B1480

DTC B1480

CIRCUIT DESCRIPTION
The battery rundown protection function allows the body control module (BCM) to disable the interior lamps 20 minutes after the ignition switch is turned OFF. The BCM monitors the output of the inadvertent power relay and the inadvertent power relay control circuit.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC B1480 Battery Rundown Protection Circuit

CONDITIONS FOR RUNNING THE DTC
The system voltage must be between 9-16 volts.

CONDITIONS FOR SETTING THE DTC
- When the inadvertent power relay control circuit is shorted to ground
- When there is an open or short to battery voltage on the inadvertent power relay ground circuit
- An open CTSY fuse or open in the battery supply circuit to the inadvertent power relay
- The above conditions must be met for 0.5 second.

ACTION TAKEN WHEN THE DTC SETS
The following lamps will be disabled:
- The courtesy lamps
- The instrument panel (I/P) compartment lamp
- The reading lamps
- The vanity mirror lamps, if equipped

CONDITIONS FOR CLEARING THE MIL/DTC
- The conditions for setting the DTC are no longer present.
- A history DTC will clear after 40 malfunction-free ignition cycles.
- The powertrain control module (PCM) receives the clear code command from the scan tool.

DIAGNOSTIC AIDS
Check for an open in the battery feed circuit to the inadvertent power relay or an open CTSY LP fuse.

TEST DESCRIPTION

Steps 1 - 13:

The numbers below refer to the step numbers on the diagnostic table.
2. Listen for an audible click when the inadvertent power 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 inadvertent power relay. The CTSY fuse supplies power to the coil side of the inadvertent power relay.
4. This step verifies that the BCM is providing ground to the inadvertent power relay.
5. This step tests if a ground is constantly applied to the inadvertent power relay.
6. Since this is a general circuit malfunction code, it is necessary to test for both a short to voltage as well as an open on this circuit.