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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2009 🢒 STS 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Trunk Ajar Indicator Malfunction

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

Trunk Ajar Switch Signal

2

2

2

--

Rear Compartment Lid Release Actuator Ground

--

1, 2

--

--

  1. Trunk Release Inoperative
  2. Trunk Ajar Indicator Malfunction

Circuit/System Description

When the rear compartment lid release actuator releases the rear compartment lid, the rear compartment lid ajar switch, which is internal the rear compartment lid release actuator, is supplied with ground which causes the trunk ajar switch signal circuit to be pulled low. The trunk ajar switch signal circuit is an input to the rear integration module (RIM). When the RIM receives a trunk ajar signal, a serial data message is sent to the instrument panel cluster (IPC) requesting the TRUNK OPEN message be displayed on the message center.

Reference Information

Schematic Reference

Release Systems Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Luggage Compartment 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, observe the scan tool Rear Compartment Lid Ajar parameter while opening and closing the trunk. The parameter should change between Closed and Ajar.

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the rear compartment lid latch.
  2. Ignition ON, verify the scan tool Rear Compartment Lid Ajar parameter is Closed.
    3. ⇒If not the specified value, test the signal circuit terminal C for a short to ground. If the circuit tests normal, replace the RIM.
  3. Install a 3A fused jumper wire between the signal circuit terminal C and ground. Verify the scan tool Rear Compartment Lid Ajar parameter is Ajar.
    4. ⇒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 RIM.
  4. If all circuits test normal, test or replace the rear compartment lid latch.

Component Testing
  1. Ignition OFF, disconnect the harness connector at the rear compartment lid latch.
  2. Test for infinite resistance between the signal terminal C and the ground terminal B with the switch in the open position.
    3. ⇒If not the specified value, replace the rear compartment lid latch.
  3. Test for less than 2 ohms between the signal terminal C and the ground terminal B with the switch in the closed position.
    4. ⇒If greater than the specified range, replace the rear compartment lid latch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Rear Compartment Lid Latch Replacement
    •  Control Module References for RIM replacement, setup, and programming