B2482

DTC B2482 Backup Lamp Relay Circuit:

DTC B2482 Backup Lamp Relay Circuit (Part 1 Of 2):

DTC B2482 Backup Lamp Relay Circuit (Part 2 Of 2):

CIRCUIT DESCRIPTION
The backup lamp circuit is part of a standard backup lamp system except for the addition of a relay and the Body Control Module (BCM) providing a control circuit. The BCM can ground CKT 38 in order to energize the relay and turn ON the backup lamps, allowing the backup lamps to be used for UTD and approach lighting functions. The BCM monitors the voltage level on the backup lamp control circuit. When the BCM commands the relay ON, the voltage level on the control circuit should be low. When the relay is OFF, the voltage level should be high. If the BCM detects a voltage level other than expected, a malfunction is present and a DTC will set.

CONDITIONS FOR SETTING THE DTC
^ The BCM detects a low voltage level (an open or a short to ground) in CKT 38.
^ The BCM can only test for this condition when the BCM is not attempting to energize the backup lamp relay.
^ The condition must be present for 2 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ Stores a DTC B2482 in the BCM memory.
^ No driver warning message will be displayed for this DTC.

CONDITIONS FOR CLEARING THE DTC
^ This DTC requires an ignition cycle in order to change from current to history.
^ The BCM requests an active backup lamp relay.
^ The BCM no longer detects a high voltage level in CKT 38 only when the BCM is not attempting to energize the backup lamp relay.
^ A history DTC will clear after 50 consecutive ignition cycles if the condition for the malfunction is no longer present.
^ Use the PC clearing DTCs feature.
^ Use a scan tool.

DIAGNOSTIC AIDS
^ The following conditions may cause an intermittent malfunction:
- There is an intermittent open or short to ground in CKT 38.
- There are poor connections at the BCM, the underhood electrical center, or the backup lamp relay terminals.
- There is an internal backup lamp relay open or short.
^ If CKT 38 is shorted to ground, the backup lamp will remain ON at all times. If CKT 38 is open, the backup lamp will remain OFF at all times.
^ If the DTC is a history DTC, the problem may be intermittent. Perform the tests shown while moving related wiring and connectors. This can often cause the malfunction to occur. Refer to Intermittents and Poor Connections. Intermittents and Poor Connections

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
2. This test determines if there is an open in the underhood electrical center or fuse.
3. This test determines if there is a short to ground in the backup lamp circuit.
4. This test checks the resistance of the backup lamp relay coil.
5. This test checks for an internal backup lamp relay short.
6. This test checks for an internal backup lamp relay short.
7. This test checks if the BCM can properly control the backup lamp relay by commanding the BCM to ground CKT 38.
8. This test determines if there is an open in CKT 38.
11. This test determines if the BCM is causing the short to ground.