The thawing of the SCR system parts is too slow.
1. Use the diagnostic tool to run the SCR thawing test. This test checks both the coolant circuit and any electrical heaters in the SCR system. 2. If a failure has been found and corrected, start the engine. When the reductant dosing unit temperature and the reductant tank temperature indicate that the system is thawed, the system is started and the fault codes will be inactivated. 3. If no fault is found in the thawing system, ensure that the system is thawed before proceeding with troubleshooting of any other DTCs
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
The reductant dosing system has been attempting to thaw the system for too long without being able to start
1. Reductant tank heater valve (V118) is blocked 2. Blocked engine coolant hoses to the SCR system 3. Blocked engine coolant pipes in the reductant pick-up unit 4. Broken electrical heaters in the reductant dosing system 5. Broken temperature sensor in the reductant pick-up unit (T116) 6. Engine coolant temperature is too low due to engine coolant circuit function failure 7. Other (non thawing related) faults causing the system to fail to start