DRIVE AR-FINAL 3724564 - Caterpillar

the key start switch is turned to the START position, the Power Train ECM will switch the starter relay ON provided the following conditions are true:
The armrest is in the Up position.
System voltage is less than 36 DCV.
The engine speed is 0 rpm.
The key override is off.
There are no diagnostic codes for the Armrest Position Switch or the Service Brake Pedal Limit Switch.After the start relay output is enabled, the starter relay will be turned off when any of the following conditions are true:
The key is not in the crank position.
Engine speed is greater than 400 rpm.
System voltage is greater than 36 DCV.
The armrest is in the Down position (and no faults detected).
There are diagnostic codes for the Armrest Position Switch or the Service Brake Pedal Limit Switch.Note: The key switch override is set when the starter relay is disabled because the engine speed has reached 400 rpm. The key switch override is reset when the key is turned to the Off position. The key switch override is an electronic means of preventing cranking with the engine already running. This is in the event that the manual keyswitch lock is bypassed or inoperable.