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 INTERMITTENT CONDITION
1. Turn the ignition on.
2. With the scan tool, clear all DTCs.
3. 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 .
ATTEMPT TO SET THE OPPOSITE DTC
1. Turn the ignition off.
2. Disconnect the Fuel Pump Module C1 harness connector.
3. Turn the ignition on.
4. With the scan tool, read DTCs.
  Does the scan tool display DTC: B1006-13-FUEL LEVEL SENSOR - CIRCUIT OPEN?
  
  Yes
  - Replace the Fuel Level Sending Unit in accordance with the Service Information. Refer to MODULE, FUEL PUMP, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY CONTROL MODULE (BCM) - BODY VERIFICATION TEST - 500 - EXCEPT ELECTRIC .
  No
  - Go To 3
CHECK THE (N4) FUEL LEVEL SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the BCM C2 harness connector.
3. Measure the resistance between ground and the (N4) Fuel Level Sensor Signal circuit at the Fuel Pump Module C1 harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the short to ground in the (N4) Fuel Level Sensor Signal circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY CONTROL MODULE (BCM) - BODY VERIFICATION TEST - 500 - EXCEPT ELECTRIC .
CHECK THE (N4) FUEL LEVEL SENSOR SIGNAL CIRCUIT FOR A SHORT TO THE (G109) FUEL LEVEL SENSE RETURN CIRCUIT
1. Measure the resistance between the (G109) Fuel Level Sense Return circuit and the (N4) Fuel Level Sensor Signal circuit at the Fuel Pump Module C1 harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 5
  No
  - Repair the short between the (G109) Fuel Level Sense Return circuit and the (N4) Fuel Level Sensor Signal circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY CONTROL MODULE (BCM) - BODY VERIFICATION TEST - 500 - EXCEPT ELECTRIC .
BODY CONTROL MODULE (BCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Pump Module and the BCM.
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 Fuel Pump Module and the BCM harness connectors.
4. Perform any Technical Service Bulletins (TSB)s that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the BODY VERIFICATION TEST. Refer to BODY CONTROL MODULE (BCM) - BODY VERIFICATION TEST - 500 - EXCEPT ELECTRIC .
  No
  - Replace the BCM in accordance with the Service Information. Refer to MODULE, BODY CONTROL, REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY CONTROL MODULE (BCM) - BODY VERIFICATION TEST - 500 - EXCEPT ELECTRIC .