For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Door Lock/Indicator Schematics Connector End View Reference: Power Door Systems Connector End Views DEFINITION: This diagnostic table is for problems with passenger door locks only or all door locks on vehicles without keyless entry. Ignore the driver door lock when using this table on vehicles with keyless entry.
1 | Did you perform the Diagnostic System Check for the door systems? | Go to Step 2 | Go to Diagnostic System Check - Door Systems
2 | Verify that the power door locks inoperative - passenger door fault is present. Does the system operate normally? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3
3 |

1. Connect a scan tool.
2. Turn ON the ignition, with the engine OFF.
3. Close all the doors.
4. Using the scan tool, observe the Door Lock Switch input into the BCM.

Does the scan tool display Idle?

Go to Step 5

Go to Step 4

4 | Test the door lock lock/unlock signal circuit into the 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 29 | Go to Step 24
5 |

1. With the scan tool, observe the Door Lock Switch input while performing the next two actions.
2. Press the driver door lock switch to lock and then to unlock.
3. Press the passenger door lock switch to lock and then to unlock.

Does the scan tool display Lock for the lock conditions and Unlock for the unlock conditions from both switches?

Go to Step 6

Go to Step 7

6 |

1. Place all of the door lock knobs in the unlock position by hand.
2. Command the door locks to lock from any door lock switch.
3. Place all the door lock knobs in the lock position by hand.
4. Command the door locks to unlock from any door lock switch.

Did any of the door locks lock or unlock?

Go to Step 10

Go to Step 11

7 | Using a test lamp connected to battery positive voltage, probe the ground circuit to each unresponsive door lock switch. Does the test lamp illuminate? | Go to Step 8 | Go to Step 24
8 |

1. Using a fused jumper connected to a good ground, probe the door lock lock/unlock signal circuit at each door lock switch harness connector.
2. Observe the scan tool.

Does the scan tool display lock in each case?

Go to Step 24

Go to Step 9

9 | Test the door lock lock/unlock signal circuit for an open or high resistance. Did you find and correct the condition? | Go to Step 29 | Go to Step 21
10 |

1. Remove the door lock relay and the door unlock relay.
2. With a test lamp connected to ground, probe the door lock control circuit at the door lock relay socket.
3. Observe the test lamp while commanding the door locks to lock with any door lock switch.
4. With a test lamp connected to ground, probe the door unlock control circuit at the door unlock relay socket.
5. Observe the test lamp while commanding the door locks to unlock with any door lock switch.
6. Reinstall both relays.

Did the test lamp illuminate for each circuit when commanded to lock or unlock?

Go to Step 16

Go to Step 20

11 | Test the door lock relay battery positive voltage circuit for 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 29 | Go to Step 12
12 | Test the door lock relay battery positive 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 29 | Go to Step 13
13 | Test the door lock relay and the door unlock relay ground circuits for 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 29 | Go to Step 14
14 | Test both door lock and unlock control circuits between the BCM and relays 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 29 | Go to Step 15
15 | Test both door lock actuator lock and unlock control circuits between the relays and lock actuators 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 29 | Go to Step 16
16 |

1. With a test lamp connected to ground, probe the door lock actuator lock control circuit at an inoperative actuator.
2. While observing the test lamp, command the door locks to lock from either door lock switch.

Did the test lamp illuminate?

Go to Step 17

Go to Step 23

17 |

1. With a test lamp connected to ground, probe the door lock actuator unlock control circuit at an inoperative actuator.
2. While observing the test lamp, command the door locks to unlock from either door lock switch.

Did the test lamp illuminate?

Go to Step 18

Go to Step 23

18 | Did the test lamp stay illuminated for either of the door lock actuator lock or unlock control circuits even without commanding the door locks to do anything? | Go to Step 27 | Go to Step 19
19 | Test the door lock actuator lock and unlock control circuits for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 29 | Go to Step 22
20 |

1. Test the inoperative door lock control circuit for an open.
2. Test the inoperative door unlock control circuit for an open.

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 29

Go to Step 21

21 | Inspect for poor connections at the BCM harness connector. 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 29 | Go to Step 25
22 | Inspect for poor connections at the door lock actuator harness connector. 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 29 | Go to Step 26
23 | Inspect for poor connections at the door lock relays. 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 29 | Go to Step 27
24 | Inspect for poor connections at the door lock switch harness connector. 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 29 | Go to Step 28
25 | Important: Perform the set up procedure for the BCM. Replace the BCM. Refer to Body Control Module Replacement in Body Control Systems. Did you complete the repair? | Go to Step 29 | --
26 | Replace the inoperative door lock actuator. Refer to Front Side Door Lock Actuator Replacement or Rear Side Door Lock Actuator Replacement . Did you complete the repair? | Go to Step 29 | --
27 | Replace the inoperative door lock or unlock relay. Did you complete the repair? | Go to Step 29 | --
28 | Replace the inoperative door lock switch. Refer to Door Lock Switch Replacement . Did you complete the repair? | Go to Step 29 | --
29 |

1. If necessary, replace the DOOR LOCK 15A fuse.
2. Use the scan tool in order to clear the DTCs.
3. Operate the system in order to verify the repair.

Did you find and correct the condition?

System OK

Go to Step 3