Diagnostic Test

WARNING: This page is about a different car, the 2011 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.
2. With the scan tool, View 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 LINE HEATER RELAY
1. With the scan tool, Erase DTCs.
2. Turn the ignition off.
3. Replace the DEF Line Heater Relay with a known good relay.
4. Turn the ignition on.
5. With the scan tool, navigate to Actuator Tests and actuate the Line Heater Relay.
6. With the scan tool, View DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2.
  No
  - Repair complete.
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
CHECK THE (K475) DEF LINE HEATER RELAY SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE

Fig 1: Checking DEF Line Heater Relay Signal Circuit For An Open Or High Resistance
Courtesy of CHRYSLER LLC
1. Stop actuation of the Line Heater Relay.
2. Turn the ignition off.
3. Remove the DEF Line Heater Relay.
4. Disconnect the DEF Dosing Control Unit C2 harness connector.
5. Measure the resistance of the (K475) DEF Line Heater Relay Signal circuit between the Line Heater Relay, terminal 86, and the DEF Dosing Control Unit C2 harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 4.
  No
  - Repair the (K475) DEF Line Heater Relay Signal circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
CHECK THE (K429) DEF LINE HEATER RELAY CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE

Fig 2: Checking DEF Line Heater Relay Control Circuit For An Open Or High Resistance
Courtesy of CHRYSLER LLC
1. Measure the resistance of the (K429) DEF Line Heater Relay Control circuit between the Line Heater Relay, terminal 85, and the DEF Dosing Control Unit C2 harness connector.
  Is the resistance below 5.0 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 - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .
  No
  - Repair the (K429) DEF Line Heater Relay Control circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .