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B3820



DTC B3820

CIRCUIT DESCRIPTION
The body control module (BCM) grounds the control side of the left rear power window down relay upon receiving a class 2 message from the driver door module (DDM).

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC B3820 Left Rear Window Down Control Circuit

CONDITIONS FOR RUNNING THE DTC
- Battery voltage is between 9-16 volts.
- The BCM has received a class 2 message from the DDM and has grounded the left rear power window down relay control circuit.

CONDITIONS FOR SETTING THE DTC
- When the BCM has grounded the left rear power window down relay control circuit and the control circuit is shorted to battery positive voltage.
- The above condition is met for 250 milliseconds.

ACTION TAKEN WHEN THE DTC SETS
The left rear power window will be inoperative from both the driver and left rear power window switches.

CONDITIONS FOR CLEARING THE DTC
When the fault is no longer present, the BCM changes the current DTC to a history DTC. The BCM will clear the history DTC after 50 fault free ignition cycles.

TEST DESCRIPTION

Step 1 - Step 13:




The numbers below refer to the step numbers on the diagnostic table.
2. Listen for an audible click when the left rear power window relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
3. This step tests for voltage at the coil side of the left rear power window down relay.
4. This step verifies that the BCM is providing ground to the left rear power window down relay.
5. This step tests if ground is constantly being applied to the left rear power window down relay.