Power Liftgate
DTC B2494 (Power Liftgate)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptor
DTC B2494 02
- Liftgate Handle Switch Circuit Short to Ground
Diagnostic Fault Information
Circuit/System Description
The power liftgate button and exterior liftgate handle switch are parallel circuits and provide a single input to the liftgate module (LGM). The liftgate switches are supplied voltage and share a common low reference circuit from the LGM. When the switch contacts close, the LGM 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 9-18 volts.
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
Important: Before testing can be performed the liftgate must be opened. Refer to Opening the Liftgate Without Electrical Power () for the appropriate procedure.
Whenever the LGM loses power or is disconnected, the ignition must be cycled OFF then ON in order to reactivate the LGM.
Reference Information
Schematic Reference
Liftgate Schematics (Liftgate Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Rear Hatch/Gate Description and Operation ()
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
Ignition ON, observe the scan tool Liftgate Handle Sw. Status parameter while pressing and releasing the liftgate switches. The reading should change between Active and Inactive.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connectors at the liftgate exterior switch and liftgate interior switch.
2. Ignition ON, verify the scan tool Liftgate Handle Sw. Status parameter is Inactive.
• If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the LGM.
3. Ignition OFF, connect the harness connector at the exterior liftgate switch.
4. Ignition ON, observe the scan tool Liftgate Handle Sw. Status parameter while pressing and releasing the exterior liftgate switch, the reading should change between Active and Inactive.
• If the parameter does not change, test or replace the exterior liftgate switch.
5. If all circuits test normal, test or replace the interior liftgate switch.
Component Testing
1. Ignition OFF, disconnect the harness connector at the appropriate liftgate switch.
2. Test for infinite resistance between the signal terminal 1 and the low reference terminal 2 with the switch in the open position.
• If not the specified value, replace the liftgate switch.
3. Test for less than 2.0 ohms between the signal terminal 1 and the low reference terminal 2 with the switch in the closed position.
• If greater than the specified range, replace the liftgate switch.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
Control Module References (Programming and Relearning) for LGM replacement, setup, and programming