GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 Express - AWD 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Access Panel Release Inoperative

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

Access Panel Relay B+

1, 2

1, 2

--

--

Access Panel Right Side Relay Control

1

1

1

--

Access Panel Left Side Front Relay Control

1

1

1

--

Access Panel Left Side Rear Relay Control

1

1

1

--

Access Panel Actuator Control

2

2

2

--

Access Panel Actuator Ground

--

2

2

--

1. Access Panel Release System Malfunction

2. Access Panel Actuator Malfunction

Circuit/System Description

The access panel release system consists of three relays and six actuators. When the body control module (BCM) receives a command to release the appropriate access panel, it enables the access panel release system by supplying a ground to the access panel relay coil. With the relay energized, battery positive voltage is allowed from the relay switched input through the switch contacts and out the relay switched output to the access panel actuator releasing the access panel.

Reference Information

Schematic Reference

Release Systems Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Access Panel 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. Ignition ON, command the appropriate access panel to release with a scan tool. The access panel actuators should release the access panel.
    2. ⇒If the right access panel does not release, refer to Right Access Panel Malfunction.
    ⇒If the left front access panel does not release, refer to Left Front Access Panel Malfunction.
    ⇒If the left rear access panel does not release, refer to Left Rear Access Panel Malfunction.
    ⇒If the access panel does not fully release, refer to Access Panel Actuator Malfunction.
  2. Command the access to release by pressing the release button on the key fob. The access panel actuators should release the access panel.
    3. ⇒If the access panel actuators fails to activate, refer to Keyless Entry System Inoperative .

Circuit/System Testing

Right Access Panel Malfunction

  1. Ignition OFF, disconnect the Right Access Panel relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 12 and ground.
    3. ⇒If the test lamp illuminates, test the control circuit for a short to voltage.
  3. Verify that a test lamp illuminates between the B+ circuit terminal 15 and ground.
    4. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Verify that a test lamp illuminates between the B+ circuit terminal 11 and ground.
    5. ⇒If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
  5. Connect a 15A fused jumper wire between the B+ circuit terminal 11 and the control circuit terminal 12. Verify that both actuators are activated.
    6. ⇒If the actuators do not activate, test the control circuit for an short to ground or an open/high resistance. If the circuit tests normal, test or replace the actuators.
  6. Connect a test lamp between the B+ circuit terminal 15 and the control circuit terminal 13.
  7. Command the Right Side Rear Access Panel ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    8. ⇒If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
    ⇒If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  8. If all circuits test normal, test or replace the Right Access Panel relay.

Left Front Access Panel Malfunction

  1. Ignition OFF, disconnect the Left Front Access Panel relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 2 and ground.
    3. ⇒If the test lamp illuminates, test the control circuit for a short to voltage.
  3. Verify that a test lamp illuminates between the B+ circuit terminal 5 and ground.
    4. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance
  4. Verify that a test lamp illuminates between the B+ circuit terminal 1 and ground.
    5. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  5. Connect a 15A fused jumper wire between the B+ circuit terminal 1 and the control circuit terminal 2. Verify that both actuators are activated.
    6. ⇒If the actuators do not activate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the actuators.
  6. Connect a test lamp between the B+ circuit terminal 5 and the control circuit terminal 3.
  7. Command the Left From Access Panel ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    8. ⇒If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
    ⇒If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  8. If all circuits test normal, test or replace the Left Front Access Panel relay.

Left Rear Access Panel Malfunction

  1. Ignition OFF, disconnect the Left Rear Access Panel relay.
  2. Ignition ON, verify that a test lamp does not illuminate between the control circuit terminal 7 and ground.
    3. ⇒If the test lamp illuminates, test the control circuit for a short to voltage.
  3. Verify that a test lamp illuminates between the B+ circuit terminal 10 and ground.
    4. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Verify that a test lamp illuminates between the B+ circuit terminal 6 and ground.
    5. ⇒If the test lamp does not illuminate, test the B+ circuit for an open/high resistance.
  5. Connect a 15A fused jumper wire between the B+ circuit terminal 6 and the control circuit terminal 7. Verify the both actuators are activated.
    6. ⇒If the actuators do not activate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the actuators.
  6. Connect a test lamp between the B+ circuit terminal 10 and the control circuit terminal 8.
  7. Command the Left Side Rear Access Panel ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    8. ⇒If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
    ⇒If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  8. If all circuits test normal, test or replace the Left Rear Access Panel relay.

Access Panel Actuator Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate access panel actuator.
  2. Test for less than 1 ohm between the ground circuit terminal 4 and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, connect a test lamp between the control circuit terminal 3 and ground.
  4. Command the access panel to release with a scan tool, the test lamp should illuminate during the release command.
    5. ⇒If the test lamp is always ON, test the control circuit for a short to voltage.
    ⇒If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance.
  5. If all circuits test normal, test or replace the access panel release actuator.

Component Testing

Relay Test

  1. Ignition OFF, disconnect the appropriate access panel relay.
  2. Test 60-200 ohms between terminals 85 and 86.
    3. ⇒If the resistance is not within the specified range, replace the relay.
  3. Test for infinite resistance between the following terminals:
    4. • 30 and 86
    • 30 and 87
    • 30 and 85
    • 85 and 87
    ⇒If not the specified value, replace the relay.
  4. Install a 15A fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87.
    5. ⇒If greater than the specified range, replace the relay.

Access Panel Actuator Test

  1. Ignition OFF, disconnect the harness connector at the appropriate access panel actuator.
  2. Ignition ON, install a 15-amp fused jumper wire between the control terminal 3 and 12 volts. Momentarily install a jumper wire between the ground terminal 4 and ground. The access panel actuator should perform the RELEASE function.
    3. ⇒If the function does not perform as specified, replace the access panel actuator.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Relay Replacement
    •  Control Module References for BCM replacement, setup, and programming