Why Does Preheat Light Flash After the Engine is Warm?
          

Symptoms
The preheat light is flashing after the engine is warmed up.

Situation or Problem
The ECU (engine control unit) uses this existing indicator light as it's own warning or trouble light.

Summary
If the preheat light is flashing any time other than at cold start up, the ECU is storing a code and the engine is possibly going into a protection mode. A protection mode will typically limit engine rpm depending on urgency of the problem. As an example, high coolant temperature or low engine oil pressure would limit engine rpm to low idle. Call your local dealer for diagnosis.

Affected Equipment
6120 Tractor       6220 Tractor    
6320 Tractor      6420 Tractor    
6520 Tractor       7220 Tractor    
7320 Tractor       7420 Tractor    

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