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:
Diagnose and repair any 5-Volt Reference DTCs before continuing with this diagnostic procedure.
1. Turn the ignition on.
2. Start the engine and allow it to reach normal operating temperature.
  WARNING:
  When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.
3. With the scan tool, read DTCs and record on the repair order.
  Is the DTC active or pending?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT DTC diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK FOR HIGH RESISTANCE IN THE (K37) BOOST PRESSURE SENSOR SIGNAL CIRCUIT
1. Turn the ignition off.
2. Disconnect the Boost Pressure Sensor harness connector.
3. Disconnect the PCM C2 harness connector.
4. Measure the resistance of the (K37) Boost Pressure Sensor Signal circuit between the MAP Sensor harness connector and the PCM C2 harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 3
  No
  - Repair the (K37) Boost Pressure Sensor Signal circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
CHECK FOR HIGH RESISTANCE IN THE (K900) SENSOR GROUND CIRCUIT
1. Measure the resistance of the (K900) Sensor Ground circuit between the Boost Pressure Sensor harness connector and the PCM C2 harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (K900) Sensor Ground circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
MAP SENSOR
1. Connect a jumper between the (F856) 5-Volt Supply circuit and the (K37) Boost Pressure Sensor Signal circuit at the TIP Sensor harness connector.
2. Turn the ignition on, engine not running.
3. With the scan tool, read DTCs and record on the repair order.
  NOTE:
  The scan tool should display a P0238-TURBO BOOST PRESSURE SENSOR CIRCUIT HIGH DTC as active or pending with the jumper in place.
4. Turn the ignition off.
5. Connect a jumper between the (K900) Sensor Ground circuit and the (K37) Boost Pressure Sensor Signal circuit at the TIP Sensor harness connector.
6. Turn the ignition on, engine not running.
7. With the scan tool, read DTCs.
  NOTE:
  The scan tool should display a P0237-TURBO BOOST PRESSURE SENSOR CIRCUIT LOW DTC as active or pending with the jumper in place.
  
  Did the DTCs display as described above?
  
  Yes
  - Replace the Boost Pressure Sensor in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
  No
  - Go To 5
CHECK RELATED PCM AND COMPONENT CONNECTIONS
1. Perform any Service Bulletins that apply.
2. Disconnect all PCM harness connectors.
3. Disconnect all related in-line harness connections (if equipped).
4. Disconnect the related component harness connectors.
5. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Check for spread terminals and verify proper terminal tension.
  Repair any conditions that are found.
6. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
7. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
9. With the scan tool, erase DTCs.
10. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
11. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Powertrain Control Module in accordance with the Service information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
  No
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST, 16V Turbo .
  - Test complete.