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For 1990-2009 cars only
Makes 🢒 HUMMER 🢒 2009 🢒 H2 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Midgate Latch 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

Midgate Latch Switch Signal

2

2

--

--

Midgate Latch Control

1

1

1

--

Midgate Latch Switch Ground

--

2

--

--

Midgate Latch Ground

--

1

--

--

1. Midgate latch malfunction

2. Midgate latch switch malfunction

Circuit/System Description

The midgate latch release switches are a single input to the midgate window motor. The latch release switch signal circuit is referenced from battery voltage from the midgate window motor. When a latch release switch is pressed, the switch contacts close the signal circuit to ground. When the midgate window motor receives an active release switch signal, battery voltage is applied to the midgate latches through the midgate latch control circuit.

Diagnostic Aids

Before testing can be performed, the midgate must be opened. Refer to Opening the Midgate Without Electrical Power for the appropriate procedure.

Reference Information

Schematic Reference

Release Systems Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Midgate Description and Operation

Electrical Information Reference

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

Circuit/System Verification

Ignition ON, midgate window down, command the midgate to UNLATCH by using the left and right midgate latch switches. The midgate should perform the UNLATCH function from both switches.

⇒If the left or right midgate latch switch is inoperative, refer to Midgate Latch Switch Malfunction.
⇒If one side of the midgate does not UNLATCH, refer to Midgate Latch Malfunction.
⇒If the midgate latch is inoperative from both midgate latch switches, refer to Midgate Release Inoperative.

Circuit/System Testing

Midgate Latch Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate midgate latch switch.
  2. Test for less than 1 ohm between the ground circuit terminal B and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, test for greater than 9 volts between the signal circuit terminal A and ground.
    4. ⇒If less than the specified range, test the signal circuit for an open/high resistance.
  4. If all circuits test normal, test or replace the midgate latch switch.

Midgate Latch Malfunction

  1. Ignition OFF, disconnect the harness connector at the appropriate midgate latch.
  2. Test for less than 5 ohms between the ground circuit terminal E and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Connect a test lamp between the control circuit terminal D and ground.
  4. Ignition ON, command the midgate to UNLATCH by pressing the midgate latch switch, the test lamp should illuminate during the UNLATCH command.
    5. ⇒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 midgate latch.

Midgate Release Inoperative

  1. Ignition OFF, disconnect the harness connector at the midgate window motor.
  2. Connect a test lamp between the signal circuit terminal 5 and B+.
  3. Observe the function of the test lamp while pressing the left and right midgate latch switches. The test lamp should illuminate with each press of the switch.
    4. ⇒If the test lamp is always OFF, test the signal circuit for a short to voltage or an open/high resistance.
    ⇒If the test lamp is always ON, test the signal circuit for a short to ground. If the circuit tests normal, test or replace the appropriate midgate latch switch.
  4. Verify that a test lamp does not illuminate between the control circuit terminal 4 and ground.
    5. ⇒If a test lamp illuminates, test the control circuit for a short to voltage.
  5. Momentarily install a 25A fused jumper wire between the control circuit terminal 4 and B+. Verify both midgate latches activate.
    6. ⇒If both midgate latches are inoperative, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the appropriate midgate latch.
  6. If all circuits test normal, replace the midgate window motor.

Component Testing

Midgate Latch Switch

  1. Ignition OFF, disconnect the harness connector at the appropriate midgate latch switch.
  2. Test for infinite resistance between the signal terminal A and the ground terminal B with the switch in the open position.
    3. ⇒If less than the specified value, replace the midgate latch switch.
  3. Test for less than 2 ohms between the signal terminal A and the ground terminal B with the switch in the closed position.
    4. ⇒If greater than the specified range, replace the midgate latch switch.

Midgate Latch

  1. Ignition OFF, disconnect the harness connector at the appropriate midgate latch.
  2. Install a 25A fused jumper wire between the control terminal D and 12V. Install a jumper wire between the ground terminal E and ground. Verify the midgate latch activates.
    3. ⇒If the latch does not perform as specified, replace the midgate latch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Midgate Latch Replacement
    •  Midgate Latch Switch Replacement
    •  Midgate Window Regulator Module Motor Replacement