Headlamps Inoperative - High Beams V6
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics Connector End View Reference: Master Electrical Component List | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 |
Do the high beams illuminate? | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 |
3 | Is only one high beam headlamp inoperative? | Go to Step 14 | Go to Step 4 |
4 | Place the headlamp dimmer switch in to the flash to pass (FTP) position. Do the high beam headlamps illuminate? | Go to Step 7 | Go to Step 5 |
5 |
Do the high beam headlamps illuminate? | Go to Step 9 | Go to Step 6 |
6 |
Do the high beam headlamps illuminate? | Go to Step 10 | Go to Step 13 |
7 |
Do the high beam headlamps illuminate? | Go to Step 11 | Go to Step 8 |
8 | Test for poor connection, short to battery positive voltage or an open in the headlamp dimmer switch high beam signal circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 20 | Go to Step 19 |
9 |
Do the headlamps illuminate? | Go to Step 11 | Go to Step 19 |
10 | Test for a short to battery positive voltage, a poor connection or an open in the headlamp high beam relay control circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 20 | Go to Step 12 |
11 | Inspect for a poor connection at the harness connector of the multifunction turn signal switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 20 | Go to Step 15 |
12 | Inspect for a poor connection at the harness connector of the high beam relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 20 | Go to Step 16 |
13 | Inspect for a poor connection at the harness connectors of the underhood fuse block. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | Go to Step 20 | Go to Step 17 |
14 | Inspect the inoperative high beam headlamp voltage supply and ground circuit for a high resistance, short to ground, short to battery positive voltage or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 20 | Go to Step 18 |
15 | Replace the multifunction turn signal switch. Refer to Turn Signal Multifunction Switch Replacement . Did you complete the replacement? | Go to Step 20 | Go to Step 3 |
16 | Replace the high beam relay. Refer to Relay Replacement . Did you complete the replacement? | Go to Step 20 | -- |
17 | Replace the underhood fuse block. Refer to Relay Replacement . Did you complete the repair? | Go to Step 20 | -- |
18 | Replace the inoperative high beam headlamp. Refer to Headlamp Assembly or Headlamp Bulb Replacement . Did you complete the replacement? | Go to Step 20 | -- |
19 | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 20 | -- |
20 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
Headlamps Inoperative - High Beams V8 High Beam PCB Relay
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
High Beam Headlamp Relay Control Circuit | 2 | 1 | B2580 | -- |
| ||||
Circuit/System Description
Voltage is applied at all times to the high beam headlamp relay from battery voltage. When the dimmer switch or the flash to pass switch send a ground input to the BCM, the BCM sends a ground output to the high beam relay. The high beam relay is activated then the switch side of the relay closes and turns on the lights.
Reference Information
Schematic Reference
Headlights/Daytime Running Lights (DRL) Schematics
Connector End View Reference
Lighting Systems Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
- Ignition ON, turn the park lamps and head lamps ON. Switch the head lamps from low to high beam. The low beam and high beam lamps should illuminate.
- Observe the scan tool high beam lamps switch parameter while switching the head lamps from low to high beam. The reading should change between ON and OFF.
| ⇒ | If the high beam lamps do not illuminate and the high beam lamp switch parameter does not change while switching the head lamps from low to high beam--Test input side of BCM for inoperative condition in Circuit/System Testing. |
| ⇒ | If the high beam lamps do not illuminate and the high beam lamp switch parameter does change between ON and OFF while switching the head lamps from low to high beam--Test output side of BCM for inoperative condition in Circuit/System Testing. |
Circuit/System Testing
Test Input Side of BCM For Inoperative High Beam Lamps
- Ignition OFF, disconnect the malfunction turn signal lever harness connector at the switch.
- Test for less than 1 ohm of resistance between the ground circuit terminal D and ground.
- Ignition ON, verify the scan tool high beam lamp switch parameter displays OFF.
- Install a 3A fused jumper wire between the signal circuit terminal E and the ground circuit terminal D. Verify the scan tool high beam switch parameter displays closed.
- If all circuits test normal, test or replace the multifunction turn signal lever.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If not the specified value, test the signal circuit terminal E for a short to ground. If the circuit tests normal, replace the body control module. |
| ⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the body control module. |
Test Output Side of BCM For Inoperative High Beam Lamps
- Disconnect the harness connector at both high beam lamps.
- Test for less than 1.0 ohm of resistance between the appropriate high beam lamp ground circuit terminal B and ground.
- Connect a test lamp between the control circuit terminal A and ground.
- Command the high beam lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
- If all circuits test normal, replace the appropriate high beam lamp bulb socket.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BEC. |
| ⇒ | If the test lamp is always OFF and the circuit fuse is good, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the BEC. |
| ⇒ | If the test lamp is always OFF and the circuit fuse is open, test the control circuit for a short to ground. If the circuit tests normal, replace the appropriate high beam lamp bulb socket. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
