Diagnostic Test

WARNING: This page is about a different car, the 2017 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

ACTIVE DTC
NOTE:
If DTC P21CB or P21CC are also active, diagnose and repair that DTC before continuing with this test procedure.
1. Turn the ignition on, engine not running.
2. Using the scan tool, actuate the DEF Line Heater or perform Tank Heater Override Test.
3. With the scan tool, View DTCs.
  Is the DTC Active?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION. Refer to INTERMITTENT CONDITION .
CHECK THE (F203) SCR MODULE HEATER SUPPLY CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT
1. Turn the ignition off for 90 seconds.
2. Disconnect the PDC C5 harness connector.
3. Disconnect the DEF Dosing Control Unit C1 harness connector.
4. Disconnect the PCM C2 harness connector.
5. Measure the resistance between the (F203) SCR Module Heater Supply circuit and all other circuits at the DEF Dosing Control Unit C1 harness connector.
  Is the resistance above 10k Ohms between the (F203) SCR Module Heater Supply circuit and all other circuits?
  
  Yes
  - Go To 3
  No
  - Repair the short between the (F203) SCR Module Heater Supply circuit and the circuit that measured below 10k Ohms.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE DEF DCU FOR PROPER OPERATION
1. Replace the DEF Dosing Control Unit in accordance with the Service Information.
2. Turn the ignition on, engine not running.
3. With the scan tool, erase DTCs.
4. Using the scan tool, actuate the DEF Line Heater or perform Tank Heater Override Test.
5. With the scan tool, View DTCs.
  Did the DTC return?
  
  Yes
  - Go To 4
  No
  - Replacing the DCU repaired the condition.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all PCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. 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.
5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
10. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .