Midgate Ajar Indicator Malfunction

Midgate Ajar Indicator Malfunction

Diagnostic Instructions

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



Circuit/System Description

The latch ajar switches provide a single input to the midgate control module. The switch signal circuit is supplied accessory voltage through a resistor and monitored by the midgate control module. When the midgate is opened both of the latch ajar switches close and the circuit is pulled low. The midgate control module provides an ajar signal to the body control module through the midgate ajar indicator signal circuit. The body control module supplies the signal circuit with accessory voltage through a resistor and monitors the voltage level. When the midgate is ajar the midgate control module will ground the ajar indicator signal circuit and the voltage monitored by the body control module will drop indicating the circuit is active.


Reference Information
Schematic Reference

Release Systems Schematics (Release Systems Schematics)
Connector End View Reference

Component Connector End Views (Component Connector End Views)
Description and Operation

Midgate Description and Operation ()
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Programming and Relearning (Programming and Relearning)for Scan Tool Information


Circuit/System Verification

1. Ignition ON, with the midgate fully closed, verify the scan tool rear closure ajar switch parameter is inactive.

• If the rear closure ajar switch parameter is active, refer to the Midgate Ajar Switch Circuit Test.

2. With the midgate open, verify the rear closure ajar switch parameter is active.

• If the rear closure ajar switch parameter is inactive, refer to the Midgate Ajar Switch Circuit Test.

3. If the liftgate ajar switch input to the BCM functions normally replace the IPC.



Circuit/System Testing


Midgate Ajar Switch Circuit Test
1. Ignition OFF, disconnect the harness connector at the midgate module.
2. Ignition ON, verify the scan tool rear closure ajar switch parameter is inactive.

• If not the specified value, test the signal circuit terminal 12 for a short to ground. If the circuit tests normal, replace the BCM.

3. Install a 3A fused jumper wire between the signal circuit terminals 12 and ground. Verify the scan tool rear closure ajar switch parameter is active.

• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

4. Ignition OFF, connect the harness connector at the midgate module.
5. Disconnect the harness connector at the right midgate latch.
6. Test for less than 1.0 ohm of resistance between the ground circuit terminal B and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

7. Disconnect the harness connector at the left midgate latch.
8. Ignition ON, verify the scan tool rear closure ajar switch parameter is active.

• If not the specified value, test the signal circuit terminal B for a short to ground. If the circuit tests normal, replace the midgate control module.

9. Install a 3A fused jumper wire between the signal circuit terminal B and ground. Verify the scan tool rear closure ajar switch parameter is inactive.

• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the midgate control module.

10. Connect the harness connector at the left midgate latch.
11. Install a 3A fused jumper wire between the signal circuit terminal A at the right midgate latch and ground. Verify the scan tool rear closure ajar switch parameter is inactive.

• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the left midgate latch.

12. If all circuits test normal, test or replace the right midgate latch.



Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Midgate Latch Replacement ()
* Programming and Relearning (Programming and Relearning)for BCM or IPC replacement, programming, and setup.


Programming and Relearning (Programming and Relearning)for BCM or IPC replacement, programming, and setup.