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For 1990-2009 cars only

DTC B2495 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

dd

DTC B2495 01: Liftgate Latch Motor Circuit Short to Battery

DTC B2495 02: Liftgate Latch Motor Circuit Short to Ground

DTC B2495 04: Liftgate Latch Motor Circuit Open Circuit

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Liftgate Relay Switch B+

2

2

--

--

Liftgate Release Switch Signal

B2494 00

B2494 00

B2494 00

--

Liftgate Relay Low Reference

--

2

B3265 00

--

Liftgate Relay Coil Control

B2495 02

2

B2495 01

--

Liftgate Latch Control

--

2

2

--

Liftgate Latch Ground

--

2

2

--

Liftgate Switch Ground

--

1

1

--

1. Liftgate Release Switch Malfunction

2. Liftgate Release Malfunction

Conditions for Running the DTC

The system voltage is 9.5-16 V.

Conditions for Setting the DTC

B2495 01

The liftgate control module detects a short to voltage in the liftgate latch motor open control circuit or the liftgate latch motor close control circuit.

B2495 02

The liftgate control module detects a short to ground in the liftgate latch motor open control circuit or the liftgate latch motor close control circuit.

B2495 04

The liftgate control module detects an open/high resistance in the liftgate latch motor open control circuit or the liftgate latch motor close control circuit.

Action Taken When the DTC Sets

The liftgate will be inoperative in the power and manual modes.

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, command the liftgate to Open with the scan tool, the liftgate should perform the power Open function.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the M31 Liftgate Latch Assembly.
  2. Test for less than 5 Ω between the control circuit terminal 1 and ground
  3. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the K39 Liftgate Control Module.
  4. Test for less than 5 Ω between the control circuit terminal 3 and ground.
  5. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the K39 Liftgate Control Module.
  6. Connect a test lamp between control circuit terminal 1 and ground.
  7. Ignition ON, command the liftgate to Open by pressing and releasing the liftgate interior switch. The test lamp should illuminate while commanding the Open state.
  8. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K39 Liftgate Control Module.
    If the test lamp is always ON, test the control circuit for a short to voltage, if the circuit tests normal, replace the K39 Liftgate Control Module.
  9. Ignition OFF, connect a test lamp between the control circuit terminal 3 and ground.
  10. Connect a 3 A fused jumper wire between the signal circuit terminal 6 and ground.
  11. Ignition ON, command the liftgate to Close by pressing and releasing the liftgate interior switch. The test lamp should illuminate while commanding the Close state.
  12. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K39 Liftgate Control Module.
    If the test lamp is always ON, test the control circuit for a short to voltage, if the circuit tests normal, replace the K39 Liftgate Control Module.
  13. If all circuits test normal, test or replace the M31 Liftgate Latch Assembly.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the M31 Liftgate Latch Assembly.
  2. Install a 20 A fused jumper wire between the control terminal 1 and 12 V. Momentarily install a jumper wire between the control terminal 3 and ground. The M31 Liftgate Latch Assembly should perform the Cinch or Release function.
  3. If the function does not perform as specified, replace the M31 Liftgate Latch Assembly.
  4. Reverse the jumper wires; the M31 Liftgate Latch Assembly should perform the Release or Cinch function.
  5. If the function does not perform as specified, replace the M31 Liftgate Latch Assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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

DTC B2495 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 B2495 01: Liftgate Latch Motor Circuit Short to Battery

DTC B2495 02: Liftgate Latch Motor Circuit Short to Ground

DTC B2495 04: Liftgate Latch Motor Circuit Open Circuit

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 latch motor is a bi-directional motor and cinch or unlatch operation is the result of the direction of the motor rotation. The liftgate control module controls the latch motor through the control circuits by supplying power and ground in the appropriate polarity. The motor control circuits are monitored by the liftgate control module prior to activation for a high or low condition and during motor operation for an insufficient current flow condition.

Conditions for Running the DTC

The system voltage is 9.5-16 V.

Conditions for Setting the DTC

B2495 01

The liftgate control module detects a short to voltage in the liftgate latch motor open control circuit or the liftgate latch motor close control circuit.

B2495 02

The liftgate control module detects a short to ground in the liftgate latch motor open control circuit or the liftgate latch motor close control circuit.

B2495 04

The liftgate control module detects an open/high resistance in the liftgate latch motor open control circuit or the liftgate latch motor close control circuit.

Action Taken When the DTC Sets

The liftgate will be inoperative in the power and manual modes.

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, command the liftgate to Open with the scan tool, the liftgate should perform the power Open function.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the M31 Liftgate Latch Assembly.
  2. Test for less than 5 Ω between the control circuit terminal 1 and ground
  3. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the K39 Liftgate Control Module.
  4. Test for less than 5 Ω between the control circuit terminal 3 and ground.
  5. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If circuits test normal, replace the K39 Liftgate Control Module.
  6. Connect a test lamp between control circuit terminal 1 and ground.
  7. Ignition ON, command the liftgate to Open by pressing and releasing the liftgate interior switch. The test lamp should illuminate while commanding the Open state.
  8. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K39 Liftgate Control Module.
    If the test lamp is always ON, test the control circuit for a short to voltage, if the circuit tests normal, replace the K39 Liftgate Control Module.
  9. Ignition OFF, connect a test lamp between the control circuit terminal 3 and ground.
  10. Connect a 3 A fused jumper wire between the signal circuit terminal 6 and ground.
  11. Ignition ON, command the liftgate to Close by pressing and releasing the liftgate interior switch. The test lamp should illuminate while commanding the Close state.
  12. If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K39 Liftgate Control Module.
    If the test lamp is always ON, test the control circuit for a short to voltage, if the circuit tests normal, replace the K39 Liftgate Control Module.
  13. If all circuits test normal, test or replace the M31 Liftgate Latch Assembly.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the M31 Liftgate Latch Assembly.
  2. Install a 20 A fused jumper wire between the control terminal 1 and 12 V. Momentarily install a jumper wire between the control terminal 3 and ground. The M31 Liftgate Latch Assembly should perform the Cinch or Release function.
  3. If the function does not perform as specified, replace the M31 Liftgate Latch Assembly.
  4. Reverse the jumper wires; the M31 Liftgate Latch Assembly should perform the Release or Cinch function.
  5. If the function does not perform as specified, replace the M31 Liftgate Latch Assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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