CONTROL ASSEM. 7N5581 - Caterpillar

Illustration 1 g00392624
The start relay magnetic switch is an output of the Power Train/Chassis Electronic Control Module (ECM). The start relay magnetic switch connects to connector contact J2-7. The start relay magnetic switch turns the start solenoid on and off. The start solenoid then controls the starting motor. After the operator turns the key start switch to the START position and the Power Train/Chassis ECM decides that all starting conditions are satisfied. The ECM will then activate the start relay magnetic switch with a +battery signal.The Power Train/Chassis ECM activates the relay when three conditions have been met.
The transmission is in the NEUTRAL position.
The parking brake is engaged.
The engine speed is zero.The start relay magnetic switch has two terminals and a connector with two contacts. The connector contact 1 of the start relay magnetic switch receives the +battery signal from J2-7 of the Power Train/Chassis ECM. The connector contact 2 of the start relay magnetic switch is connected to the solenoid return of the Power Train/Chassis ECM J1-60. One start relay magnetic switch terminal connects to a +battery source of the machine electrical system. The other start relay magnetic switch terminal connects to the start solenoid.The Power Train/Chassis ECM records diagnostic codes that occur with the start relay magnetic switch as a CID 0444.