Pinpoint Test D: One Low Beam Headlamp Is Inoperative - High Intensity Discharge (HID) Headlamps
Headlamps
Pinpoint Tests
Pinpoint Test D: One Low Beam Headlamp Is Inoperative - High Intensity Discharge (HID) Headlamps
Refer to Wiring Diagram Set 85, Headlamps for schematic and connector information. Diagrams By Number
Refer to Wiring Diagram Set 11, Fuse and Relay Information for schematic and connector information. Diagrams By Number
Normal Operation
When the Smart Junction Box (SJB) receives a request for the low beams, the SJB provides voltage to circuits 1338 (WH) and 1336 (LG/WH), through the Bussed Electrical Center (BEC), to the LH and RH High Intensity Discharge (HID) relays, respectively. Ground for the HID relays is provided through circuit 1205 (BK), which is routed through the BEC.
Voltage is supplied to the LH and RH HID relay switches through circuits 1055 (WH/LG) and 1056 (DB/LG).
When the HID relays are energized, voltage is routed to the LH and RH headlamps through circuits 2008 (PK/WH) (PK/BK for 5.4L) and 2009 (PK/WH).
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- HID relay
- BEC
- Ballast
- HID bulb
- Headlamp assembly
- SJB
PINPOINT TEST D: ONE LOW BEAM HEADLAMP IS INOPERATIVE - HID HEADLAMPS
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery.
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D1 CHECK THE HID RELAY
- Ignition OFF.
- Disconnect: Suspect HID Relay.
- Substitute a known good relay and recheck the low beam operation.
- Does the headlamp in question illuminate?
Yes
REMOVE the known good relay. INSTALL a new HID relay in question. TEST the system for normal operation.
No
REMOVE the known good relay. GO to D2.
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D2 CHECK THE HEADLAMP GROUND CIRCUIT
- Disconnect: Inoperative Headlamp.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the LH headlamp C1284-2, circuit 1205 (BK), harness side and ground; or between the RH headlamp C1285-2, circuit 1205 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to D5.
No
GO to D3.
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D3 CHECK CIRCUIT 1205 (BK) FOR AN OPEN (HEADLAMP TO BEC)
- Disconnect: BEC C1035c.
- Measure the resistance between the LH headlamp C1284-2, circuit 1205 (BK), harness side and the BEC C1035c-D5, circuit 1205 (BK), harness side; or between the RH headlamp C1285-2, circuit 1205 (BK), harness side and the BEC C1035c-D11, circuit 1205 (BK), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to D4.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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D4 CHECK CIRCUIT 1205 (BK) FOR AN OPEN (BEC TO GROUND)
- Measure the resistance between the BEC C1035c-F5 (LH headlamp), circuit 1205 (BK), harness side and ground; or between the BEC C1035c-E11 (RH headlamp), circuit 1205 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new BEC. CLEAR the DTCs. REPEAT the self-test.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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D5 CHECK FOR VOLTAGE TO THE HEADLAMP
- Connect: Negative Battery Cable.
- Connect: Suspect HID Relay.
- Place the headlamp switch in the HEADLAMPS ON position.
- Measure the voltage between the LH headlamp C1284-1, circuit 2008 (PK/WH) (PK/BK for 5.4L), harness side and ground; or between the RH headlamp C1285-1, circuit 2009 (PK/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to D17.
No
GO to D6.
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D6 CHECK THE HID RELAY GROUND CIRCUIT
- Place the headlamp switch in the OFF position.
- Disconnect: Negative Battery Cable.
- Disconnect: Suspect HID Relay.
- For 4.0L or 4.6L vehicles, measure the resistance between the LH HID relay pin 1, circuit 1205 (BK), harness side and ground; or between the RH HID relay pin 1, circuit 1205 (BK), harness side and ground.
- For 5.4L vehicles, measure the resistance between the LH HID relay pin 2, circuit 1205 (BK), harness side and ground; or between the RH HID relay pin 2, circuit 1205 (BK), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
GO to D8.
No
GO to D7.
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D7 CHECK CIRCUIT 1205 (BK) FOR AN OPEN (HID RELAY TO BEC)
- Disconnect: BEC C1035c.
- Measure the resistance between the suspect HID relay pin, harness side and the BEC, harness side as follows:
- Is the resistance less than 5 ohms?
Yes
INSTALL a new BEC. CLEAR the DTCs. REPEAT the self-test.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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D8 CHECK CIRCUIT 1336 (LG/WH) OR CIRCUIT 1338 (WH) FOR VOLTAGE
- Connect: Negative Battery Cable.
- Place the headlamp switch in the HEADLAMPS ON position.
- For 4.0L or 4.6L vehicles, measure the voltage between the LH HID relay pin 2, circuit 1338 (WH), harness side and ground; or between the RH HID relay pin 2, circuit 1336 (LG/WH), harness side and ground.
- For 5.4L vehicles, measure the voltage between the LH HID relay pin 1, circuit 1338 (WH), harness side and ground; or between the RH HID relay pin 1, circuit 1336 (LG/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to D15.
No
GO to D9.
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D9 CHECK CIRCUIT 1336 (LG/WH) OR CIRCUIT 1338 (WH) FOR A SHORT TO GROUND
- Place the headlamp switch in the OFF position.
- Disconnect: SJB C2280d.
- For 4.0L or 4.6L vehicles, measure the resistance between the LH HID relay pin 2, circuit 1338 (WH), harness side and ground; or between the RH HID relay pin 2, circuit 1336 (LG/WH), harness side and ground.
- For 5.4L vehicles, measure the resistance between the LH HID relay pin 1, circuit 1338 (WH), harness side and ground; or between the RH HID relay pin 1, circuit 1336 (LG/WH), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to D12.
No
GO to D10.
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D10 CHECK CIRCUIT 1336 (LG/WH) OR CIRCUIT 1338 (WH) FOR A SHORT TO GROUND (SJB TO BEC)
- Disconnect: BEC C1035a.
- For 4.0L or 4.6L vehicles, measure the resistance between the LH HID relay pin 2, circuit 1338 (WH), harness side and ground; or between the RH HID relay pin 2, circuit 1336 (LG/WH), harness side and ground.
- For 5.4L vehicles, measure the resistance between the LH HID relay pin 1, circuit 1338 (WH), harness side and ground; or between the RH HID relay pin 1, circuit 1336 (LG/WH), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
No
GO to D11.
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D11 CHECK CIRCUIT 1336 (LG/WH) OR CIRCUIT 1338 (WH) FOR A SHORT TO GROUND (BEC TO HEADLAMP)
- Disconnect: BEC C1035c.
- For 4.0L or 4.6L vehicles, measure the resistance between the LH HID relay pin 2, circuit 1338 (WH), harness side and ground; or between the RH HID relay pin 2, circuit 1336 (LG/WH), harness side and ground.
- For 5.4L vehicles, measure the resistance between the LH HID relay pin 1, circuit 1338 (WH), harness side and ground; or between the RH HID relay pin 1, circuit 1336 (LG/WH), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new BEC. CLEAR the DTCs. REPEAT the self-test.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
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D12 CHECK CIRCUIT 1336 (LG/WH) OR CIRCUIT 1338 (WH) FOR AN OPEN (BEC TO HID RELAY)
- Disconnect: BEC C1035c.
- Measure the resistance between the suspect HID relay pin, harness side and the BEC, harness side as follows:
- Is the resistance less than 5 ohms?
Yes
GO to D13.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
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D13 CHECK FOR VOLTAGE TO THE BEC
- Disconnect: BEC C1035a.
- Place the headlamp switch in the HEADLAMPS ON position.
- Measure the voltage between the BEC C1035a-F6 (LH headlamp), circuit 1338 (WH), harness side and ground; or between the BEC C1035a-F2 (RH headlamp), circuit 1336 (LG/WH), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
INSTALL a new BEC. CLEAR the DTCs. REPEAT the self-test.
No
GO to D14.
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D14 CHECK CIRCUIT 1336 (LG/WH) OR CIRCUIT 1338 (WH) FOR AN OPEN (SJB TO BEC)
- Place the headlamp switch in the OFF position.
- Disconnect: SJB C2280d.
- For an inoperative LH headlamp, measure the resistance between the BEC C1035a-F6, circuit 1338 (WH), harness side and the SJB C2280d-51, circuit 1338 (WH), harness side.
- For an inoperative RH headlamp, measure the resistance between the BEC C1035a-F2, circuit 1336 (LG/WH), harness side and the SJB C2280d-48, circuit 1336 (LG/WH), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to D19.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
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D15 CHECK CIRCUIT 1055 (WH/LG) OR CIRCUIT 1056 (DB/LG) FOR VOLTAGE
- Place the headlamp switch in the OFF position.
- For 4.0L or 4.6L vehicles, measure the voltage between the LH HID relay pin 3, circuit 1055 (WH/LG), harness side and ground; or between the RH HID relay pin 3, circuit 1056 (DB/LG), harness side and ground.
- For 5.4L vehicles, measure the voltage between the LH HID relay pin 3, circuit 1055 (WH/LG), harness side and ground; or between the RH HID relay pin 3, circuit 1056 (DB/LG), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
REPAIR circuit 2008 (PK/WH) (PK/BK for 5.4L) (LH headlamp) or circuit 2009 (PK/WH) (RH headlamp) for an open.
No
VERIFY the BEC fuse 54 (15A) (LH headlamp) or fuse 55 (15A) (RH headlamp) is OK. If OK, GO to D16. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short.
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D16 CHECK CIRCUIT 1055 (WH/LG) OR CIRCUIT 1056 (DB/LG) FOR AN OPEN
- Disconnect: BEC C1035c.
- Measure the resistance between the suspect HID relay pin, harness side and the BEC, harness side as follows:
- Is the resistance less than 5 ohms?
Yes
INSTALL a new BEC. CLEAR the DTCs. REPEAT the self-test.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
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D17 CHECK THE HEADLAMP HARNESS
- Place the headlamp switch in the OFF position.
- Inspect the headlamp harness for an open between the ballast and the vehicle harness connector.
- Is the headlamp harness OK?
Yes
GO to D18.
No
REPAIR or INSTALL a new headlamp assembly. REFER to Headlamp Assembly Service and Repair. TEST the system for normal operation.
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D18 CHECK THE BALLAST
- Substitute a known good ballast.
- Connect: Inoperative Headlamp.
- Place the headlamp switch in the HEADLAMPS ON position.
- Does the inoperative headlamp now illuminate?
Yes
INSTALL a new ballast. REFER to Headlamp Assembly Service and Repair. TEST the system for normal operation.
No
INSTALL a new HID bulb. REFER to Headlamp Bulb Service and Repair. TEST the system for normal operation.
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D19 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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