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Test 4A - No Response From Body Control Module

  1. If ignition was off during BUS test, turn ignition on. If ignition was on during BUS test, turn ignition on, engine off. Disconnect scan tool. Using external voltmeter, measure voltage between ground and DLC terminal No. 3 (Violet/Brown wire). If voltage is not 1.8-2.6 volts, go to step 3).
  2. If voltage is 1.8-2.6 volts, measure voltage between ground and DLC terminal No. 11 (White/Black wire). If voltage is not 1.8-2.6 volts, go to next step. If voltage is 1.8-2.6 volts, replace scan tool cable or scan tool.
  3. Disconnect Body Control Module (BCM) connectors. BCM is under left corner of instrument panel. Using external ohmmeter, measure resistance between terminals No. 19 and 20 on BCM component connector. If resistance is not 100-140 ohms, replace BCM. If resistance is 100-140 ohms, go to next step.
  4. Connect jumper wire between ground and terminal No. 19 (Violet/Brown wire) on BCM Black connector. 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 Violet/Brown wire. If scan tool displays BUS SHORT TO GROUND, go to next step.
  5. Move jumper wire to BCM Black connector, terminal No. 20 (White/Black wire). Perform CCD BUS test. If scan tool does not display BUS SHORT TO GROUND, repair open White/Black wire. If scan tool displays BUS SHORT TO GROUND, go to next step.
  6. Using external voltmeter, measure voltage between ground and BCM White connector, terminal No. 8 (Violet wire). If voltage is 10 volts or less, repair open Violet wire. If voltage is more than 10 volts, go to next step.
  7. Measure voltage between ground and BCM White connector, terminal No. 15 (Brown/Pink wire). If voltage is 10 volts or less, repair open Brown/Pink wire. If voltage is more than 10 volts, go to next step.
  8. Using external ohmmeter, measure resistance between ground and BCM White connector, terminal No. 24 (Black wire). If resistance is 5 ohms or greater, repair open Black wire. If resistance is less than 5 ohms, replace BCM.
NOTE: For connector terminal identification, refer to CONNECTOR IDENTIFICATION  . For wiring diagrams, refer to WIRING DIAGRAMS  . After each repair, perform TEST VER-1A  .
CAUTION: Always turn ignition off prior to disconnecting any module connector.
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