Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
- 2: Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.
- 3: This step determines if an ignition switch power mode condition exists. The specified procedure will determine which diagnostic path is to be followed.
- 4: This step determines if a Body Control Module (BCM) DTC based diagnostic path or a symptom based diagnostic path are to be followed.
- 5: The presence of DTCs which begin with U indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.
- 6: This step displays stored system related DTCs to be diagnosed.
- 7: This step will display a stored system related DTC to be diagnosed.
| Step | Action | Yes | No |
|---|---|---|---|
| 1 | Install a scan tool. Does the scan tool power up? | Go to Step 2 | Go to SCAN TOOL DOES NOT POWER UP in Data Link Communications |
| 2 | Turn ON the ignition, with the engine OFF. Attempt to establish communication with the body control module. Does the scan tool communicate with the body control module? | Go to Step 3 | Go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 Device (W/O Immobilizer) in Data Link Communications |
| 3 | IMPORTANT: The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode. Access the Class 2 Power Mode in the Diagnostic Circuit Check on the scan tool. Rotate the ignition switch through all positions while observing the ignition switch power mode parameter. Does the ignition switch parameter reading match the ignition switch position for all switch positions? | Go to Step 4 | Go to POWER MODE MISMATCH in Body Control System |
| 4 | Select the body control module display DTCs function on the scan tool. Does the scan tool display any DTCs? | Go to Step 5 | Go to Symptoms - Lighting Systems |
| 5 | Does the scan tool display any DTCs which begin with a U ? | Go to DIAGNOSTIC TROUBLE CODE (DTC) LIST in Data Link Communications | Go to Step 6 |
| 6 | Does the scan tool display DTC B1000, B1004, B1007, B1009, B1397, B1420 or B1440? | Go to DIAGNOSTIC TROUBLE CODE (DTC) LIST in Body Control System | Go to Step 7 |
| 7 | Does the scan tool display DTC B1017? | Go to DIAGNOSTIC TROUBLE CODE (DTC) LIST in Doors | Go to Diagnostic Trouble Code (DTC) List |
| IMPORTANT |
|---|
| The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode. |
Diagnostic System Check - Lighting Systems
The numbers below refer to the step numbers on the diagnostic table.
- 3: Tests for an open in the TBC 5 battery positive voltage supply circuit within the body wiring harness extension harness.
- 4: Tests for voltage at the LED dimming signal circuit.
- 5: Tests for voltage at the LED dimming signal circuit when the headlamp switch is in the OFF position.
- 11: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Interior Lights Dimming Schematics | |||
| 1 | Did you perform the Lighting Systems Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. Use the scan tool to control the backlight dimming. Activate the affected control switch. Does the control switch indicator lamp respond to the scan tool output control? | Go to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS in Wiring Systems | Go to Step 3 |
| 3 | Test the TBC 5 battery positive supply voltage circuit of the body wiring harness extension harness for continuity. Refer to CIRCUIT TESTING in Wiring Systems. Is continuity present? | Go to Step 4 | Go to Step 7 |
| 4 | Turn the headlamp switch to PARK. Adjust the IP dimmer switch to the full illumination position. Probe the LED dimming signal circuit with a test lamp connected to a good ground. Does the test lamp illuminate? | Go to Step 5 | Go to Step 9 |
| 5 | Turn the headlamp switch to the OFF position. Ensure that there is sufficient light to the ambient light sensor to prevent ALC activation. Probe the LED dimming signal circuit with a test lamp connected to a good ground. Does the test lamp illuminate? | Go to Step 6 | Go to Step 8 |
| 6 | Test the LED dimming signal circuit for a short to voltage. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 8 |
| 7 | Inspect for poor connections at the body wiring harness extension harness connectors. Refer to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS and CONNECTOR REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 10 |
| 8 | Inspect for poor connections at the harness connector of the BCM. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 12 | Go to Step 11 |
| 9 | Repair the open, high resistance or short to ground in the LED dimming signal circuit. Refer to WIRING REPAIRS in Wiring Systems. Did you complete the repair? | Go to Step 12 | |
| 10 | Replace the body wiring harness extension harness to the BCM. Refer to BODY WIRING HARNESS EXTENSION REPLACEMENT - BCM in Body Control System. Did you complete the replacement? | Go to Step 12 | |
| 11 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 12 | |
| 12 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B0951
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step test determines if an open or short to ground exists.
- 3: This step test determines if a short to ground exists in the lamp wiring or internally within the BCM.
- 4: This step test determines if an open exists in the body wiring harness extension harness or internally within the BCM.
- 8: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Interior Lights Schematics | |||
| 1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Inspect the TBC 4 fuse in the rear fuse block. Is the fuse good? | Go to Step 4 | Go to Step 3 |
| 3 | Test the inadvertent power courtesy lamps supply voltage circuit for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 5 |
| 4 | Test the TBC 4 battery positive supply voltage circuit at the body wiring harness extension harness connector at the BCM for battery voltage. Refer to CIRCUIT TESTING in Wiring Systems. Is battery voltage present? | Go to Step 5 | Go to Step 6 |
| 5 | Inspect for poor connections at the harness connectors of the BCM. Refer to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS and CONNECTOR REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 8 |
| 6 | Inspect for poor connections at the body wiring harness extension harness connectors. Refer to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS and CONNECTOR REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 9 | Go to Step 7 |
| 7 | Replace the body wiring harness extension harness to the BCM. Refer to BODY WIRING HARNESS EXTENSION REPLACEMENT - BCM in Body Control System. Did you complete the replacement? | Go to Step 9 | |
| 8 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 9 | |
| 9 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B1480
The numbers below refer to the step numbers on the diagnostic table.
- 2: Listen for an audible click when the front fog lamp relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
- 3: Tests for voltage at the coil side of the front fog lamp relay.
- 4: Verifies that the body control module (BCM) is providing ground to the front fog lamp relay.
- 5: Tests if ground is constantly being applied to the front fog lamp relay.
- 6: Tests if there is opposing voltage present or an open in the front fog lamp relay control circuit.
- 12: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Fog Lights Schematics | |||
| 1 | Did you perform the Lighting Systems Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, command the front fog lamp relay ON and OFF. Does the front fog lamp relay turn ON and OFF with each command? | Go to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS in Wiring Systems | Go to Step 3 |
| 3 | Turn OFF the ignition. Disconnect the front fog lamp relay. Turn ON the ignition, with the engine OFF. Probe the battery positive voltage circuit of the front fog lamp relay with a test lamp that is connected to a good ground. Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 |
| 4 | Connect a test lamp between the control circuit of the front fog lamp relay and the battery positive voltage circuit of the front fog lamp relay. With a scan tool, command the front fog lamp relay ON and OFF. Does the test lamp turn ON and OFF with each command? | Go to Step 8 | Go to Step 5 |
| 5 | Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 |
| 6 | Test the control circuit of the front fog lamp relay for a short to voltage or an open. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
| 7 | Test the control circuit of the front fog lamp relay for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
| 8 | Inspect for poor connections at the front fog lamp relay. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. 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 BCM. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
| 10 | Repair the battery positive voltage circuit of the front fog lamp relay. Refer to WIRING REPAIRS in Wiring Systems. Did you complete the repair? | Go to Step 13 | |
| 11 | Replace the front fog lamp relay. Refer to Fog Lamp Relay Replacement (RPO T96) Fog Lamp Relay Replacement (RPO T79) . Did you complete the replacement? | Go to Step 13 | |
| 12 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 13 | |
| 13 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2530
The numbers below refer to the step numbers on the diagnostic table.
- 2: Listen for an audible click when the rear fog lamp relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
- 3: Tests for voltage at the coil side of the rear fog lamp relay.
- 4: Verifies that the body control module (BCM) is providing ground to the rear fog lamp relay.
- 5: Tests if ground is constantly being applied to the rear fog lamp relay.
- 6: Tests if there is opposing voltage present or an open in the rear fog lamp relay control circuit.
- 12: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Fog Lights Schematics | |||
| 1 | Did you perform the Lighting Systems Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, command the rear fog lamp relay ON and OFF. Does the rear fog lamp relay turn ON and OFF with each command? | Go to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS in Wiring Systems | Go to Step 3 |
| 3 | Turn OFF the ignition. Disconnect the rear fog lamp relay. Turn ON the ignition, with the engine OFF. Probe the battery positive voltage circuit of the rear fog lamp relay with a test lamp that is connected to a good ground. Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 |
| 4 | Connect a test lamp between the control circuit of the high beam relay and the battery positive voltage circuit of the rear fog lamp relay. With a scan tool, command the rear fog lamp relay ON and OFF. Does the test lamp turn ON and OFF with each command? | Go to Step 8 | Go to Step 5 |
| 5 | Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 |
| 6 | Test the relay control circuit of the rear fog lamp relay and the indicator control circuit for a short to voltage or an open. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
| 7 | Test the relay control circuit of the rear fog lamp relay and the indicator control circuit for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
| 8 | Inspect for poor connections at the rear fog lamp relay. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. 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 BCM. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
| 10 | Repair the battery positive voltage circuit of the rear fog lamp relay. Refer to WIRING REPAIRS in Wiring Systems. Did you complete the repair? | Go to Step 13 | |
| 11 | Replace the rear fog lamp relay. Refer to Fog Lamp Relay Replacement (RPO T96) Fog Lamp Relay Replacement (RPO T79) . Did you complete the replacement? | Go to Step 13 | |
| 12 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 13 | |
| 13 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2540
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step test determines if the problem exists in the wiring or the BCM.
- 3: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Exterior Lights Schematics | |||
| 1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Test the following circuits as indicated. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. The backup lamp voltage supply circuit for an open, high resistance, short to voltage or short to ground. The backup lamp ground circuit for an open or high resistance. Did you find and correct the condition? | Go to Step 4 | Go to Step 3 |
| 3 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 4 | |
| 4 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2550
The numbers below refer to the step numbers on the diagnostic table.
- 3: Tests for voltage at the voltage supply side of the low beam headlamp driver module.
- 4: Verifies that the body control module (BCM) is providing PWM ground to the low beam headlamp driver module.
- 5: Tests if ground is constantly being applied to the low beam headlamp driver module.
- 6: Tests if there is opposing voltage present or an open low beam headlamp driver module control circuit.
- 12: 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 | |||
| 1 | Did you perform the Lighting Systems Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, command the low beams ON and OFF. Does the low beam headlamp driver module turn ON and OFF with each command? | Go to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS in Wiring Systems | Go to Step 3 |
| 3 | Turn OFF the ignition. Disconnect the low beam headlamp driver module. Turn ON the ignition, with the engine OFF. Probe the battery positive voltage circuit of the low beam headlamp driver module with a test lamp that is connected to a good ground. Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 |
| 4 | Connect a test lamp between the control circuit of the low beam headlamp driver module and the battery positive voltage circuit of the low beam headlamp driver module. With a scan tool, command the low beam headlamp driver module ON and OFF. Does the test lamp turn ON and OFF with each command? | Go to Step 8 | Go to Step 5 |
| 5 | Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 |
| 6 | Test the control circuit of the low beam headlamp driver module for a short to voltage or an open. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
| 7 | Test the control circuit of the low beam headlamp driver module for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
| 8 | Inspect for poor connections at the low beam headlamp driver module. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. 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 BCM. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
| 10 | Repair the battery positive voltage circuit of the low beam headlamp driver module. Refer to WIRING REPAIRS in Wiring Systems. Did you complete the repair? | Go to Step 13 | |
| 11 | Replace the low beam headlamp control module. Refer to Headlamp Driver Module (HDM) Relay Replacement . Did you complete the replacement? | Go to Step 13 | |
| 12 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 13 | |
| 13 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2575
The numbers below refer to the step numbers on the diagnostic table.
- 2: Listen for an audible click when the high beam relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
- 3: Tests for voltage at the coil side of the high beam relay.
- 4: Verifies that the body control module (BCM) is providing ground to the high beam relay.
- 5: Tests if ground is constantly being applied to the high beam relay.
- 6: Tests if there is opposing voltage present or an open high beam relay control circuit.
- 12: 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 | |||
| 1 | Did you perform the Lighting Systems Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, command the high beam relay ON and OFF. Does the high beam relay turn ON and OFF with each command? | Go to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS in Wiring Systems | Go to Step 3 |
| 3 | Turn OFF the ignition. Disconnect the high beam relay. Turn ON the ignition, with the engine OFF. Probe the battery positive voltage circuit of the high beam relay with a test lamp that is connected to a good ground. Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 |
| 4 | Connect a test lamp between the control circuit of the high beam relay and the battery positive voltage circuit of the high beam relay. With a scan tool, command the high beam relay ON and OFF. Does the test lamp turn ON and OFF with each command? | Go to Step 8 | Go to Step 5 |
| 5 | Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 |
| 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 in Wiring Systems. 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 in Wiring Systems. 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 in Wiring Systems. 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 BCM. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. 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 in Wiring Systems. Did you complete the repair? | Go to Step 13 | |
| 11 | Replace the high beam relay. Refer to High Beam Relay Replacement . Did you complete the replacement? | Go to Step 13 | |
| 12 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 13 | |
| 13 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2580
The numbers below refer to the step numbers on the diagnostic table.
- 2: Listen for an audible click when the park lamp relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
- 3: Tests for voltage at the coil side of the park lamp relay.
- 4: Verifies that the body control module (BCM) is providing ground to the park lamp relay.
- 5: Tests if ground is constantly being applied to the park lamp relay.
- 6: Tests if there is opposing voltage present or an open park lamp relay control circuit.
- 12: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Exterior Lights Schematics | |||
| 1 | Did you perform the Lighting Systems Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, command the park lamp relay ON and OFF. Does the park lamp relay turn ON and OFF with each command? | Go to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS in Wiring Systems | Go to Step 3 |
| 3 | Turn OFF the ignition. Disconnect the park lamp relay. Turn ON the ignition, with the engine OFF. Probe the battery positive voltage circuit of the park lamp relay with a test lamp that is connected to a good ground. Does the test lamp illuminate? | Go to Step 4 | Go to Step 10 |
| 4 | Connect a test lamp between the control circuit of the park lamp relay and the battery positive voltage circuit of the park lamp relay. With a scan tool, command the park lamp relay ON and OFF. Does the test lamp turn ON and OFF with each command? | Go to Step 8 | Go to Step 5 |
| 5 | Does the test lamp remain illuminated with each command? | Go to Step 7 | Go to Step 6 |
| 6 | Test the control circuit of the park lamp relay for a short to voltage or an open. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
| 7 | Test the control circuit of the park lamp relay for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 |
| 8 | Inspect for poor connections at the park lamp relay. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. 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 BCM. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
| 10 | Repair the battery positive voltage circuit of the park lamp relay. Refer to WIRING REPAIRS in Wiring Systems. Did you complete the repair? | Go to Step 13 | |
| 11 | Replace the park lamp relay. Refer to Park Lamp Relay Replacement . Did you complete the replacement? | Go to Step 13 | |
| 12 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 13 | |
| 13 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2585
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step test determines by process of elimination which, if any, dimmable component is causing the DTC to set.
- 3: This step test determines if the problem exists in the wiring or the BCM.
- 5: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Interior Lights Dimming Schematics | |||
| 1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Clear the DTC B2610 with the scan tool. Turn the park lamps ON. Adjust the IP dimmer switch to a mid range dimming position. Disconnect each dimmable component from the instrument panel lamps dimming control circuit, one at a time, while monitoring the scan tool current codes. Does DTC B2610 not reset after a particular dimmable component was disconnected? | Go to Step 4 | Go to Step 3 |
| 3 | Test the instrument panel lamps dimming control circuit for an open, high resistance, short to voltage or short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 6 | Go to Step 5 |
| 4 | Replace the dimmable component associated with when the code did not reset. Refer to the proper replacement procedure for that particular component. Did you complete the repair? | Go to Step 6 | |
| 5 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 6 | |
| 6 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2610
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step test determines if the problem exists in the wiring.
- 3: This step test determines if an open exists in the body wiring harness extension harness.
- 7: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Interior Lights Schematics | |||
| 1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Test the courtesy lamps supply voltage circuit for an open, high resistance, short to voltage, or short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 8 | Go to Step 3 |
| 3 | Test the TBC 3 battery positive supply voltage circuit within the body wiring harness extension harness for continuity. Refer to CIRCUIT TESTING in Wiring Systems. Is continuity present? | Go to Step 4 | Go to Step 5 |
| 4 | Inspect for poor connections at the harness connectors of the BCM. Refer to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS and CONNECTOR REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 8 | Go to Step 7 |
| 5 | Inspect for poor connections at the body wiring harness extension harness connectors. Refer to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS and CONNECTOR REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 8 | Go to Step 6 |
| 6 | Replace the body wiring harness extension harness to the BCM. Refer to BODY WIRING HARNESS EXTENSION REPLACEMENT - BCM in Body Control System. Did you complete the replacement? | Go to Step 8 | |
| 7 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 8 | |
| 8 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2615
The numbers below refer to the step numbers on the diagnostic table.
- 3: Tests for the proper operation of the circuit in the low voltage range.
- 4: Tests for the proper operation of the circuit in the high voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to ground.
- 5: Tests for a short to voltage in the 5 volt reference circuit.
- 6: Tests for a high resistance or an open in the low reference circuit.
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Interior Lights Dimming Schematics | ||||
| 1 | Did you perform the Lighting Systems Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems | |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. With the scan tool, observe the Dimming Input data parameter in the Body Control Module Data List. Does the scan tool indicate that the Dimming Input data parameter is within the specified range? | 4.5 V - 5.5 V | Go to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS in Wiring Systems | Go to Step 3 |
| 3 | Turn OFF the ignition. Disconnect the headlamp switch. Turn ON the ignition, with the engine OFF. With a scan tool, observe the Dimming Input data parameter. Does the scan tool indicate that the Dimming Input data parameter is less than the specified value? | 4.5 V | Go to Step 4 | Go to Step 10 |
| 4 | Turn OFF the ignition. Connect a 3 amp fused jumper wire between the 5 volt reference circuit of the IP dimmer/headlamp switch and the signal circuit of the IP dimmer/headlamp switch. Turn ON the ignition, with the engine OFF. With a scan tool, observe the Dimming Input data parameter. Does the scan tool indicate that the Dimming Input data parameter is greater than the specified value? | 4.86 V | Go to Step 5 | Go to Step 8 |
| 5 | Disconnect the fused jumper wire. Measure the voltage between the 5 volt reference circuit of the IP dimmer/headlamp switch and the low reference circuit of the IP dimmer/headlamp switch. Does the voltage measure less than the specified value? | 5.15 V | Go to Step 6 | Go to Step 7 |
| 6 | Turn OFF the ignition. Disconnect the negative battery cable. Measure the resistance from the low reference circuit of the IP dimmer/headlamp switch to a good ground. Does the resistance measure less than the specified value? | 5 ohms | Go to Step 12 | Go to Step 11 |
| 7 | Test the 5 volt reference circuit of the IP dimmer/headlamp switch for a short to voltage. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 16 | Go to Step 13 | |
| 8 | Test the 5 volt reference circuit of the IP dimmer/headlamp switch for a short to ground, a high resistance, or an open. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 16 | Go to Step 9 | |
| 9 | Test the signal circuit of the IP dimmer/headlamp switch for a short to ground, a high resistance, or an open. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 16 | Go to Step 13 | |
| 10 | Test the signal circuit of the IP dimmer/headlamp switch for a short to voltage. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 16 | Go to Step 13 | |
| 11 | Disconnect the body control module. Test the low reference circuit of the IP dimmer/headlamp switch for a high resistance or an open. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 16 | Go to Step 13 | |
| 12 | Inspect for poor connections at the harness connector of the IP dimmer/headlamp switch. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 16 | Go to Step 14 | |
| 13 | Inspect for poor connections at the harness connector of the body control module. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 16 | Go to Step 15 | |
| 14 | Replace the headlamp switch. Refer to Headlamp Switch Replacement . Did you complete the replacement? | Go to Step 16 | ||
| 15 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 16 | ||
| 16 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK | |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2620
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step test determines if the problem exists in the wiring or the BCM.
- 3: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Interior Lights Dimming Schematics | |||
| 1 | Did you perform the Lighting System Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems |
| 2 | Test the instrument panel lamps dimming control circuit for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 4 | Go to Step 3 |
| 3 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 4 | |
| 4 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2625
The numbers below refer to the step numbers on the diagnostic table.
- 2: Verifies that the value displayed is within the specified range.
- 3: Tests for the proper operation of the circuit in the high voltage range.
- 4: Tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to voltage.
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Headlights/Daytime Running Lights (DRL) Schematics | ||||
| 1 | Did you perform the Lighting Systems Diagnostic System Check? | Go to Step 2 | Go to Diagnostic System Check - Lighting Systems | |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, observe the ambient light sensor parameter in the Body Control Module (BCM) data list. Does the scan tool indicate that the ambient light sensor parameter is within the specified range? | 1.75 - 4.9 V | Go to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS in Wiring Systems | Go to Step 3 |
| 3 | Turn OFF the ignition. Disconnect the ambient light sensor. Turn ON the ignition, with the engine OFF. With a scan tool, observe the ambient light sensor parameter. Does the scan tool indicate that the ambient light sensor parameter is greater than the specified value? | 4.9 V | Go to Step 4 | Go to Step 5 |
| 4 | Turn OFF the ignition. Connect a 3 amp fused jumper wire between the ambient light sensor low reference circuit and the ambient light sensor signal circuit at the ambient light sensor harness connector. Turn ON the ignition, with the engine OFF. With a scan tool, observe the ambient light sensor parameter. Does the scan tool indicate that the ambient light sensor parameter is less than the specified value? | 1.75 V | Go to Step 6 | Go to Step 7 |
| 5 | Test the ambient light sensor signal circuit for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 10 | |
| 6 | Test the ambient light sensor low reference circuit for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 9 | |
| 7 | Test the ambient light sensor signal circuit for a short to voltage, a high resistance, or an open. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 8 | |
| 8 | Test the ambient light sensor low reference circuit for a short to voltage, a high resistance, or an open. Refer to CIRCUIT TESTING and WIRING REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 10 | |
| 9 | Inspect for poor connections at the harness connector of the ambient light sensor. Refer to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS and CONNECTOR REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 11 | |
| 10 | Inspect for poor connections at the harness connector of the BCM. Refer to TESTING FOR INTERMITTENT CONDITIONS AND POOR CONNECTIONS and CONNECTOR REPAIRS in Wiring Systems. Did you find and correct the condition? | Go to Step 13 | Go to Step 12 | |
| 11 | Replace the ambient light sensor. Refer to Ambient Light Sensor Replacement . Did you complete the replacement? | Go to Step 13 | ||
| 12 | IMPORTANT: Perform the setup procedure for the BCM. Replace the body control module (BCM). Refer to BODY CONTROL MODULE REPLACEMENT in Body Control System.Did you complete the replacement? | Go to Step 13 | ||
| 13 | Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset? | Go to Step 2 | System OK | |
| IMPORTANT |
|---|
| Perform the setup procedure for the BCM. |
DTC B2645