Pinpoint Test E: The High Beam(s) Are Always On
Headlamps
Pinpoint Tests
Pinpoint Test E: The High Beam(s) Are Always On
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 reference signal to the multifunction switch through circuits CLF27 (GN/BN) and CLF17 (WH/OG). When the multifunction switch is placed in the FLASH-TO-PASS or HIGH BEAM position, the voltage signal is routed to ground. When the SJB detects a request for flash-to-pass or high beams (when the low beams are on), the SJB energizes the high beam relay (integrated into the SJB), which routes voltage through circuit CLF08 (YE/VT) to the headlamps.
NOTE: For vehicles equipped with High Intensity Discharge (HID) headlamps, if circuit CLF08 (YE/VT) is supplied voltage when the headlamps are not on, the headlamps do not illuminate. Circuit CLF08 (YE/VT) only supplies voltage to activate the high beam shutters within the headlamp assemblies. The low beams must be on for light to illuminate from the headlamps.
- DTC B1510 (Flash To Pass Switch Circuit Short to Ground) - an on-demand DTC that sets when the SJB detects the flash-to-pass request input circuit is short to ground.
- DTC B2A23 (High Beam Input Circuit Short to Ground) - an on-demand DTC that sets when the SJB detects a short to ground on the high beam request input circuit.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Multifunction switch
- SJB
PINPOINT TEST E: THE HIGH BEAM(S) ARE ALWAYS ON
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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E1 CHECK FOR DTC B1510 OR DTC B2A23
- Review the DTCs retrieved from the SJB self-test.
- Was DTC B1510 or DTC B2A23 retrieved?
Yes
GO to E2.
No
For vehicles with halogen headlamps, GO to E4.
For vehicles with HID headlamps, GO to E5.
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E2 CHECK THE MULTIFUNCTION SWITCH
- Ignition OFF.
- Disconnect: Multifunction Switch C202.
- Ignition ON.
- Do the high beams continue to illuminate?
Yes
GO to E3.
No
INSTALL a new multifunction switch. CLEAR the DTCs. REPEAT the self-test.
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E3 CHECK THE HIGH BEAM AND FLASH-TO-PASS REQUEST INPUT CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: SJB C2280b.
- Measure the resistance between the multifunction switch C202-6, circuit CLF17 (WH/OG), harness side and ground; and between the multifunction switch C202-4, circuit CLF27 (GN/BN), harness side and ground.
- Are the resistances greater than 10,000 ohms?
Yes
GO to E6.
No
REPAIR the circuit in question for a short to ground. CLEAR the DTCs. REPEAT the self-test.
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E4 CHECK THE SJB HIGH BEAM OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE (HALOGEN HEADLAMPS)
- Ignition OFF.
- Disconnect: SJB C2280e.
- Ignition ON.
- Do the high beams continue to illuminate?
Yes
REPAIR circuit CLF08 (YE/VT) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to E6.
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E5 CHECK THE SJB HIGH BEAM OUTPUT CIRCUIT FOR A SHORT TO VOLTAGE (HID HEADLAMPS)
NOTE: If only an individual high beam is always on, install a new headlamp assembly. Refer to Headlamp Assembly Service and Repair.
- Ignition OFF.
- Disconnect: LH or RH Headlamp.
- Disconnect: SJB C2280e.
- Ignition ON.
- Measure the voltage between the LH headlamp C1284-1, circuit CLF08 (YE/VT), harness side and ground; or between the RH headlamp C1285-1, circuit CLF08 (YE/VT), harness side and ground.
- Is any voltage present?
Yes
REPAIR circuit CLF08 (YE/VT) for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to E6.
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E6 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. 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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