Test Description
The numbers below refer to the step numbers on the diagnostic table.
- 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 Schematics Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Inspect the TBC 2C fuse in the instrument panel (I/P) fuse block. Is the fuse open? | Go to Step 3 | Go to Step 4 |
| 3 | Test the inadvertent power supply voltage circuit, and the TBC 2C battery supply voltage to the body control module (BCM) 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 6 | Go to Step 4 |
| 4 | 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 6 | Go to Step 5 |
| 5 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. 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 |
DTC B1480
The numbers below refer to the step numbers on the diagnostic table.
- 3: This step test determines if the problem exists in the wiring or the BCM.
- 4: 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: Exterior Lights Schematics Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Inspect the TBC 2B fuse in the instrument panel fuse block. Is the fuse open? | Go to Step 3 | Go to Step 4 |
| 3 | Test the following circuits for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems: Backup lamp supply voltage Courtesy lamp supply voltage TBC 2B battery positive voltage to the body control module (BCM) Did you find and correct the condition? | Go to Step 6 | Go to Step 5 |
| 4 | Test the backup lamp supply voltage circuit for the following conditions: An open A short to voltage High resistance 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 |
| 5 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. 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 |
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 headlamp low beam relay.
- 4: Verifies that the BCM is providing ground to the headlamp low beam relay.
- 5: Tests if ground is constantly being applied to the headlamp low beam relay.
- 6: Tests if there is opposing voltage present or an open headlamp low beam relay control circuit, including the relay coil side.
- 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 Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Turn ON the ignition, with the engine OFF. Place the headlamp switch in the ON position. Place the headlamp dimmer switch in the low beam position. Place the headlamp switch in the OFF position. Do the low beam headlamps operate as expected? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
| 3 | Turn OFF the ignition. Disconnect the headlamp low beam relay. Turn ON the ignition, with the engine OFF. Connect a test lamp between the control circuit of the headlamp low beam relay and 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 headlamp low beam relay and the battery positive voltage circuit of the headlamp low beam relay. While observing the test lamp, place the headlamp switch in the ON position, and then the OFF position. Does the test lamp turn ON and OFF with each cycle of the switch? | Go to Step 8 | Go to Step 5 |
| 5 | Does the test lamp remain illuminated with each cycle of the switch? | Go to Step 7 | Go to Step 6 |
| 6 | Test the control circuit of the headlamp low 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 headlamp low 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 headlamp low 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 body control module (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 headlamp low beam relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 13 | |
| 11 | Replace the headlamp low beam relay. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems. Did you complete the replacement? | Go to Step 13 | |
| 12 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. 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 |
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 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, including the relay coil side.
- 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 Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Turn ON the ignition, with the engine OFF. Place the headlamp switch in the ON position. Place the headlamp dimmer switch in the high beam position. Place the headlamp switch in the OFF position. Does the high beam headlamps operate as expected? | 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. Connect a test lamp between the control circuit of the headlamp high beam relay and 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. While observing the test lamp, place the headlamp switch in the ON position, and then the OFF position. Does the test lamp turn ON and OFF with each cycle of the switch? | Go to Step 8 | Go to Step 5 |
| 5 | Does the test lamp remain illuminated with each cycle of the switch? | 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 body control module (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 Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems. Did you complete the replacement? | Go to Step 13 | |
| 12 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. 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 |
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: This step tests for voltage at the coil side of the park lamp relay.
- 4: This step verifies that the BCM is providing ground to the park lamp relay.
- 5: This step tests if ground is constantly being applied to the park lamp relay.
- 6: This step 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 Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 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. Connect a test light between the battery positive voltage circuit of the park lamp relay and 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 body control module (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 Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems. Did you complete the replacement? | Go to Step 13 | |
| 12 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. 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 |
DTC B2585
The numbers below refer to the step numbers on the diagnostic table.
- 2: Listen for an audible click when the DRL relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
- 3: This step tests for voltage at the coil side of the DRL relay.
- 4: This step verifies that the BCM is providing ground to the DRL relay.
- 5: This step tests if ground is constantly being applied to the DRL relay.
- 6: This step tests if there is opposing voltage present or an open in the DRL 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 Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, command the DRL relay ON and OFF. Does the daytime running lights (DRL) 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 DRL relay. Turn ON the ignition, with the engine OFF. Connect a test lamp between the battery positive voltage circuit of the DRL relay and 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 and the battery positive voltage circuit of the DRL relay. With a scan tool, command the DRL 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 DRL relay for high resistance, an open, or a short to voltage. 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 DRL 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 DRL relay. 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 |
| 9 | Inspect for poor connections at the harness connector of the body control module (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 |
| 10 | Repair the DRL supply voltage circuit of the DRL relay. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 13 | |
| 11 | Replace the DRL relay. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems. Did you complete the replacement? | Go to Step 13 | |
| 12 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. 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 |
DTC B2600
The numbers below refer to the step numbers on the diagnostic table.
- 5: This step test determines if the problem exists in the headlamp switch or the BCM.
- 10: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Interior Lights Dimming Schematics Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Is the TBC 2 A fuse in the instrument panel fuse block open? | Go to Step 3 | Go to Step 4 |
| 3 | 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 11 | Go to Step 8 |
| 4 | Test the instrument panel lamps dimming supply voltage circuit and 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 11 | Go to Step 5 |
| 5 | Ensure that the headlamp switch is in the on position. Ensure that the instrument panel dimmer switch is the full bright position. With the headlamp switch still connected, connect a test lamp between the instrument panel lamps dimming control circuit and the ground circuit of the headlamp switch connector. Does the test lamp illuminate? | Go to Step 6 | Go to Step 7 |
| 6 | Inspect for poor connections at the harness connector of the headlamp switch. 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 11 | Go to Step 9 |
| 7 | Inspect for poor connections at the harness connector of the body control module (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 11 | Go to Step 10 |
| 8 | Repair the battery positive voltage circuit of the BCM from the TBC 2 A fuse in the instrument panel fuse block. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 11 | |
| 9 | Replace the headlamp and panel dimmer switch. Refer to Headlamp Switch Replacement . Did you complete the replacement? | Go to Step 11 | |
| 10 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 11 | |
| 11 | 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 |
DTC B2610
The numbers below refer to the step numbers on the diagnostic table.
- 3: This step test determines if the problem exists in the wiring or the BCM.
- 4: 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 Schematics Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Inspect the TBC 2B fuse in the instrument panel fuse block. Is the fuse open? | Go to Step 3 | Go to Step 4 |
| 3 | Test the following circuits for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems: Courtesy lamp supply voltage Backup lamp supply voltage TBC 2B battery positive voltage to the body control module (BCM) Did you find and correct the condition? | Go to Step 6 | Go to Step 5 |
| 4 | Test the courtesy lamp supply voltage circuit for the following conditions: An open A short to voltage High resistance 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 |
| 5 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. 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 |
DTC B2615
The numbers below refer to the step numbers on the diagnostic table.
- 3: This step tests for the proper operation of the circuit in the low voltage range.
- 4: This step 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: This step tests for a short to voltage in the 5-volt reference circuit.
- 6: This step tests for a high resistance or an open in the dimming return circuit.
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| Schematic Reference: Interior Lights Dimming Schematics Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | ||||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | |
| 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 (BCM) Data List. Does the scan tool indicate that the Dimming Input data parameter is within the specified range? | 4.5-5.5 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 instrument panel (I/P) dimmer/headlamp switch and the dimming input circuit of the I/P 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 I/P dimmer/headlamp switch and the dimming return circuit of the I/P 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 dimming return circuit of the I/P 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 I/P 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 I/P 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 dimming input circuit of the I/P 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 dimming input circuit of the I/P 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 dimming return circuit of the I/P 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 I/P 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 BCM. 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 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. 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 | |
DTC B2620
The number below refers to the step number on the diagnostic table.
- 4: After replacement of the BCM you must calibrate the new module for proper operation.
| Step | Action | Yes | No |
|---|---|---|---|
| Schematic Reference: Interior Lights Dimming Schematics Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | |||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
| 2 | Test the following circuits for a short to ground: Instrument panel lamps dimming control LED dimming supply Battery positive voltage circuit of body control module (BCM) from the TBC 2 A fuse Did you find and correct the condition? | Go to Step 5 | Go to Step 3 |
| 3 | 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 5 | Go to Step 4 |
| 4 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 5 | |
| 5 | 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 |
DTC B2625
The numbers below refer to the step numbers on the diagnostic table.
- 2: This step verifies that the value displayed is within the specified range.
- 3: This step tests for the proper operation of the circuit in the high voltage range.
- 4: This step 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 Connector End View Reference: Lighting Systems Connector End Views or Computer/Integrating Systems Connector End Views in Computer/Integrating Systems | ||||
| 1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | |
| 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 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. 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 | |
DTC B2645