DTC B2494 (Manual Liftgate)
|
DTC B2494 (Manual Liftgate)
|
DTC B2494 00
Liftgate Handle Switch Circuit
Diagnostic Fault Information
|
Circuit
|
Short to Ground
|
Open/High Resistance
|
Short to Voltage
|
Signal Performance
|
Liftgate Release Switch Signal
|
B2494 00
|
1
|
1
|
-
|
1. Liftgate Release Switch Malfunction
|
Circuit/System Description
|
The BCM supplies a 12V signal to the signal circuit of the exterior liftgate handle switch and when the release switch is activated the signal circuit voltage goes low. The BCM controls the liftgate release actuator via the liftgate latch release relay. When the release switch signal is activated, the BCM enables the liftgate latch release relay by applying battery voltage to the liftgate latch release relay supply circuit and the relay is energized when the BCM grounds the liftgate latch release relay control circuit. When the relay is energized battery voltage is supplied to the liftgate release actuator through the liftgate release actuator control circuit.
Conditions for Running the DTC
|
The system voltage is 9-18 V.
Conditions for Setting the DTC
|
The liftgate release switch signal circuit is active for greater than 30 seconds.
Action Taken When the DTC Sets
|
The BCM will ignore the signal from the exterior liftgate handle switch
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.
|
Before testing can be performed the liftgate must be opened. Refer to
Opening the Liftgate Without Electrical Power
for the appropriate procedure.
If the vehicle has a history of the liftgate opening unexpectedly, inspect the point where the wires enter the exterior liftgate handle switch for corrosion or evidence of water intrusion.
Schematic Reference
Release Systems Schematics
Connector End View Reference
Component Connector End Views
Description and Operation
Liftgate Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References
for scan tool information
Circuit/System Verification
|
1.
|
DTC B2494 should not be set as a history DTC.
|
2.
|
If DTC B2494 is set only as history, replace the tailgate unlatch switch.
|
3.
|
With the doors unlocked, press the tailgate's unlatch switch. The tailgate will release when the switch is pressed and released.
|
1.
|
With the ignition OFF, disconnect the cable connector at S45B unlatch switch.
|
2.
|
Test for less than 10 Ω between the ground circuit terminal 1 and ground.
|
3.
|
If greater than the specified range, test the ground circuit for an open/high resistance.
|
4.
|
Test for greater than 10 Ω between the signal circuit terminal 2 and ground connection 1.
|
5.
|
If less than the specified range, test the signal circuit for a short to ground or open/high resistance.
|
6.
|
If all circuits test normal, test or replace the S45B liftgate unlatch switch.
|
1.
|
Ignition OFF, disconnect the harness connector at the S45B liftgate unlatch switch.
|
2.
|
Test for infinite resistance between the signal terminal 2 and the ground terminal 1 with the switch in the open position.
|
3.
|
If not the specified value, replace the S45B liftgate unlatch switch.
|
4.
|
Test for less than 2.0 Ω between the signal terminal 2 and the ground terminal 1 with the switch in the closed position.
|
5.
|
If greater than the specified range, replace the S45B liftgate unlatch switch.
|
Perform the
Diagnostic Repair Verification
after completing the diagnostic repair.