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Retained Accessory Power (Rap) Diagnostic System Check

  1. Ensure battery condition, cold cranking amperage and reserve capacity meet specifications. Replace as necessary. Install scan tool to Data Link Connector (DLC). If scan tool powers up, go to next step. If scan tool does not power up, go to SCAN TOOL DOES NOT POWER UP  .
  2. Turn ignition on, engine off. Try to establish scan tool communication with BCM. If communication with BCM is established, go to next step. If communication with BCM is not established, go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE  .
  3. Select display DTC function for BCM. Record all displayed DTCs and status of displayed DTCs. If DTCs are displayed, go to next step. If no DTCs are displayed, attempt to diagnose system by symptom. Go to SYMPTOM TESTS  .
  4. If scan tool displays any DTCs that begin with "U", go to SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE  . If scan tool does not display any DTCs that begin with "U", go to next step.
  5. If scan tool displays DTC B1000, B1013 or B1015, go to BODY CONTROL MODULE (BCM) DTC DEFINITIONS  . If scan tool does not display DTC B1000, B1013 or B1015, go to next step.
  6. If scan tool displays DTC B1334, B1339, B1354 or B1422, go to BODY CONTROL MODULE (BCM) DTC DEFINITIONS  . If scan tool does not display DTC B1334, B1339, B1354 or B1422, go to next step.
  7. If scan tool displays DTC B1477 or B1478, go to BODY CONTROL MODULE (BCM) DTC DEFINITIONS  and perform appropriate test. If scan tool does not display DTC B1477 or B1478, go to SYMPTOM TESTS  .
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