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Bus Short To 5 Volts

NOTE: For connector terminal identification and wiring diagrams, see BODY CONTROL COMPUTER - INTRODUCTION article. Perform VERIFICATION TEST VER-1A  after each repair.
CAUTION: Always turn ignition off prior to disconnecting any module connector.
  1. Turn ignition off. Disconnect Transmission Control Module (TCM), if equipped. TCM is located on right fenderwell, next to washer reservoir. Turn ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS, replace TCM. If scan tool displays BUS SHORT TO 5 VOLTS, go to next step.
  2. Turn ignition off and disconnect Powertrain Control Module (PCM). PCM is located next power distribution center on left inner fenderwell. Turn ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS, go to step  20 . If scan tool displays BUS SHORT TO 5 VOLTS, go to next step.
  3. Turn ignition off and disconnect CCD radio 2-pin connector. Turn ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS, replace radio. If scan tool displays BUS SHORT TO 5 VOLTS, go to next step.
  4. Turn ignition off. Disconnect compass/mini-trip module. Turn ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS, replace compass/mini-trip module. If scan tool displays BUS SHORT TO 5 VOLTS, go to next step.
  5. Turn ignition off. Disconnect anti-lock brake controller module. Turn ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS, replace anti-lock brake controller module. If scan tool displays BUS SHORT 5 VOLTS, go to next step.
  6. Turn ignition off. Disconnect instrument cluster. Turn ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS, replace instrument cluster. If scan tool displays BUS SHORT TO 5 VOLTS, go to next step.
  7. Turn ignition off. Disconnect HVAC module. Turn ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS, replace HVAC module. If scan tool displays BUS SHORT TO 5 VOLTS, go to next step.
  8. Turn ignition off. Disconnect Body Control Module (BCM) connectors. BCM is located on back of junction block under left side of instrument panel. Turn ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS, go to step  12 . If scan tool displays BUS SHORT TO 5 VOLTS, go to next step.
  9. Turn ignition off and wait 5 minutes. Disconnect Air Bag Control Module (ACM) 13-pin connector. ACM is located under center of instrument panel. Turn ignition on. If scan tool does not display BUS SHORT TO 5 VOLTS, replace ACM. If scan tool displays BUS SHORT TO 5 VOLTS, go to next step.
  10. Using external voltmeter, measure voltage between ground and BCM Connector "A" terminal No. 3 (Violet/Brown wire). If voltage is more than 4 volts, repair Violet/Brown wire for short to voltage. If voltage is 4 volts or less, go to next step.
  11. Measure voltage between ground and terminal No. 34 (White/Black wire). If voltage is more than 4 volts, repair White/Black wire for short to voltage. If voltage is less than 4 volts, replace scan tool cable or scan tool as necessary.
  12. Turn ignition off. Using external ohmmeter, measure resistance between Body Control Module (BCM) Black connector "A" terminal No. 3 (Violet/Brown wire) and Gray connector "B" terminal No. 78 (Light Green/Red wire). If resistance is less than 5 ohms, repair short between Violet/Brown wire and Light Green/Red wire. If resistance is 5 ohms or more, go to next step.
  13. Measure resistance between BCM Black connector "A" terminal No. 34 (White/Black wire) and Gray connector "B" terminal No. 78 (Light Green/Red wire). If resistance is less than 5 ohms, repair short between White/Black wire and Light Green/Red wire. If resistance is 5 ohms or more, go to next step.
  14. Measure resistance between BCM Black connector "A" terminals No. 3 (Violet/Brown wire) and No. 32 (Light Blue wire). If resistance is less than 5 ohms, repair short between Violet/Brown wire and Light Blue wire. If resistance is 5 ohms or more, go to next step.
  15. Measure resistance between BCM Black connector "A" terminals No. 32 (Light Blue wire) and No. 34 (White/Black wire). If resistance is less than 5 ohms, repair short between Light Blue wire and White/Black wire. If resistance is 5 ohms or more, go to next step.
  16. Measure resistance between BCM Black connector "A" terminal No. 3 (Violet/Brown wire) and Gray connector "B" terminal No. 79 (Tan wire). If resistance is less than 5 ohms, repair short between Violet/Brown wire and Tan wire. If resistance is 5 ohms or more, go to next step.
  17. Measure resistance between BCM Black connector "A" terminal No. 34 (White/Black wire) and Gray connector "B" terminal No. 79 (Tan wire). If resistance is less than 5 ohms, repair short between White/Black wire and Tan wire. If resistance is 5 ohms or more, go to next step.
  18. Measure resistance between BCM Black connector "A" terminal No. 3 (Violet/Brown wire) and Gray connector "B" terminal No. 48 (Tan/Red wire). If resistance is less than 5 ohms, repair short between Violet/Brown wire and Tan/Red wire. If resistance is 5 ohms or more, go to next step.
  19. Measure resistance between BCM Black connector "A" terminal No. 34 (White/Black wire) and Gray connector "B" terminal No. 48 (Tan/Red wire). If resistance is less than 5 ohms, repair short between White/Black wire and Tan/Red wire. If resistance is 5 ohms or more, replace BCM.
  20. Turn ignition off. Using external ohmmeter, measure resistance between Powertrain Control Module (PCM) connector terminals No. 59 (Violet/Brown wire) and No. 61 (Violet/White wire). If resistance is less than 5 ohms, repair short between Violet/Brown and Violet/White wire. If resistance is 5 ohms or more, go to next step.
  21. Measure resistance between PCM connector terminals No. 60 (White/Black wire) and No. 61 (Violet/White wire). If resistance is less than 5 ohms, repair short between White/Black wire and Violet/White wire. If resistance is 5 ohms or more, replace PCM.
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