Diagnostic Test

WARNING: This page is about a different car, the 2013 RAM 2500 HD and 2012 RAM Pickup. However, it is still accessible from the selected car via links, so may be relevant.

ACTIVE DTC
NOTE:
Diagnose and repair any system voltage or sensor reference DTCs before continuing with this test.
1. Turn the ignition on.
2. With the scan tool, view DTCs.
  Is the DTC active
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to STANDARD PROCEDURE .
CHECK THE (N70) CNG TANK PRESSURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the CNG Tank Pressure Sensor harness connector.
3. Disconnect the PCM C1 harness connector.
4. Measure the resistance between ground and the (N70) CNG Tank Pressure Sensor Signal circuit at the CNG Tank Pressure Sensor harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 3
  No
  - Repair the (N70) CNG Tank Pressure Sensor Signal circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK FOR THE (N70) CNG TANK PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO THE (N10) SENSOR RETURN CIRCUIT
1. Measure the resistance between the (N70) CNG Tank Pressure Sensor Signal circuit and the (N10) Sensor Return circuit at the CNG Tank Pressure Sensor harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the short between the (N70) CNG Tank Pressure Sensor Signal circuit and the (N10) Sensor Return circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CNG TANK PRESSURE SENSOR
1. Turn the ignition off.
2. Reconnect the PCM C1 harness connector.
3. Connect a jumper between the (N8) ESIM 5-Volt Supply circuit and the (N70) CNG Tank Pressure Sensor Signal circuit at the CNG Tank Pressure Sensor harness connector.
  NOTE:
  Take care not to damage or spread the terminals.
4. Turn the ignition on.
5. With the scan tool, view DTCs.
  NOTE:
  The P01A1-ALTERNATIVE FUEL TANK PRESSURE SENSOR CIRCUIT HIGH DTC should become active or pending with the jumper in place.
  
  Does the DTC set as described above?
  
  Yes
  - Replace the CNG Tank Pressure Sensor in accordance with the service information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Go To 5
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the CNG Rail Tank 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 Technical Service Bulletins that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Replace and program the Powertrain Control Module (PCM) in accordance with the service information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to STANDARD PROCEDURE .