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 DIAGNOSTIC TROUBLE CODE (DTC)
1. Turn the ignition on.
2. With the scan tool, read DTCs.
  Does the scan tool display this DTC as active?
  
  Yes
  - Go To 2
  No
  - Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
  - Perform the BODY VERIFICATION TEST. Refer to BODY CONTROL MODULE (BCM) - BODY VERIFICATION TEST - 500 - EXCEPT ELECTRIC .
CHECK EACH PARK ASSIST SENSOR FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect one Park Assist Sensor.
3. Turn the ignition on.
4. With the scan tool, read Park Assist Module DTCs. If this DTC is still active, repeat this procedure by disconnecting another Park Assist Sensor. However, if this DTC changes from active to stored, or if all sensors have been disconnected, proceed as follows:
  Does the scan tool still display this DTC as active?
  
  Yes
  - Go To 3
  No
  - Replace the Park Assist Sensor that caused this DTC to change from active to stored after disconnecting it in accordance with the Service Information. Refer to SENSOR, PARK ASSIST, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY CONTROL MODULE (BCM) - BODY VERIFICATION TEST - 500 - EXCEPT ELECTRIC .
CHECK THE PARK ASSIST SENSOR SUPPLY CIRCUIT FOR A SHORT TO GROUND
NOTE:
Perform this test with all Rear Park Assist Sensors disconnected.
1. Disconnect the Park Assist Module C2 harness connector.
2. Measure the resistance between ground and the Park Assist Sensor Supply circuit.
  Is the resistance below 10K Ohms?
  
  Yes
  - Repair the Park Assist Sensor Supply circuit for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to BODY CONTROL MODULE (BCM) - BODY VERIFICATION TEST - 500 - EXCEPT ELECTRIC .
  No
  - Replace the Park Assist Module in accordance with the Service Information. Refer to MODULE, PARK ASSIST, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY CONTROL MODULE (BCM) - BODY VERIFICATION TEST - 500 - EXCEPT ELECTRIC .