DERATE WARNING
UnclassifiedFuel
What This Code Means
Derate warning; NOx fault; DEF quality alert; Injector fouling; Hard starting; Filter clogging; Power loss; Excessive smoke under load; Engine fails to start; Slow crank; Failed to start
Possible Causes
- •DEF system failure
- •SCR catalyst failure
- •Fuel quality degradation
- •Turbocharger failure
- •Battery failure
- •DEF system (SCR catalyst) failure
- •Fuel quality / degradation
- •Injector fouling
- •Filter clogging
Related Rehlko Fault Codes
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