Input/Output Diagnostics

1. After all DTCs have been displayed, BCM provides individual input and output diagnostic checks for various functions. BCM will flash seat belt indicator and sound a chime when operating the following inputs:
   • All reading courtesy light switches.
   • Power door lock switches.
   • Left front, right front and liftgate door lock cylinders.
   • Left front, right front and liftgate door ajar switches.
   • Sliding door jamb switch.
   • Driver's seat belt switch.
   • Headlights OFF switch.
   • Glove box light switch.
   • Keyless entry requests for door lock/unlock or alarm (BCM-4).
   • Shock sensor.
   • Sunshade illuminated mirrors.
   • Turn signal switch.

   If the proper feedback is not received, then there is an open or short in that circuit or a faulty component.

2. To test BCM outputs, ensure BCM is in diagnostics mode. Turn instrument panel dimmer switch to DOME position. BCM will then perform the following tests:

• Test No. 1 - De-energizes circuits No. 1393 (Dark Blue wire) and No. 328 (Purple wire) to turn off interior courtesy lights.
• Test No. 2 - Energizes circuits No. 1393 (Dark Blue wire) and No. 328 (Purple wire) to turn on interior courtesy lights.
• Test No. 3 - Grounds circuit No. 690 (Gray/Black wire) to turn on interior courtesy lights.
• Test No. 4 (BCM-4) - Grounds circuit No. 301 (Brown/White wire) to energize theft deterrent relay for one second and turn on exterior lights.
• Test No. 5 (BCM-4) - Grounds circuit No. 28 (Black wire) to energize horn relay for 25 milliseconds and sound horn.
• Test No. 6 (BCM-4) - Grounds circuit No. 749 (Yellow wire) to turn on security indicator light.
• Test No. 7 (BCM-4) - Opens circuit No. 749 (Yellow wire) to turn off security indicator light.

BCM will perform output tests in numerical order. To move to next test, cycle instrument panel dimmer switch from DOME position to off, then back to DOME position. BCM will sound a chime to indicate which test is being performed.