Diagnostic Test

WARNING: This page is about a different car, the 2013 RAM 3500 HD and 2013 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

ACTIVE DTC
NOTE:
If the P21CA or P21CB DTCs are present along with this DTC, diagnose and repair those DTCs before continuing.
1. Ignition on, engine not running.
2. With the scan tool check for active DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION - 6.7L diagnostic procedure. Refer to STANDARD PROCEDURE .
CHECK THE DEF SUPPLY PUMP ASSEMBLY
1. Turn the ignition off.
2. Disconnect the DEF Supply Pump Assembly harness connector.
3. Turn the ignition on, engine not running.
4. With the scan tool, View DTCs.
  NOTE:
  Other DTCs will also set from unplugging the DEF Pump Assembly. Ignore any other DTCs that do not pertain to the DEF Pressure Sensor.
  
  Did DTC P204A change to stored after with the connector unplugged?
  
  Yes
  - Replace the DEF Supply Pump Assembly in accordance with the service information. Refer to ASSEMBLY, DIESEL EXHAUST FLUID PUMP, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
  No
  - Go To 3
CHECK FOR THE DEF PRESSURE SENSOR 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
1. Turn ignition off.
2. Disconnect the DEF Dosing Control Unit C2 harness connector.
3. Measure the resistance between ground and the DEF Pressure Sensor 5-Volt Supply circuit at the DEF Dosing Control Unit C2 harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the DEF Pressure Sensor 5-Volt Supply circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
CHECK FOR THE DEF LEVEL SENSOR 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
1. Turn ignition off.
2. Disconnect the DEF Dosing Control Unit C2 harness connector.
3. Measure the resistance between ground and the DEF Level Sensor 5-Volt Supply circuit at the DEF Dosing Control Unit C2 harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 5
  No
  - Repair the DEF Level Sensor 5-Volt Supply circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
CHECK FOR THE DEF PRESSURE SENSOR 5-VOLT SUPPLY CIRCUIT SHORTED TO ANOTHER CIRCUIT
1. Turn ignition off.
2. Disconnect the DEF Dosing Control Unit C2 harness connector.
3. Measure the resistance between the DEF Pressure Sensor 5-Volt Supply circuit and all other circuits at the DEF Dosing Control Unit C2 harness connector.
  Is the resistance above 10k Ohms between the DEF Pressure Sensor 5-Volt Supply circuit and all other circuits?
  
  Yes
  - Go To 6
  No
  - Repair the DEF Pressure Sensor 5-Volt Supply circuit for a short to the circuit that measured below 10k Ohms.
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
CHECK FOR THE DEF LEVEL SENSOR 5-VOLT SUPPLY CIRCUIT SHORTED TO ANOTHER CIRCUIT
1. Turn ignition off.
2. Disconnect the DEF Dosing Control Unit C2 harness connector.
3. Measure the resistance between the DEF Level Sensor 5-Volt Supply circuit and all other circuits at the DEF Dosing Control Unit C2 harness connector.
  Is the resistance above 10k Ohms between the DEF Level Sensor 5-Volt Supply circuit and all other circuits?
  
  Yes
  - Replace the DEF Dosing Control Unit in accordance with the service information. Refer to UNIT, DIESEL EXHAUST FLUID DOSING CONTROL, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .
  No
  - Repair the DEF Level Sensor 5-Volt Supply circuit for a short to the circuit that measured below 10k Ohms.
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to STANDARD PROCEDURE .