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Bus Short To Battery

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 BATTERY, replace TCM. If scan tool displays BUS SHORT TO BATTERY, go to next step.
  2. Turn ignition off and disconnect Powertrain Control Module (PCM). PCM is located next power distribution center. Turn ignition on. If scan tool does not display BUS SHORT TO BATTERY, go to step  15 . If scan tool displays BUS SHORT TO BATTERY, 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 BATTERY, replace radio. If scan tool displays BUS SHORT TO BATTERY, 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 BATTERY, go to step  14 . If scan tool displays BUS SHORT TO BATTERY, 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 BATTERY, replace anti-lock brake controller module. If scan tool displays BUS SHORT TO BATTERY, go to next step.
  6. Turn ignition off. Disconnect instrument cluster. Turn ignition on. If scan tool does not display BUS SHORT TO BATTERY, go to step  13 . If scan tool displays BUS SHORT TO BATTERY, go to next step.
  7. Turn ignition off. Disconnect HVAC module. Turn ignition on. If scan tool does not display BUS SHORT TO BATTERY, replace HVAC module. If scan tool displays BUS SHORT TO BATTERY, go to next step.
  8. Turn ignition off. Disconnect Body Control Module (BCM) connectors. BCM is located on back of junction block. Junction block is located under left side of instrument panel. Turn ignition on. If scan tool does not display BUS SHORT TO BATTERY, go to step  12 . If scan tool displays BUS SHORT TO BATTERY, 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 BATTERY, replace ACM. If scan tool displays BUS SHORT TO BATTERY, go to next step.
  10. Turn ignition off. Using external voltmeter, measure voltage between ground and BCM Connector "A", terminal No. 3 (Violet/Brown wire). If voltage is more than 8 volts, repair Violet/Brown wire for short to voltage. If voltage is 8 volts or less, go to next step.
  11. Measure voltage between ground and terminal No. 34 (White/Black wire). If voltage is more than 8 volts, repair White/Black wire for short to voltage. If voltage is less than 8 volts, replace scan tool cable or scan tool as necessary.
  12. Using external ohmmeter, measure resistance between ground and BCM connector "A" terminal No. 10 (Black/Light Green wire). If resistance is 5 ohms or more, repair open Black/Light Green wire. If resistance is less than 5 ohms, replace BCM.
  13. Turn ignition off. Using external ohmmeter, measure resistance between ground and instrument cluster 13-pin connector terminal No. 7 (Black/Light Green wire). If resistance is 5 ohms or more, repair open Black/Light Green wire circuit. If resistance is less than 5 ohms, replace instrument cluster.
  14. Turn ignition off. Using external ohmmeter, measure resistance between ground and compass/mini-trip computer connector terminal No. 3 (Black/Light Green wire). If resistance is 5 ohms or more, repair open Black/Light Green wire circuit. If resistance is less than 5 ohms, replace compass/mini-trip computer.
  15. Turn ignition off. Using external ohmmeter, measure resistance between Powertrain Control Module (PCM) connector terminals No. 44 (Orange wire) and No. 59 (Violet/Brown wire). PCM is located on left inner fenderwell, near battery. If resistance is less than 5 ohms, repair short between Orange wire and Violet/Brown wire. If resistance is 5 ohms or more, go to next step.
  16. Measure resistance between PCM connector terminals No. 44 (Orange wire) and No. 60 (White/Black wire). If resistance is less than 5 ohms, repair short between Orange wire and White/Black wire. If resistance is 5 ohms or more, replace PCM.
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