the known good relay. INSTALL a new high beam relay. TEST the system for normal operation.

No
REMOVE the known good relay. GO to B6.

B6 CHECK FOR VOLTAGE TO THE HIGH BEAM RELAY

- Ignition OFF.

- Measure the voltage between the high beam relay pin 1, circuit SBB21 (GY/RD), BJB (Battery Junction Box) face side and ground; and between the high beam relay pin 3, circuit SBB17 (YE/RD), BJB (Battery Junction Box) face side and ground.





Are the voltages greater than 10 volts?

Yes
GO to B7.

No
INSTALL a new BJB (Battery Junction Box). CLEAR the DTCs. TEST the system for normal operation.

B7 BYPASS THE HIGH BEAM RELAY

- Connect a fused jumper wire between the high beam relay pin 3, circuit SBB17 (YE/RD), BJB (Battery Junction Box) face side and the high beam relay pin 5, circuit CLF08 (YE/VT), BJB (Battery Junction Box) face side.





Do the high beams illuminate?

Yes
REMOVE the jumper wire. GO to B8.

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

B8 CHECK THE HIGH BEAM RELAY COIL GROUND CONTROLLED CIRCUIT FOR A SHORT TO VOLTAGE

- Disconnect: BCM (Body Control Module) C2280D.

- Ignition ON.

- Measure the voltage between the BCM (Body Control Module) C2280D-11, circuit CLF02 (GY/BN), harness side and ground.





Is any voltage present?

Yes
REPAIR circuit CLF02 (GY/BN) for a short to voltage. CYCLE the ignition ON then OFF. CLEAR the DTCs. TEST the system for normal operation.

No
GO to B9.

B9 CHECK THE HIGH BEAM RELAY COIL GROUND CONTROLLED CIRCUIT FOR AN OPEN

- Ignition OFF.

- Connect: High Beam Relay.

- Ignition ON.

- Measure the voltage between the BCM (Body Control Module) C2280D-11, circuit CLF02 (GY/BN), harness side and ground.





Is the voltage greater than 10 volts?

Yes
GO to B13.

No
REPAIR circuit CLF02 (GY/BN) for an open. CLEAR the DTCs. TEST the system for normal operation.

B10 BYPASS THE MULTIFUNCTION SWITCH

- Ignition OFF.

- Disconnect: Multifunction Switch C202A.

- Ignition ON.

- Connect a fused jumper wire between the multifunction switch C202A-10, circuit CLF17 (WH/OG), harness side and the multifunction switch C202A-9, circuit GD115 (BK/GY), harness side.





- Enter the following diagnostic mode on the scan tool: BCM (Body Control Module) DataLogger.

- Monitor the BCM (Body Control Module) multifunction switch input PID (HIGH_BEAM_SW).

Does the PID indicate a request for high beams?

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

No
REMOVE the jumper wire. GO to B11.

B11 BYPASS THE MULTIFUNCTION SWITCH GROUND CIRCUIT

- Connect a fused jumper wire between the multifunction switch C202D-10, circuit CLF17 (WH/OG), harness side and ground.





- Enter the following diagnostic mode on the scan tool: BCM (Body Control Module) DataLogger.

- Monitor the BCM (Body Control Module) multifunction switch input PID (HIGH_BEAM_SW).

Does the PID indicate a request for high beams?

Yes
REMOVE the jumper wire. REPAIR circuit GD115 (BK/GY) for an open. TEST the system for normal operation.

No
REMOVE the jumper wire. GO to B12.

B12 CHECK THE HIGH BEAM REQUEST INPUT CIRCUIT FOR AN OPEN

- Ignition OFF.

- Disconnect: BCM (Body Control Module) C2280F.

- Measure the resistance between the multifunction switch C202A-10, circuit CLF17 (WH/OG), harness side and the BCM (Body Control Module) C2280F-10, circuit CLF17 (WH/OG), harness side.





Is the resistance less than 5 ohms?

Yes
GO to B13.

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

B13 CHECK FOR CORRECT BCM (Body Control Module) OPERATION

- Disconnect all the BCM (Body Control Module) connectors.

- Check for:
- corrosion

- damaged pins

- pushed-out pins


- Connect all the BCM (Body Control 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 BCM (Body Control 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.