Diagnostic Test

WARNING: This page is about a different car, the 2012 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

ACTIVE DTC
1. Turn the ignition on for one minute, engine not running.
2. With the scan tool, navigate to Systems Tests and actuate the Diesel Exhaust Fluid Doser Pump Override Test.
3. With the scan tool, View DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2.
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION - 6.7L .
CHECK THE (K428) DEF INJECTOR SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE

Fig 1: Checking DEF Injector Signal Circuit For An Open/High Resistance
Courtesy of CHRYSLER GROUP, LLC
1. Stop actuation of the Diesel Exhaust Fluid Doser Pump Override Test.
2. Turn ignition off.
3. Disconnect the DEF Injector harness connector.
4. Disconnect the DEF Dosing Control Unit C1 harness connector.
5. Measure the resistance of the (K428) DEF Injector Signal circuit between the Diesel Exhaust Fluid Injector harness connector and the DEF Dosing Control Unit C1 harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 3.
  No
  - Repair the (K428) DEF Injector Signal circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
CHECK THE (K426) DEF INJECTOR RETURN CIRCUIT FOR AN OPEN/HIGH RESISTANCE

Fig 2: Checking DEF Injector Return Circuit For An Open/High Resistance
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance of the (K426) DEF Injector Return circuit between the Diesel Exhaust Fluid Injector harness connector and the DEF Dosing Control Unit C1 harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 4.
  No
  - Repair the (K426) DEF Injector Return circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
CHECK THE (K428) DEF INJECTOR SIGNAL CIRCUIT FOR A SHORT TO GROUND

Fig 3: Checking DEF Injector Signal Circuit For A Short To Ground
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance between ground and the (K428) DEF Injector Signal circuit at the Diesel Exhaust Fluid Injector harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 5.
  No
  - Repair the (K428) DEF Injector Signal circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
CHECK THE (K426) DEF INJECTOR RETURN CIRCUIT FOR A SHORT TO GROUND

Fig 4: Checking DEF Injector Return Circuit For A Short To Ground
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance between ground and the (K426) DEF Injector Return circuit at the Diesel Exhaust Fluid Injector harness connector.
  Is the resistance above 10k Ohms?
  
  Yes
  - Go To 6.
  No
  - Repair the (K426) DEF Injector Return circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
CHECK THE DEF INJECTOR
1. Measure the resistance across the terminals of the DEF Injector.
  NOTE:
  The resistance through the DEF Injector should be between 11.0 Ohms and 13.0 Ohms.
  
  Does the resistance measure between 11.0 Ohms and 13.0 Ohms?
  
  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. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
  No
  - Replace the DEF Injector in accordance with the Service Information. Refer to INJECTOR, DIESEL EXHAUST FLUID, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .