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:
If there are any 5-Volt Supply DTCs present, perform the diagnostics for those DTCs before continuing with this one.
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 .
CHECK THE (K926) CRANKCASE PRESSURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the Crankcase Pressure Sensor harness connector.
3. Disconnect the PCM C2 harness connector.
4. Check for continuity between ground and the (K926) Crankcase Pressure Sensor Signal circuit at the Crankcase Pressure Sensor harness connector.
  Is there continuity between ground and the (K926) Crankcase Pressure Sensor Signal circuit?
  
  Yes
  - Repair the (K926) Crankcase Pressure Sensor Signal circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
  No
  - Go To 3
CHECK THE (K926) CRANKCASE PRESSURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO THE (K915) SENSOR GROUND
1. Check for continuity between the (K926) Crankcase Pressure Sensor Signal circuit and the (K915) Sensor Ground circuit at the Crankcase Pressure Sensor harness connector.
  Is there continuity between the (K926) Crankcase Pressure Sensor Signal circuit and the (K915) Sensor Ground circuit?
  
  Yes
  - Repair the short between the (K926) Crankcase Pressure Sensor Signal circuit and the (K915) Sensor Ground circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
  No
  - Go To 4
CHECK THE (K926) CRANKCASE PRESSURE SENSOR SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Measure the resistance of the (K926) Crankcase Pressure Sensor Signal circuit between the Crankcase Pressure Sensor harness connector and the PCM C2 harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 5
  No
  - Repair the (K926) Crankcase Pressure Sensor Signal circuit for an open/high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
CRANKCASE PRESSURE SENSOR
1. Reconnect the PCM C2 harness connector.
2. Connect a jumper between the (K926) Crankcase Pressure Sensor Signal circuit and the (K860) 5-Volt Supply circuit.
3. Turn the ignition on.
  NOTE:
  The scan tool should display the P051D-CRANKCASE PRESSURE SENSOR CIRCUIT HIGH DTC as active or pending with the jumper in place.
4. With the scan tool, read DTCs.
  Does the DTC display as described above?
  
  Yes
  - Replace the Crankcase Pressure Sensor in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
  No
  - Go To 6
POWERTRAIN CONTROL MODULE
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Crankcase Pressure Sensor 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.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Service Bulletins that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
  No
  - Replace the Powertrain Control Module in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .