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Engine Cranks But Does Not Start

NOTE: Diagnostic tests are written specifically for Chrysler's Diagnostic Readout Box (DRBIII(R)) scan tool. A generic scan tool may not be capable of performing all necessary test functions.
NOTE: For component locations and connector identification, see COMPONENT LOCATIONS and CONNECTOR IDENTIFICATION in appropriate SELF-DIAGNOSTICS article. After each repair procedure has been completed, reconnect all components.
NOTE: For circuit identification and wiring diagram, see WIRING DIAGRAMS  . After each repair procedure has been completed, reconnect all components. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS in appropriate SELF-DIAGNOSTICS article to ensure system is functioning properly.
  1. The following list of items must be checked before continuing with any no-start tests.
    • Check for 12 volts at PCM Fused Ignition Switch Output (Start) Circuit in PCM C1 harness connector during cranking.
    • The battery must be fully charged and in good condition. A low charged battery may produce invalid test results. If the battery is low, charge the battery and then attempt to start the vehicle by cranking the engine for 15 seconds, 3 consecutive times. This will allow any DTCs to set that may have been erased due to a dead battery. Try to communicate with PCM if not able to communicate check fuses.
    • Ensure the Power and Ground circuits to the PCM are okay. See COMPUTERIZED ENGINE CONTROLS in appropriate SYSTEM & COMPONENT TESTING article.
    • Make sure the PCM communicates with the DRBIII(R) and that there are no DTCs stored in the PCM memory. See SELF-DIAGNOSTIC SYSTEM in appropriate SELF-DIAGNOSTICS article.
    • If the PCM reports a No Response condition, diagnose communication failure. See COMMUNICATIONS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
    • Ensure PCI bus is functional. Using scan tool, attempt to communicate with instrument cluster and Sentry Key Immobilizer Module (SKIM). If scan tool does not communicate with instrument cluster or SKIM, diagnose communication failure. See COMMUNICATIONS in appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
    • Using scan tool, select CLEAR PCM (BATT DISCONNECT). Crank engine over several times. Using scan tool, check for DTCs. If any DTCs are present, perform appropriate diagnostic test before continuing. See appropriate SELF-DIAGNOSTICS article.

    Were any problems found? If yes, repair as necessary. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS in appropriate SELF-DIAGNOSTICS article. If no, go to next step.

  2. Check for any open fuses in the Power Distribution Center (PDC) and Junction Block that may be related to the no-start condition. PDC is located in engine compartment. Junction Block is located on left end of instrument panel. Are any of the fuses open? If yes, replace the open fuse and check the related circuit(s) for a short to ground. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS in appropriate SELF-DIAGNOSTICS article. If no, go to next step.
  3. Turn the ignition on. With the DRBIII(R), under DTCs and Related Functions, read the Secondary Indicators while cranking the engine. Are there any Secondary Indicators present while cranking the engine? If yes, perform appropriate symptom test related to the Secondary Indicator that was reported by the DRBIII(R). See TROUBLE SHOOTING - NO CODES article. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS in appropriate SELF-DIAGNOSTICS article. If no, go to next step.
  4. Start the engine. With the DRBIII(R) in Miscellaneous, check the Set Sync Signal. Is the Set Sync Signal within specifications? If yes, go to next step. If no, use the DRBIII(R) and synchronize the Camshaft and Crankshaft Position Sensors. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS in appropriate SELF-DIAGNOSTICS article.
  5. With the DRBIII(R) in Sensors, check the Current CKP Count while cranking the engine. Does the CKP Counter change while cranking the engine? If yes, go to next step. If no, perform appropriate diagnostics. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS article.
  6. With the DRBIII(R) in Sensors, check the Current CMP Count while cranking the engine. Does the Current CMP Count change while cranking the engine? If yes, go to next step. If no, perform appropriate diagnostics. See DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS article.
  7. Check the following additional items as possible causes for no-start condition:
    • Fuel must be free of contamination.
    • Engine exhaust system must be free of restrictions or leaks.
    • Engine compression must be within specification.
    • Engine valve timing must be within specification.
    • Fuel injectors must be free of restrictions. Ensure connectors are installed on injectors.

    Are there any mechanical problems? If yes, repair as necessary. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS in appropriate SELF-DIAGNOSTICS article. If no, go to next step.

  8. Turn the ignition off. Remove the ASD relay from the PDC. Disconnect the PCM harness connectors. Verify the ASD Relay is getting Fused B+ voltage before continuing. Measure the resistance of the ASD Relay Output circuit from terminal No. 87 at the ASD Relay connector in the PDC to the PCM C3 harness connector, Ignition Coil (2.4L), Coil On Plugs (3.7L and 4.7L), Ignition Coil Rail (4.0L) and the Fuel Injectors. See WIRING DIAGRAMS  . Is the resistance below 5.0 ohms? If yes, go to next step. If no, repair the open ASD Relay Output circuit. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS in appropriate SELF-DIAGNOSTICS article.
  9. Verify that the Fuel tank is not empty before continuing. Check fuel delivery. See FUEL SYSTEMS in SYSTEM & COMPONENT TESTING article. Was the No-Start condition solved after following the above diagnostic test? If yes, test is complete. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS in appropriate SELF-DIAGNOSTICS article. If no, check for contamination/water in the fuel. Ensure the fuel being used in vehicle meets manufacturer's fuel requirement of a high quality unleaded gasoline having an octane rating of 87. Perform POWERTRAIN VERIFICATION TEST VER-5 under VERIFICATION TESTS in appropriate SELF-DIAGNOSTICS article.
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