For a full page schematic, refer to Door Lock/Indicator Schematics .
The body control module (BCM) monitors and supplies an output voltage on CKT 195 to LOCK the doors. When the BCM receives a lock signal from a door lock switch the BCM supplies voltage to the lock relay to LOCK the doors.
• | The system voltage must be between 9.0 and 16.0 volts. |
• | The door lock switch must be activated to LOCK/UNLOCK the doors. |
• | When CKT 195 is shorted to battery voltage for approximately 3 minutes. |
• | The system voltage must be between 9.0-16.0 volts. |
The power door lock system will not function with either power door lock switch.
• | A current DTC will clear immediately after the short to battery voltage is corrected. |
• | A history DTC will clear after 100 consecutive ignition cycles without a fault present. |
• | History and current DTC(s) can be cleared using a scan tool. |
• | Always begin diagnosis with the first DTC listed on the scan tool. |
• | The scan tool must display DTC B3138 as a current code before performing these diagnostics. |
• | Perform a visual inspection for loose or poor connections at all related components |
The number(s) below refer to the step number(s) on the diagnostic table.
Listen for an audible click when the door lock relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
Verifies that the Body Control Module (BCM) is providing voltage to the door lock relay.
Tests for an open in the ground circuit to the door lock relay.
Tests if voltage is constantly being applied to the door lock relay.
After replacement of the BCM you must calibrate the new module for proper operation.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Did you perform the Power Door Systems Diagnostic System Check? | -- | Go to Step 2 | |
Does the door lock 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 turn ON and OFF with each command? | -- | Go to Step 4 | Go to Step 5 | |
Does the test lamp turn ON and OFF with each command? | -- | Go to Step 8 | Go to Step 10 | |
Does the test lamp remain illuminated with each command? | -- | Go to Step 7 | Go to Step 6 | |
6 | Test the control circuit of the door lock 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 |
7 | Test the control circuit of the door lock relay 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 13 | Go to Step 9 |
8 | Inspect for poor connections at the door lock 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 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 ground circuit of the door lock relay . Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 13 | -- |
11 | Replace the door lock relay . Did you complete the replacement? | -- | Go to Step 13 | -- |
Did you complete the replacement? | -- | Go to Step 13 | -- | |
13 |
Does the DTC reset? | -- | Go to Step 2 | System OK |