GM Service Manual Online
For 1990-2009 cars only

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.

DTC Descriptor

DTC B2730: Interior Trunk/Hatch/Liftglass Release Sw Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Liftgate Control Module B+

2

2

--

--

Liftgate Position Sensor 5V Reference Voltage

2

2

2

--

Full Open Signal

B153B 02

2

2

--

Liftgate Disable Signal

1, 2

1

1

--

Liftgate Open Signal

B2730

1

1

--

Object Sensors Signal

B153F 03

2

B153F 07

--

Open/Close Switches Signal

B2494 02

1, 2

1, 2

--

Pawl Switch Signal

B153A 00

B153A 00

B153A 00

--

Position Sensor Signal 1

B153E 02

B153E 05

B153E 05

--

Position Sensor Signal 2

B153E 02

B153E 05

B153E 05

--

Ratchet Switch Signal

B153A 00

B153A 00

B153A 00

--

Sector Switch Signal

B153A 00

B153A 00

B153A 00

--

Disengage Clutch Control

B396B 02

B396B 04

B396B 01

--

Engage Clutch Control

B396B 02

B396B 04

B396B 01

--

Liftgate Latch Cinch Control

B2495 02

B2495 05

B2495 01

--

Liftgate Latch Release Control

B2495 02

B2495 05

B2495 01

--

Liftgate Motor Close Control

B396A 02

B396A 04

B396A 01

--

Liftgate Motor Open Control

B396A 02

B396A 04

B396A 01

--

Full Open Low Reference

--

2

2

--

Liftgate Switches Low Reference

--

1

1

--

Position Sensor Low Reference

--

2

2

--

I/P Switch Ground

--

1

1

--

Liftgate Control Module Ground

--

2

2

--

1. Liftgate Switch Malfunction

2. Liftgate Malfunction

Circuit/System Description

Pressing the I/P switch assembly closes a contact providing a ground for the Liftgate Open circuit. The power liftgate module (PLGM) will detect the voltage drop and command the liftgate to open or close depending upon the position of the liftgate.

Conditions for Running the DTC

Battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

This DTC will set when the LGM detects a fault in the Liftgate Open circuit.

Action Taken When the DTC Sets

    • The BCM stores the DTC to memory.
    • The lift switch will be inoperative.

Conditions for Clearing the DTC

    • This DTC will change from current to history when the fault is no longer present.
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • The technician issues a scan tool CLEAR DTCs command.

Reference Information

Schematic Reference

Release Systems Schematics

Connector End View Reference

Vehicle Access Connector End Views

Description and Operation

Rear Hatch/Gate Description and Operation

Electrical Information Reference

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

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions

Circuit/System Verification

Ignition ON, observe the Int Trunk/Liftglass Sw parameter while pressing the I/P Switch Assembly. The reading should change between Active and Inactive.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the I/P Switch.
  2. Ignition ON, verify the scan tool Int Trunk/Liftglass Sw is Inactive.
  3. If not the specified value, test the signal circuit terminal 7 for a short to ground. If the circuit tests normal, replace the PLGM.
  4. Install a 3A fused jumper wire between the signal circuit terminal 7 and ground. Verify the scan tool Int Trunk/Liftglass Sw is Active.
  5. 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 PLGM.
  6. If all circuits test normal, test or replace the I/P Switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup, and programming