When the body control module (BCM) receives a ground signal from the multifunction high beam or flash to pass (FTP) switch commanding to illuminate the high beam headlamps, the BCM will energize the high beam relay by grounding the high beam relay control circuit.
This diagnostic procedure supports the following DTCs:
• | DTC B2582 Headlamp High Beam Control Circuit Low |
• | DTC B2583 Headlamp High Beam Control Circuit High |
The battery voltage must be between 9-16 volts.
• | When the BCM receives a high beam headlamp OFF command and the high beam headlamp relay control circuit is shorted to ground |
• | When the BCM receives a high beam headlamp ON command and the high beam headlamp relay control circuit is shorted to voltage or open |
The high beam headlamps will not operate or will remain always ON.
• | This DTC will clear on current status after the condition for setting the fault is corrected. |
• | A history DTC will clear after 100 consecutive ignition cycles without a fault present. |
• | History and current DTCs can be cleared using a scan tool. |
The numbers below refer to the step numbers on the diagnostic table.
Listen for an audible click when the high beam relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
This step tests for voltage at the coil side of the high beam relay.
This step verifies that the BCM is providing ground to the high beam relay.
This step tests if ground is constantly being applied to the high beam relay.
This step tests if there is opposing voltage present or an open high beam relay control circuit.
After replacement of the BCM, you must calibrate the new module for proper operation.
Step | Action | Yes | No |
---|---|---|---|
Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics Connector End View Reference: Lighting Systems Connector End Views or Data Communication Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
Does the high beam relay turn ON and OFF with each command? | Go to Testing for Intermittent Conditions and Poor Connections | Go to Step 3 | |
Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 | |
Does the test lamp turn ON and OFF with each command? | Go to Step 8 | Go to Step 5 | |
Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 | |
Test the control circuit of the high beam relay for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 9 | |
7 | Test the control circuit of the high beam relay for a short to ground. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
8 | Inspect for poor connections at the high beam relay. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 11 |
9 | Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
10 | Repair the battery positive voltage circuit of the high beam relay. Refer to Wiring Repairs .. Did you complete the repair? | Go to Step 13 | -- |
11 | Replace the high beam relay. Refer to Relay Replacement . Did you complete the replacement? | Go to Step 13 | -- |
Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 13 | -- | |
13 |
Does the DTC reset? | Go to Step 2 | System OK |