Diagnostic Test

WARNING: This page is about a different car, the 2015 RAM 3500 HD and 2015 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

ACTIVE DTC
NOTE:
If the P204C or P204D DTCs are present along with this DTC, diagnose and repair those DTCs before continuing.
1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 75 seconds.
5. Turn the ignition on, run the engine to operating temperature
6. Test drive the vehicle under normal operating conditions to induce the DEF system.
7. 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 INTERMITTENT CONDITION - 6.7L .
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 POWERTRAIN VERIFICATION TEST - 6.7L .
  No
  - Go To 3
CHECK THE DEF TANK HARNESS
1. Turn ignition off.
2. Disconnect the DEF Dosing Control Unit C2 harness connector.
3. Measure the resistance between the DEF Supply Pump Phase circuits (A, B, and C) at the DEF Dosing Control Unit C2 harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 4
  No
  - Replace the DEF Tank Harness in accordance with the service information.
    Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
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 5
  No
  - Replace the DEF Tank Harness in accordance with the service information.
    Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
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 6
  No
  - Replace the DEF Tank Harness in accordance with the service information.
    Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
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 7
  No
  - Replace the DEF Tank Harness in accordance with the service information.
    Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
CHECK THE DIESEL EXHAUST FLUID
1. Turn the ignition off.
2. Collect a sample of diesel exhaust fluid from the system.
3. Visually inspect the fluid for signs of contamination or debris.
4. To test for hydrocarbons in the DEF tank use Hydroscopic test paper (223-44-863) available through MoparEssentialTools.com. Then, ENTER EQUIPMENT CATALOG. Or call (855)-298-2687. The test strip must come in contact with the DEF fluid in the tank in order to get a valid reading for hydrocarbons present in tank.
5. Remove the test paper from the package and inspect for color consistency. If the color is not consistent replace strip.
6. Disconnect the DEF fill pipe from tank and try to get a sample or remove the DEF tank.
7. Place the test paper directly into the DEF fluid in the tank. If the light blue paper turns dark blue, that is an indication that oil or hydrocarbon contamination is present.
  Is the Diesel Exhaust Fluid (DEF) free of debris, hydrocarbons, or other contamination?
  
  Yes
  - Go To 8
  No
  - If the DEF fails the Hydroscopic test paper test or shows signs of other contaminants: Drain the Diesel Exhaust Fluid (DEF). Replace the DEF Tank, DEF Supply Pump Assembly, DEF Injector, DEF Supply Tube, DEF Filler Tube, and DEF Filler Cap in accordance with the service information.
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
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 POWERTRAIN VERIFICATION TEST - 6.7L .
  No
  - Replace the DEF Tank Harness in accordance with the service information.
    Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .