DTC 02

DTC2 Power Output Circuit To Courtesy Lights Shorted To B+ Or Ground:

DTC2 Power Output Circuit To Courtesy Lights Shorted To B+ Or Ground (Part 1 Of 2):

DTC2 Power Output Circuit To Courtesy Lights Shorted To B+ Or Ground (Part 2 Of 2):

CIRCUIT DESCRIPTION
The Body Control Module (BCM) controls the inadvertent load (battery rundown) protection feature. The BCM de-energizes circuits 1393 and 328 10 minutes (+/-one minute) after the ignition switch has been turned from the ACC or RUN position to the LOCK or OFF position.

The BCM restores power to circuits 1393 and 328 when:
^ Turning the ignition switch from the LOCK or OFF position to the ACC or RUN position.
^ Removing the key from the ignition lock cylinder.
^ Opening any vehicle door.
^ Turning the I/P dimmer switch to the DOME position.
^ Turning on any interior courtesy light connected to circuit 1393 or 328.
^ The BCM receives a message to unlock the doors from the Remote Control Door Lock Receiver (BCM type 3 or 4 only).
^ Unlocking a door using key (BCM type 4 only).

The inadvertent load (battery rundown) protection feature is mileage-sensitive. Vehicles with less than 15 total driven miles have a 3 minute (+/- 18 seconds) time-out instead of 10 minutes.

CONDITIONS FOR SETTING THE DTC
The BCM detects a short to B+ or ground in circuit 1393 or 328.

ACTION TAKEN WHEN THE DTC SETS
^ The BCM sets Diagnostic Trouble Code (DTC) 2.
^ The inadvertent load (battery rundown) protection feature is disabled when circuit 1393 or 328 is shorted to B+.
^ Interior courtesy lights do not turn on when circuit 1393 or 328 is shorted to ground.

CONDITIONS FOR CLEARING THE DTC
^ A short to B+ or ground in circuit 1393 or 328 is no longer present.
^ After repairs are completed, DTC is cleared by performing the Clearing Diagnostic Trouble Codes (DTCs) procedure.

DIAGNOSTIC AIDS
^ Check for a short to B+ in circuit 1393 or 328.
^ Check for a short to ground in circuit 1393 or 328.
^ Try performing the tests shown while moving wiring and connectors. This can often cause the malfunction to appear.

BCM INPUT/OUTPUT TEST PROCEDURE
1. Turn off the I/P dimmer switch.
2. Turn the ignition switch to the LOCK position.
3. Remove the BCM PRGRM Fuse.
4. Turn the ignition switch to the ACC position.
^ The BCM sounds the chime a number of times equivalent to the BCM type installed on the vehicle.
5. Within one second, turn the ignition switch from the ACC position, to the LOCK position, then back to the ACC position.
^ The BCM sounds any DTCs stored.
6. Turn the I/P dimmer switch to the DOME position.
7. Turn on the interior lamps override switch (enabling the interior lights).

The BCM entered the Input/Output test. The BCM Input/Output consists of:
^ Test 1: De-energizes circuits 1393 and 328 (protected courtesy light output).
^ Test 2: Energizes circuits 1393 and 328.
^ Test 3: Grounds circuit 690 (courtesy lights control).
^ Test 4: Energizes the theft deterrent relay for one second by grounding circuit 301, turning on the exterior lights (BCM type 4 only).
^ Test 5: Energizes the horn relay for 25 ms by grounding circuit 28, sounding the horn (BCM type 4 only).
^ Test 6: Turns on the security indicator lamp by grounding circuit 749 (BCM type 4 only).
^ Test 7: Turns off the security indicator lamp by opening circuit 749 (BCM type 4 only).

The BCM runs the Input/Output test in numerical order.

To move to the next test, cycle the I/P dimmer switch from DOME, to off, back to DOME. The BCM sounds the chime a number equivalent to the Input/Output test number above. The Input/Output test sequence repeats until the ignition switch is turned to the LOCK position.

TEST DESCRIPTION
Numbers below refer to the step numbers on the diagnostic table.
1. Always perform the BCM diagnostic system check before attempting to diagnose this DTC.
2. Performs the BCM Input/Output test. This test energizes and de-energizes circuits 1393 and 328. During this test, the technician can monitor the courtesy lights. If the courtesy lights turn off during this test, circuits 1393 and 328 are in good condition and no short to B+ or ground is present.
3. Checks for a short to B+ in circuit 1393 or 328.
4. Checks for a short to ground in circuit 1393 or 328.