P203F

P203F-(DIESEL EXHAUST FLUID) REDUCTANT LEVEL TOO LOW
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation

The Diesel Exhaust Fluid (DEF) system holds a total of eight gallons of fluid. There are a series of three warning levels to indicate to the customer when the fluid is low or incorrect. The driver warning and inducement strategy for a low fluid condition is as follows: The first warning will occur when the tank level is at approximately three gallons. The customer will here a chime and get an EVIC message reading "LOW DEF REFILL SOON". The second warning level will occur when the tank level is at approximately two gallons. The customer will here a chime and get an EVIC message reading "REFILL DEF ENGINE WILL NOT RESTART IN XXX MILES". If the message is ignored until the tank is empty, the vehicle will not start. The customer will here a chime and get an EVIC message reading "REFILL DEF ENGINE WILL NOT START". The system will arrive at this level with approximately 0.7 gallon of fluid left in the tank. The vehicle will not start until a minimum of two and a half gallons of approved Diesel Exhaust Fluid is added to the tank.

- When Monitored:
Continuously with the ignition on.

- Set Condition:
The DEF Dosing Control Unit detects that the DEF Tank is low.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
ACTIVE DTC
1. Turn the ignition on, engine not running.
2. With the scan tool check for active DTCs.

Is the DTC active?

Yes

- The DEF Tank is low. If the vehicle will not start due to the tank being empty, a minimum of two and a half gallons of approved Diesel Exhaust Fluid must be added for engine to be started.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Perform the INTERMITTENT CONDITION - 6.7L. Intermittent Condition Test