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Test NS-6C: Repairing No Response Condition

  1. If ignition is not on when NO RESPONSE message is displayed, turn ignition on to get a response. Test is complete. If ignition is on when NO RESPONSE message is displayed, go to next step.
    NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION . For circuit identification and wiring diagram, see CHEROKEE wiring diagram in WIRING DIAGRAMS article.
  2. Turn ignition off. Disconnect Powertrain Control Module (PCM) connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Disconnect scan tool from Data Link Connector (DLC). Clean and/or repair connector as necessary. Using an ohmmeter, check resistance of SCI receive circuit between DLC connector and PCM. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open SCI receive circuit. Perform TEST VER-1A.
  3. Ensure ignition is off. Ensure PCM connectors are still disconnected. Using ohmmeter, check resistance between ground and PCM connector, SCI receive circuit. If resistance is less than 5 ohms, repair SCI receive circuit for short to ground. Perform TEST VER-1A. If resistance is 5 ohms or more, go to next step.
  4. Ensure ignition is off. Ensure PCM connectors are still disconnected. Using ohmmeter, check resistance of SCI transmit circuit between DLC connector and PCM. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open SCI transmit circuit. Perform TEST VER-1A.
  5. Ensure ignition is off. Ensure PCM connectors are still disconnected. Using ohmmeter, check resistance between ground and PCM connector, SCI transmit circuit. If resistance is less than 5 ohms, repair SCI transmit circuit for short to ground. Perform TEST VER-1A. If resistance is 5 ohms or more, go to next step.
  6. Ensure ignition is off. Connect scan tool to functional DLC on another vehicle. Turn ignition on. Using scan tool, attempt to read DTCs. If scan tool does not display NO RESPONSE, replace initial vehicle's PCM. Perform TEST VER-1A. If scan tool displays NO RESPONSE, go to next step.
  7. Ensure ignition is off. Substitute another scan tool adapter cable. Using scan tool, attempt to read DTCs. If scan tool does not display NO RESPONSE, replace original scan tool adapter cable. If scan tool displays NO RESPONSE, go next step.
  8. At this time, scan tool is assumed to be defective. Replace scan tool. Perform TEST VER-1A.
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