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For 1990-2009 cars only

Power Door Locks Inoperative - Front w/AN3

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

I/P Fuse Block B+

3

3

--

--

Driver Door Latch Control

1

1

1

--

Passenger Door Latch Control

2

2

2

--

Rear Doors Unlock Control

B3130 00

B3130 00

B3130 00

--

Rear Doors Lock Control

B3135 00

B3135 00

--

--

Driver Door Switch Ground

--

U0199 00

1

--

Passenger Door Switch Ground

--

U0200 00

2

--

I/P Fuse Block Ground

--

3

3

--

1. Driver Door Lock Malfunction

2. Passenger Door Lock Malfunction

3. Rear Door Lock Malfunction

Circuit/System Description

The driver and passenger door lock and side window switches are integrated control module switch assemblies. The DDS and PDS door lock switches are normally open, 2 position rocker type switches, with detents for lock and unlock. The DDS and PDS are directly connected to the respective door lock actuator through the door lock actuator control circuits. When a door lock or unlock function is activated from the DDS or PDS, a serial data message lock or unlock command is sent to the other door switch and body control module.

Reference Information

Schematic Reference

Door Lock/Indicator Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Door Locks Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, command the front doors to LOCK and UNLOCK by using the driver and passenger door lock switches, each door should perform LOCK and UNLOCK function from each switch.

If the driver door does not LOCK or UNLOCK, refer to Driver Door Lock Malfunction.
If the passenger door does not LOCK or UNLOCK, refer to Passenger Door Lock Malfunction.

Circuit/System Testing

Driver Door Lock Malfunction

  1. Ignition OFF, disconnect the X1 harness connector at the DDS.
  2. Test for less than 1 ohm between the ground circuit terminal 6 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the B+ circuit listed below and ground.
  5. • B+ circuit terminal 2
    • B+ circuit terminal 4
    If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  6. Ignition OFF, connect the X1 harness connector at the DDS and disconnect the harness connector at the driver door latch.
  7. Test for less than 2 ohms between the control circuit terminal 3 and ground.
  8. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the DDS.
  9. Test for less than 2 ohms between the control circuit terminal 2 and ground.
  10. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the DDS.
  11. Ignition ON, connect a test lamp between the control circuit terminal 3 and control circuit terminal 2.
  12. Command the door to LOCK and UNLOCK by using the driver door lock switch. The test lamp should briefly illuminate when commanding the LOCK and UNLOCK states.
  13. If the test lamp is always OFF during either of the commands, test either control circuit for a short to ground. If the circuits test normal, replace the DDS.
  14. If the circuits test normal, test or replace the driver door latch.

Passenger Door Lock Malfunction

  1. Ignition OFF, disconnect the X1 harness connector at the PDS.
  2. Test for less than 1 ohm between the ground circuit terminal 6 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the B+ circuit listed below and ground.
  5. • B+ circuit terminal 2
    • B+ circuit terminal 4
    If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  6. Ignition OFF, connect the X1 harness connector at the PDS and disconnect the harness connector at the passenger door latch.
  7. Test for less than 2 ohms between the control circuit terminal 5 and ground.
  8. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the PDS.
  9. Test for less than 2 ohms between the control circuit terminal 6 and ground.
  10. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the PDS.
  11. Ignition ON, connect a test lamp between the control circuit terminal 5 and control circuit terminal 6.
  12. Command the door to LOCK and UNLOCK by using the passenger door lock switch. The test lamp should briefly illuminate when commanding the LOCK and UNLOCK states.
  13. If the test lamp is always OFF during either of the commands, test either control circuit for a short to ground. If the circuits test normal, replace the PDS.
  14. If the circuits test normal, test or replace the passenger door latch.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the appropriate door latch.
  2. Install a 15A fused jumper wire between the control terminal listed below and 12 volts:
  3. • Driver door latch control terminal 2
    • Passenger door latch control terminal 5
  4. Momentarily install a jumper wire between the control terminal listed below and ground. The door latch should perform the LOCK or UNLOCK function.
  5. • Driver door latch control terminal 3
    • Passenger door latch control terminal 6
    If the function does not perform as specified, replace the door latch.
  6. Reverse the jumper wires; the door latch should perform the UNLOCK or LOCK function.
  7. If the function does not perform as specified, replace the door latch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Front Side Door Lock Replacement
    •  Control Module References for DDS or PDS replacement, programming, and setup

Power Door Locks Inoperative - Front w/o AN3

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

The power door locks are controlled by the body control module (BCM) through lock and unlock printed circuit board relays in the IP fuse block. The driver and passenger door lock switches are normally open, 2 position rocker type switches, with detents for lock and unlock. The lock and unlock switch signal circuits are referenced from battery voltage by the BCM and when a door lock or unlock switch is pressed the signal circuit is closed to ground through the switch contacts and BCM determines the signal is active. The unlock relays are controlled by the BCM through driver door and passenger door low side drive control circuits and the lock relays are controlled through a single high side drive control circuit. During lock or unlock operation, battery voltage will be supplied to the lock actuators through the energized relays and grounded through the de-energized relays.

Reference Information

Schematic Reference

Door Lock/Indicator Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Power Door Locks Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for Scan Tool Information

Circuit/System Verification

  1. Verify that the BCM door lock switch parameters display Idle, Lock, and Unlock while operating the driver and passenger door lock switches to lock and unlock.
  2. If either of the scan tool parameters do not match the actual switch positions perform the Door Lock Switch Circuit Test.
  3. Verify that a test lamp connected to ground illuminates on the supply side of the lock fuses 1 and 2 when a lock switch is activated.
  4. If the test lamp does not illuminate at one or both fuses perform the Door Lock Relay Control Circuit Test.
    If the test lamp illuminates at both fuses perform the Door Lock Actuator Circuit Test.
  5. Verify that a test lamp connected to ground illuminates on the supply side of the unlock DRV fuse when an unlock switch is activated.
  6. If the test lamp does not illuminate at any of the fuses perform the Driver Door Unlock Relay Control Circuit Test.
    If the test lamp illuminates perform the Door Lock Actuator Circuit Test.
  7. Verify that a test lamp connected to ground illuminates on the supply side of the unlock fuses 1 and 2 when a unlock switch is activated.
  8. If the test lamp does not illuminate at one or both fuses perform the Door Lock Relay Control Circuit Test.
    If the test lamp illuminates at both fuses perform the Door Lock Actuator Circuit Test.

Circuit/System Testing

Door Lock Switch Circuit Test

  1. Disconnect the affected door lock switch and verify that the scan tool switch parameter displays Idle.
  2. If the parameter displayed is Lock or Unlock test the affected switch signal circuit for a short to ground. If the circuit tests normal replace the BCM.
  3. Verify less than 1 ohm or resistance from the ground circuit terminal B to ground.
  4. If the resistance is greater than the specified value repair the ground circuit for an open/high resistance.
  5. Connect a fused jumper wire from the lock switch signal circuit terminal D to ground and verify that the scan tool switch parameter displays Lock.
  6. If the parameter displayed is not Lock test the lock switch signal circuit for an open/high resistance. If the circuit tests normal replace the BCM.
  7. Connect a fused jumper wire from the unlock switch signal circuit terminal E to ground and verify that the scan tool switch parameter displays Unlock.
  8. If the parameter displayed is not Unlock test the unlock switch signal circuit for an open/high resistance. If the circuit tests normal replace the BCM.
  9. If the circuits test normal replace the affected door lock switch.

Door Lock Relay Control Circuit Test

  1. Verify that a test lamp connected to battery voltage illuminates when connected to the supply side of the lock 1 and 2 fuses in the IP fuse block.
  2. If the test lamp does not illuminate test the lock/unlock relay ground circuit for an open/high resistance. If the circuit tests normal replace the IP fuse block.
  3. Disconnect the BCM connector X7.
  4. Verify that all of the door lock actuators lock when a fused jumper wire is connected to the door lock relay control circuit terminal 7 and briefly applied to battery voltage.
  5. If all of the door lock actuators do not lock, test the door lock relay control circuit for an open/high resistance. If the circuit tests normal replace the IP fuse block.
    If only the front or rear door lock actuators do not lock replace the IP fuse block.
  6. If the circuits test normal replace the BCM.

Driver Door Unlock Relay Control Circuit Test

  1. Verify that a test lamp connected to battery voltage illuminates when connected to the supply side of the DRV unlock fuse in the IP fuse block.
  2. If the test lamp does not illuminate test the IP fuse block ground circuit for an open/high resistance. If the circuit tests normal replace the IP fuse block.
  3. Disconnect the BCM connector X7.
  4. Verify that the driver door lock actuator unlocks when a fused jumper wire is connected to the driver door unlock relay control circuit terminal 6 and briefly applied to ground.
  5. If the driver door lock actuator does not unlock, test the driver door unlock relay control circuit for an open/high resistance. If the circuit tests normal replace the IP fuse block.
  6. If the circuits test normal replace the BCM.

Passenger Door Unlock Relay Control Circuit Test

  1. Verify that a test lamp connected to battery voltage illuminates when connected to the supply side of the unlock 1 and 2 fuses in the IP fuse block.
  2. If the test lamp does not illuminate test the IP fuse block ground circuit for an open/high resistance. If the circuit tests normal replace the IP fuse block.
  3. Disconnect the BCM connector X7.
  4. Verify that all of the passenger door lock actuators unlock when a fused jumper wire is connected to the passenger door unlock relay control circuit terminal 9 and briefly applied to ground.
  5. If the passenger door lock actuators do not unlock, test the passenger door unlock relay control circuit for an open/high resistance. If the circuit tests normal replace the IP fuse block.
  6. If the circuits test normal replace the BCM.

Door Lock Actuator Circuit Test

  1. Disconnect the affected door latch connector and connect a test lamp across the lock actuator control circuit terminals.
  2. Verify that the test lamp illuminates briefly when a lock and unlock switch is activated.
  3. If the test lamp does not illuminate in both switch positions test the lock actuator control circuits for an open/high resistance or short to ground. If the circuits test normal replace the IP fuse block.
  4. If the circuits test normal replace the affected door latch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Front Side Door Lock Replacement
    •  Rear Door Lock Replacement
    •  Instrument Panel Electrical Center or Junction Block Replacement - Left Side
    •  Control Module References for BCM replacement, programming, and setup