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Home >> Dodge and Ram >> 2008 >> Nitro SLT, RWD >> Repair and Diagnosis >> Engine Performance >> System >> DTCS P2314 To U1418, System Checks, O2 Sensor Check, Checking Pcm Power And Ground Circuits, Engine Cranks But No Start >> U0121-Lost Communication With Anti-Lock Brake Module >> Diagnostic Test
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Diagnostic Test

  1. VERIFY DTC IS ACTIVE 
    NOTE: Ensure the IOD fuse is installed and battery voltage is between 10 and 16 volts before proceeding.

    Turn the ignition on.

    With the scan tool, select View DTCs.

    Is this DTC Active? 

    Yes 

    1. Go To  2.

    No 

    1. Perform the Stored Lost Communication test procedure. Refer to DIAGNOSIS AND TESTING .
  2. CHECK FOR ANY OF THE FOLLOWING ACTIVE DTCS 

    With the scan tool, read all active DTCs from all CAN C Bus modules.

    NOTE: Check for CAN C hardware electrical, VIN Missing/Mismatch, battery or ignition related DTCs.

    Does the scan tool display any active DTCs to the conditions listed above? 

    Yes 

    1. Diagnose and repair the DTC(s). Refer to the DIAGNOSTIC CODE INDEX .

    No 

    1. Go To  3.
  3. VERIFY THAT THE ABS IS ACTIVE ON THE BUS 

    With the scan tool, select ECU View.

    Verify that the ABS is active on the bus.

    Is the ABS active on the bus? 

    Yes 

    1. Go To  4.

    No 

    1. Refer to DIAGNOSIS AND TESTING for No Response related diagnostic procedures.
  4. CHECK FOR ADDITIONAL COMMUNICATION RELATED DTCS 

    With the scan tool, select Network View and select Advanced.

    Is there more than one module with active DTCs "Logged Against" the ABS? 

    Yes 

    1. Replace/update the ABS in accordance with the service information.
    2. Perform BODY VERIFICATION TEST - VER 1 .

    No 

    1. Replace the PCM in accordance with the service information.
    2. Perform BODY VERIFICATION TEST - VER 1 .