Pinpoint Test B: Both High Beams Are Inoperative
Headlamps
Pinpoint Test B: Both High Beams Are Inoperative
Refer to Wiring Diagrams Set 85, Headlamps for schematic and connector information. Electrical Diagrams
Normal Operation
When the headlamp switch is in the HEADLAMPS ON position, the Instrument Cluster (IC) receives a voltage signal, indicating the headlamps are on. The IC (Instrument Cluster) then monitors the high beam request circuit from the multifunction switch by sending voltage signals on 2 circuits to the multifunction switch (flash-to-pass request input and high beam request input).
When the multifunction switch is placed in the HIGH BEAM position, it passes through the FLASH-TO-PASS position first. When the multifunction switch is in the FLASH-TO-PASS position, the voltage signal for that circuit is routed to ground, indicating a request for the flash-to-pass feature. When the multifunction switch is placed in the HIGH BEAM position, both input circuits are routed to ground, indicating to the IC (Instrument Cluster) to change from the low beams to the high beams (or from the high beams to the low beams, if the high beams are already on).
Both input circuits to the IC (Instrument Cluster) must be grounded for the IC (Instrument Cluster) to switch from the low beams to the high beams, however, the flash-to-pass request must be received first.
The high beam relay coil is provided voltage when the ignition is in RUN. The IC (Instrument Cluster) provides ground for the high beam relay coil when the high beams are requested. The Battery Junction Box (BJB) fuse 8 (15A) provides voltage to the relay switch. When the relay is energized, voltage is provided to the high beams.
- DTC B1568 (Lamp Headlamp High-Beam Circuit Open)- a continuous DTC that sets when the IC (Instrument Cluster) detects no voltage from the high beam relay coil ground controlled circuit (open).
- DTC B1569 (Lamp Headlamp High-Beam Circuit Short to Battery)- a continuous DTC that sets when the IC (Instrument Cluster) detects a short to voltage from the high beam relay coil ground controlled circuit.
- DTC B2A23 (High Beam Input Circuit Short to Ground)- an on-demand DTC that sets when the IC (Instrument Cluster) detects a short to ground from the high beam request input circuit.
This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- High beam relay
- Multifunction switch
- IC (Instrument Cluster)
PINPOINT TEST B : 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 the low beams illuminate?
Yes
GO to B2.
No
GO to Pinpoint Test A. Pinpoint Test A: Both Low Beams Are Inoperative
B2 CHECK FOR DTC B2A23
- Place the headlamp switch in the OFF position.
- Review the DTCs retrieved from the IC (Instrument Cluster) self-test.
Is DTC B2A23 present?
Yes
GO to B3.
No
GO to B5.
B3 CHECK THE MULTIFUNCTION SWITCH
- Ignition OFF.
- Disconnect: Multifunction Switch C202.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC (Instrument Cluster) Self-Test.
- Repeat the IC (Instrument Cluster) self-test.
Is DTC B2A23 still present?
Yes
GO to B4.
No
INSTALL a new multifunction switch. TEST the system for normal operation.
B4 CHECK THE HIGH BEAM REQUEST INPUT CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: IC (Instrument Cluster) C220A.
- Measure the resistance between the multifunction switch C202-8, circuit 91S-LE14 (BK/OG), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to B16.
No
REPAIR circuit 91S-LE14 (BK/OG) for an open. TEST the system for normal operation.
B5 CHECK THE HIGH BEAM INDICATOR
- Place the headlamp switch in the HEADLAMPS ON position.
- NOTE: If the high beam indicator does not stay on when the multifunction switch is released, repeat this step one more time.
Place the multifunction switch in the FLASH-TO-PASS and then HIGH BEAM position then release the multifunction switch.
Does the high beam indicator illuminate for both positions and remain illuminated when the multifunction switch is released?
Yes
GO to B11.
No
GO to B6.
B6 CHECK FOR A VOLTAGE SIGNAL TO THE IC (Instrument Cluster)
- Place the headlamp switch in the OFF position.
- Ignition OFF.
- Disconnect: IC (Instrument Cluster) C220A.
- Ignition ON.
- Place the headlamp switch in the HEADLAMPS ON position.
- Measure the voltage between the IC (Instrument Cluster) C220A-1, circuit 15S-LE21 (GN/BK), harness side and ground.
Is the voltage greater than 10 volts?
Yes
GO to B7.
No
REPAIR circuit 15S-LE21 (GN/BK) for an open. TEST the system for normal operation.
B7 CHECK FOR VOLTAGE SIGNALS TO THE MULTIFUNCTION SWITCH
- Place the headlamp switch in the OFF position.
- Ignition OFF.
- Connect: IC (Instrument Cluster) C220A.
- Disconnect: Multifunction Switch C202.
- Ignition ON.
- Measure the voltage between the multifunction switch C202-8, circuit 91S-LE14 (BK/OG), harness side and ground; and between the multifunction switch C202-9, circuit 91S-LE25 (BK/BU), harness side and ground.
Are the voltages greater than 10 volts?
Yes
GO to B9.
No
GO to B8.
B8 CHECK THE FLASH-TO-PASS AND HIGH BEAM REQUEST INPUT CIRCUITS FOR AN OPEN
- Ignition OFF.
- Disconnect: IC (Instrument Cluster) C220A.
- Measure the resistance between the multifunction switch C202-8, circuit 91S-LE14 (BK/OG), harness side and the IC (Instrument Cluster) C220A-3, circuit 91S-LE14 (BK/OG), harness side; and between the multifunction switch C202-9, circuit 91S-LE25 (BK/BU), harness side and the IC (Instrument Cluster) C220A-2, circuit 91S-LE25 (BK/BU), harness side.
Are the resistances less than 5 ohms?
Yes
GO to B16.
No
REPAIR the circuit in question for an open. TEST the system for normal operation.
B9 BYPASS THE MULTIFUNCTION SWITCH
- Place the headlamp switch in the HEADLAMPS ON position.
- Connect a fused jumper wire between the multifunction switch C202-9, circuit 91S-LE25 (BK/BU), harness side and ground.
- Connect then remove a fused jumper wire between the multifunction switch C202-8, circuit 91S-LE14 (BK/OG), harness side and ground.
- Remove the first jumper wire.
Does the high beam indicator remain illuminated with the jumper wires removed?
Yes
GO to B10.
No
GO to B16.
B10 CHECK FOR VOLTAGE TO THE MULTIFUNCTION SWITCH USING THE CONNECTOR GROUND
- Measure the voltage between the multifunction switch C202-8, circuit 91S-LE14 (BK/OG), harness side and the multifunction switch C202-10, circuit 91-LG27 (BK/GN), harness side.
Is the voltage greater than 10 volts?
Yes
INSTALL a new multifunction switch. TEST the system for normal operation.
No
REPAIR the multifunction switch ground circuit for an open. TEST the system for normal operation.
B11 CHECK THE HIGH BEAM RELAY
- Place the headlamp switch in the OFF position.
- Disconnect: High Beam Relay.
- Substitute a known good relay.
- NOTE: Make sure the high beam indicator is illuminated.
Place the headlamp switch in the HEADLAMPS ON 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 B12.
B12 CHECK FOR BATTERY VOLTAGE TO THE HIGH BEAM RELAY
- Ignition OFF.
- Measure the voltage between the high beam relay pin 3, circuit 30-LE13 (RD), BJB (Battery Junction Box) face side and ground.
Is the voltage greater than 10 volts?
Yes
GO to B13.
No
VERIFY the BJB (Battery Junction Box) fuse 8 (15A) is OK. If OK, REPAIR circuit 30-LE13 (RD) for an open. TEST the system for normal operation. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. Electrical Diagrams
B13 CHECK FOR VOLTAGE TO THE HIGH BEAM RELAY COIL
- Ignition ON.
- Measure the voltage between the high beam relay pin 1, circuit 90-LE12 (RD/YE), BJB (Battery Junction Box) face side and ground.
Is the voltage greater than 10 volts?
Yes
GO to B14.
No
REPAIR the high beam relay coil voltage supply circuit for an open. TEST the system for normal operation.
B14 BYPASS TO THE HIGH BEAM RELAY
- Connect a fused jumper wire between the high beam relay pin 3, circuit 30-LE13 (RD), BJB (Battery Junction Box) face side and the high beam relay pin 5, circuit 30S-LE13 (RD/BU), BJB (Battery Junction Box) face side.
Do the high beams illuminate?
Yes
REMOVE the jumper wire. GO to B15.
No
REMOVE the jumper wire. REPAIR circuit 30S-LE13 (RD/BU) for an open. TEST the system for normal operation.
B15 CHECK FOR VOLTAGE TO THE IC (Instrument Cluster)
- Ignition OFF.
- Connect: High Beam Relay.
- Disconnect: IC (Instrument Cluster) C220A.
- Ignition ON.
- Measure the voltage between the IC (Instrument Cluster) C220A-7, circuit 15S-LE12 (GN/YE), harness side and ground.
Is the voltage greater than 10 volts?
Yes
GO to B16.
No
REPAIR circuit 15S-LE12 (GN/YE) for an open. TEST the system for normal operation.
B16 CHECK FOR CORRECT IC (Instrument Cluster) OPERATION
- Disconnect all the IC (Instrument Cluster) connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the IC (Instrument Cluster) 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 IC (Instrument Cluster). 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.