Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

The liftgate module uses the liftgate open switch to determine when the liftgate is in its fully extended and open position. The liftgate module supplies battery voltage to the switch via the liftgate open switch signal circuit. When the liftgate is fully open, the switch is closed. This provides a return path for voltage to the liftgate module via the liftgate open switch ground circuit.

A liftgate open or close function is attempted.

A short to ground on the liftgate open switch signal circuit or a full open switch remaining closed at all times will cause DTC B153B to set.

Liftgate operation is suspended for the ignition cycle.

Schematic Reference

Body Rear End Schematics

Connector End View Reference

Body Rear End Connector End Views

Electrical Information Reference

Scan Tool Reference

1. Attempt to open the liftgate. The liftgate should smoothly open.
2. Attempt to close the liftgate. The liftgate should smoothly close.

1. Ignition OFF, disconnect the harness connector at the liftgate motor assembly.
2. Ignition ON. With a DMM, test for 5 volts between the liftgate open switch signal circuit and ground.

⇒	If not equal to 5 volts, inspect the signal circuit for an open or short to ground. If the circuit/connections test normal, replace the liftgate module.

3. Verify 5 volts are present when connected between the liftgate open switch signal circuit and the liftgate full open switch ground circuit.

⇒	If not equal to 5 volts, repair the open in the ground circuit. If the circuit/connections test normal, replace the liftgate module.

4. Test or replace the liftgate open switch.

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.