• 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.

The power liftgate has a feature that detects the motion of a foot under the rear fascia, this allows the operator to open the liftgate when his or her hands are full of packages. As an indicator that the action has been properly preformed, the liftgate hands-free sensor control module will send a serial data message to the liftgate control module to command the liftgate to release and power open and the liftgate control module will send a serial data message to the body control module to command the tail lights to flash 3 times

Battery voltage is between 9–16 V.

• The liftgate control module has received a serial data message that an invalid signal from the upper hands free sensor has been detected by the hands-free liftgate sensor control module.
• The condition must be present for greater than 30 seconds

• The liftgate control module has received a serial data message that an invalid signal from the lower hands free sensor has been detected by the hands-free liftgate sensor control module.
• The condition must be present for greater than 30 seconds.

An internal malfunction has been detected by the liftgate control module

The liftgate control module detects the calibration files in the hands-free liftgate sensor control module does not match the calibration files contained within the liftgate control module.

The hands-free feature will be inoperative

• 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.

The hands-free function will only be allowed if certain operating criteria are met. Any of the following may cause the hands-free system not to function:

• The hands-free function has been disabled by a setting in the Vehicle Personalization menu
• The Keyless Access function has been disabled
• The keyless entry transmitter is not within range
• The kicking motion is incorrectly preformed
• The interior liftgate control switch has not been set to the 3/4 or Max position
• A loose or misaligned hands-free sensor

Liftgate Schematics

Master Electrical Component List

Liftgate Description and Operation

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

Control Module References for scan tool information

Note: Verify the vehicles Passive Entry functions have not been disabled, refer to the vehicle owners manual for more information.

1. Ignition ON.

Note: The keyless entry transmitter must be within 1 meter (3 feet) of the liftgate

2. Verify the tail lights flash 3 times and the power liftgate opens while performing a kicking motion behind and under the rear fascia.
• If the tail lamps flash but the liftgate does not open

  Refer to Power Liftgate Malfunction

• If the tail lamps do not flash

  Refer to Circuit/System Testing.

• If the tail lamps flash and the liftgate does open
3. All OK.

1. Ignition OFF, disconnect the X2 harness connector at the K171 Hands-Free Liftgate Sensor Control Module.
2. Test for less than 1 Ω between the B275A Hands-Free Liftgate Sensor—Upper signal circuit terminal 1 and the signal circuit terminal 2.
• If 1 Ω or greater
• Replace the B275A Hands-Free Liftgate Sensor—Upper
• If less than 1 Ω
3. Ignition OFF, disconnect the X3 harness connector at the K171 Hands-Free Liftgate Sensor Control Module.
4. Test for less than 1 Ω between the B275B Hands-Free Liftgate Sensor-Lower signal circuit terminal 1 and the signal circuit terminal 2.
• If 1 Ω or greater
• Replace the B275B Hands-Free Liftgate Sensor-Lower
• If less than 1 Ω
5. If all circuits test normal, replace the K171 Hands-Free Liftgate Sensor Control Module.

Perform the Diagnostic Repair Verification after completing the repair

• Rear Closure Hands Free Sensor Replacement
• Control Module References for liftgate hands-free sensor control module replacement, programming and setup