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For 1990-2009 cars only

DTC B2494 Manual Liftgate

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 B2494 02: Liftgate Handle Switch Circuit Short to Ground

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Liftgate Open Signal -- Exterior Switch

B396E 02

1

1

--

Object Sensors Signal

B153F 02

B153F 05

B153F 05

B153F 03, B153F 07

Pawl Switch Signal

B153A 08

B153A 08

B153A 08

B153A 08

Ratchet Switch Signal

B153A 08

B153A 08

B153A 08

B153A 08

Sector Switch Signal

B153A 08

B153A 08

B153A 08

B153A 08

Liftgate Latch Cinch Control

B2495 02

B2495 04

B2495 01

--

Liftgate Latch Release Control

B2495 02

B2495 04

B2495 01

--

Liftgate Motor Close Control

B396A 02

B396A 04

B396A 01

--

Liftgate Control Module Ground

--

U0230 00

2

--

1. Liftgate Switch Malfunction

2. Liftgate Malfunction

Circuit/System Description

The exterior liftgate handle switch provides a single input to the liftgate control module. The liftgate switch is supplied voltage and a low reference circuit from the liftgate control module. When the switch contacts close, the liftgate control module detects the voltage drop and commands the liftgate to open or close depending upon the position of the liftgate at the time.

Conditions for Running the DTC

The system voltage is 9.5-16 V.

Conditions for Setting the DTC

The liftgate open/close signal circuit is active for longer than 10 minutes.

Action Taken When the DTC Sets

The liftgate open and close functions from the liftgate switches will be inoperative.

Conditions for Clearing the DTC

    • The DTC will be current for as long as the fault is present.
    • When the fault is no longer present, the DTC will be a history DTC.
    • A history DTC will clear after 50 ignition cycles.

Diagnostic Aids

Note: Before testing can be performed the liftgate must be opened. Refer to Opening the Liftgate Without Electrical Power for the appropriate procedure.

Whenever the liftgate control module loses power or is disconnected, the ignition must be cycled OFF then ON in order to reactivate the liftgate control module.

Reference Information

Schematic Reference

Liftgate Schematics

Connector End View Reference

Component 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

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, observe the scan tool Liftgate Handle Switch Status parameter while pressing and releasing the liftgate switch. The reading should change between Active and Inactive.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connectors at the S58A Rear Compartment Lid Unlatch Switch - Exterior.
  2. Ignition ON, verify the scan tool Liftgate Handle Switch Status parameter is Inactive.
  3. If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the K39 Liftgate Control Module.
  4. Connect a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference terminal 3 and verify the scan tool Liftgate Handle Switch Status parameter is Active.
  5. If not the specified value, test the signal circuit and low reference circuit for an open.
  6. If all circuits test normal, test or replace the S58A Rear Compartment Lid Unlatch Switch - Exterior.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the S58A Rear Compartment Lid Unlatch Switch - Exterior.
  2. Test for infinite resistance between the signal terminal 1 and the low reference terminal 2 with the switch in the open position.
  3. If not the specified value, replace the S58A Rear Compartment Lid Unlatch Switch - Exterior.
  4. Test for less than 2.0 Ω between the signal terminal 1 and the low reference terminal 2 with the switch in the closed position.
  5. If greater than the specified range, replace the S58A Rear Compartment Lid Unlatch Switch - Exterior.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Liftgate Outside Handle Replacement
    •  Control Module References for liftgate control module replacement, setup, and programming

DTC B2494 Power Liftgate

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 B2494 02: Liftgate Handle Switch Circuit Short to Ground

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Liftgate Position Sensor 5 V Reference Voltage

B153E 08

2

2

--

Liftgate Disable Signal

1, 2

1

1

--

Liftgate Open Signal -- Exterior Switch

B396E 02

1

1

--

Liftgate Open Signal -- Shut Face Switch

B396E 02

1

1

--

Object Sensors Signal

B153F 02

B153F 05

B153F 05

B153F 03, B153F 07

Open/Close Switches Signal

B396D 02

1, 2

1, 2

--

Pawl Switch Signal

B153A 08

B153A 08

B153A 08

B153A 08

Position Sensor Signal 1

B153E 08

B153E 08

B153E 08

B153E 08

Position Sensor Signal 2

B153E 08

B153E 08

B153E 08

B153E 08

Ratchet Switch Signal

B153A 08

B153A 08

B153A 08

B153A 08

Sector Switch Signal

B153A 08

B153A 08

B153A 08

B153A 08

Liftgate Latch Cinch Control

B2495 02

B2495 04

B2495 01

--

Liftgate Latch Release Control

B2495 02

B2495 04

B2495 01

--

Liftgate Motor Close Control

B396A 02

B396A 04

B396A 01

--

Liftgate Motor Open Control

B396A 02

B396A 04

B396A 01

--

Liftgate Switches Low Reference

--

B153A 08

1

B153E 08

Position Sensor Low Reference

--

B0153E 08

2

--

Mode/Release Switch Ground

--

1

1

--

Liftgate Control Module Ground

--

U0230 00

2

--

1. Liftgate Switch Malfunction

2. Liftgate Malfunction

Circuit/System Description

The exterior liftgate handle switch provides a single input to the liftgate control module. The liftgate switch is supplied voltage and a low reference circuit from the liftgate control module. When the switch contacts close, the liftgate control module detects the voltage drop and commands the liftgate to open or close depending upon the position of the liftgate at the time.

Conditions for Running the DTC

The system voltage is 9.5-16 V.

Conditions for Setting the DTC

The liftgate open/close signal circuit is active for longer than 10 minutes.

Action Taken When the DTC Sets

The liftgate open and close functions from the liftgate switches will be inoperative.

Conditions for Clearing the DTC

    • The DTC will be current for as long as the fault is present.
    • When the fault is no longer present, the DTC will be a history DTC.
    • A history DTC will clear after 50 ignition cycles.

Diagnostic Aids

Note: Before testing can be performed the liftgate must be opened. Refer to Opening the Liftgate Without Electrical Power for the appropriate procedure.

Whenever the liftgate control module loses power or is disconnected, the ignition must be cycled OFF then ON in order to reactivate the liftgate control module.

Reference Information

Schematic Reference

Liftgate Schematics

Connector End View Reference

Component 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

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, observe the scan tool Liftgate Handle Switch Status parameter while pressing and releasing the liftgate switch. The reading should change between Active and Inactive.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connectors at the S58A Rear Compartment Lid Unlatch Switch - Exterior.
  2. Ignition ON, verify the scan tool Liftgate Handle Switch Status parameter is Inactive.
  3. If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the K39 Liftgate Control Module.
  4. Connect a 3 A fused jumper wire between the signal circuit terminal 1 and the low reference terminal 3 and verify the scan tool Liftgate Handle Switch Status parameter is Active.
  5. If not the specified value, test the signal circuit and low reference circuit for an open.
  6. If all circuits test normal, test or replace the S58A Rear Compartment Lid Unlatch Switch - Exterior.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the S58A Rear Compartment Lid Unlatch Switch - Exterior.
  2. Test for infinite resistance between the signal terminal 1 and the low reference terminal 2 with the switch in the open position.
  3. If not the specified value, replace the S58A Rear Compartment Lid Unlatch Switch - Exterior.
  4. Test for less than 2.0 Ω between the signal terminal 1 and the low reference terminal 2 with the switch in the closed position.
  5. If greater than the specified range, replace the S58A Rear Compartment Lid Unlatch Switch - Exterior.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Liftgate Outside Handle Replacement
    •  Control Module References for liftgate control module replacement, setup, and programming