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Bus (+) Open, Bus (-) Open, Bus Bias Level Too High Or Bus Bias Level Too Low

NOTE: After making any repairs, perform BODY VERIFICATION TEST  under VERIFICATION TESTS.
NOTE: Most common cause for this trouble code to set is ignition switch being off while performing bus test.
  1. If ignition was off during bus test, turn ignition on. Perform verification test to see if fault returns. See BODY VERIFICATION TEST  under VERIFICATION TESTS. If ignition was on during bus test, go to next step.
  2. Turn ignition on, engine off. Disconnect scan tool from Data Link Connector (DLC). Measure voltage between ground and terminal No. 3 (Violet/Brown wire) at DLC. If voltage is not 2.3-2.6 volts, go to step  4 . If voltage is 2.3-2.6 volts, go to next step.
  3. Measure voltage between ground and terminal No. 11 (White/Black wire) at DLC. If voltage is not 2.3-2.6 volts, go to next step. If voltage is 2.3-2.6 volts, replace scan tool cable or scan tool.
  4. Connect scan tool to DLC. Turn ignition off. Disconnect Body Control Module (BCM) connectors. BCM is located with junction block under driver's side instrument panel. See Figure . Measure resistance between BCM terminals No. 3 and 34. See Figure . If resistance is not 100-140 ohms, replace BCM. If resistance is 100-140 ohms, go to next step.
  5. Connect one end of a jumper wire to ground. Using other end of jumper wire, backprobe terminal No. 3 (Violet/Brown wire) at BCM connector "A". See Figure . Turn ignition on. Using scan tool, select BODY, BODY COMPUTER, then SYSTEM TEST. Perform CCD BUS test. If scan tool does not display BUS SHORT TO GROUND, repair open in Violet/Brown wire. If scan tool displays BUS SHORT TO GROUND, go to next step.
  6. Disconnect jumper wire from terminal No. 3 and reconnect jumper wire to terminal No. 34 (White/Black wire) at BCM connector "A". See Figure . Perform CCD BUS test. If scan tool does not display BUS SHORT TO GROUND, repair open in White/Black wire. If scan tool displays BUS SHORT TO GROUND, go to next step.
  7. Turn ignition off. Disconnect Powertrain Control Module (PCM) connectors. PCM is located in engine compartment between left inner fender and power distribution center. Measure resistance between PCM terminals No. 59 and 60. See Figure . If resistance is not 100-140 ohms, replace PCM. If resistance is 100-140 ohms, go to next step.
  8. Connect one end of a jumper wire to ground. Using other end of jumper wire, backprobe terminal No. 59 (Violet/Brown wire) at PCM connector C2. Turn ignition on. Using scan tool, select BODY, BODY COMPUTER, then SYSTEM TEST. Perform CCD BUS test. If scan tool does not display BUS SHORT TO GROUND, repair open in Violet/Brown wire. If scan tool displays BUS SHORT TO GROUND, go to next step.
  9. Disconnect jumper wire from terminal No. 59 and reconnect jumper wire to terminal No. 60 (White/Black wire) PCM connector C2. Perform CCD BUS test. If scan tool does not display BUS SHORT TO GROUND, repair open in White/Black wire. If scan tool displays BUS SHORT TO GROUND, go to next step.
  10. Turn ignition off. Disconnect jumper wire. Measure resistance between ground and terminal No. 3 (Violet/Brown wire) at BCM "A"connector. If resistance is less than 50 ohms, repair short to ground in Violet/Brown wire. If resistance is 50 ohms or more, go to next step.
  11. Measure resistance between ground and terminal No. 34 (White/Black wire) at BCM connector "A". If resistance is less than 50 ohms, repair short to ground in White/Black wire. If resistance is 50 ohms or more, replace BCM.
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