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Home >> Fiat >> 2013 >> 500e >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Electric Vehicle Control Unit (EVCU) Module - DTCS B12A4-11 To P1138 - 500E >> Diagnosis And Testing >> P0685-ASD/Main Control Circuit >> Diagnostic Test
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Diagnostic Test

  1. CHECK IF THE DTC IS ACTIVE 
    1. Turn the ignition on.
    2. With the scan tool, read Electric Vehicle Control Unit (EVCU) DTCs.

      Is the status for this DTC Active?

      Yes 

      • Go To  2

      No 

  2. CHECK THE ASD RELAY 
    1. Turn the ignition off. Remove the key from the Ignition Switch, close doors and allow the EVCU to shut down.
      NOTE:

      Allow up to two minutes for the EVCU to shut down. Opening the vehicle door will interrupt the shut down process.

    2. Install a known good substitute relay in place of the ASD relay.
    3. Turn the ignition on.
    4. With the scan tool, erase Electric Vehicle Control Unit EVCU DTCs.
    5. Turn the ignition off. Remove the key from the Ignition Switch, close doors and allow the EVCU to shut down.
    6. Turn the ignition on.
    7. With the scan tool, read EVCU DTCs.

      Does this DTC reset?

      Yes 

      • Go To  3

      No 

      • Replace the ASD relay.
      • Perform the EVCU VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  3. CHECK THE (F342) ASD RELAY CONTROL CIRCUIT FOR A SHORT TO VOLTAGE 
    1. Turn the ignition off. Remove the key from the Ignition Switch, close doors and allow the EVCU to shut down.
    2. Remove the substitute ASD Relay.
    3. Disconnect the EVCU C1 harness connector.
    4. Turn the ignition on.
    5. Measure the voltage of the (F342) ASD Relay Control circuit.

      Is there any voltage present?

      Yes 

      • Repair the (F342) ASD Relay Control circuit for a short to voltage.
      • Perform the EVCU VERIFICATION TEST. Refer to STANDARD PROCEDURE .

      No 

      • Go To  4
  4. ELECTRIC VEHICLE CONTROL UNIT (EVCU) 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the ASD Relay and the Electric Vehicle Control Unit (EVCU).
    2. Look for any chafed, pierced, pinched or partially broken wires.
    3. Look for broken, bent, pushed out or corroded terminals.
    4. Perform any Technical Service Bulletins that may apply.

      Were there any problems found?

      Yes 

      No