Diagnostic Test

WARNING: This page is about a different car, the 2015 Fiat 500. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
NOTE:
Low battery voltage can cause excessive current draw in very hot and cold ambient temperatures. Make sure the battery can pass a load test before continuing. Review Freeze Frame information to determine the ambient temperature when the DTC set.
1. Turn the ignition on.
2. With the scan tool, read DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
    NOTE:
    If this DTC sets intermittently, it is possible that the controller is overheating in extremely hot temperatures. This is considered a normal protection operation. No repair is necessary.
CHECK THE (K447) ETC MOTOR (+) CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Throttle Body harness connector.
3. Disconnect the PCM C2 harness connector.
4. Measure the resistance of the (K447) ETC Motor (+) circuit between the Throttle Body harness connector and the PCM C2 harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 3
  No
  - Repair the (K447) ETC Motor (+) circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE (K448) ETC MOTOR (-) CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K448) ETC Motor (-) circuit from the Throttle Body harness connector to the PCM C2 harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (K448) ETC Motor (-) circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK FOR THE ETC MOTOR CIRCUITS SHORTED TO 12 VOLTS
1. Reconnect the PCM C2 harness connector.
2. Turn the ignition on.
3. With the scan tool, actuate the Throttle Follower Test.
4. Slowly press and release the Accelerator Pedal while monitoring the voltage.
5. Measure the voltage between ground and the (K447) ETC Motor (+) circuit at the Throttle Body harness connector.
6. Measure the voltage between ground and the (K448) ETC Motor (-) circuit at the Throttle Body harness connector.
  NOTE:
  The voltage reading should change as the valve position is changed. A reading that stays at 12 volts would indicate a short to voltage.
  
  Is the voltage reading steady at 12 volts?
  
  Yes
  - Repair the (K447) ETC Motor (+) circuit or (K448) ETC Motor (-) circuit for a short to voltage.
    NOTE:
    A short to voltage on the motor circuits can damage the internal H-Bridge driver of the PCM and cause it to be open. After repairing the short to voltage, verify that the PCM was not damaged.
    
    Go To 5
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
THROTTLE BODY
1. With the scan tool, actuate the Throttle Follower Test.
2. Slowly press and release the Accelerator Pedal while monitoring the voltage.
  Is the voltage changing as the Throttle Body Valve position changes?
  
  Yes
  - If a short to voltage has been repaired on either of the ETC Motor circuits in the previous step, repair is complete. If not, replace the Throttle Body Assembly. Refer to THROTTLE BODY, REMOVAL . Disconnect the Battery when replacing the Throttle Body Assembly. After installation is complete, use a scan tool and select the ETC RELEARN function.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 6
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Throttle Body and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Throttle Body and Powertrain Control Module connectors.
4. Perform any Service Bulletins that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL and PROGRAM THE PCM (POWERTRAIN CONTROL MODULE) .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .