Electrical/Control Systems

Main Power Relay

The main power relay (A, Fig. 536) is located inside the engine compartment.

Relay Testing

Machine Test

1.Have an assistant sit in the operator’s seat and turn the ignition switch to the ON/RUN position. An audible “click” should be heard from the main relay as it closes.

2.With the ignition switch still in the ON/RUN position, pull closed relays out of the power distribution module. An audible “click” should be heard if the circuit is activated when the relay opens as it is removed.

3.With the ignition switch still in the ON/RUN position, plug the removed relays back into the power distribution module. An audible “click” should be heard if the circuit is activated and the relay is energized.

Model 1750RT (Serial Number 131301 and Up)

Model 2100RT (Serial Number 280051 and Up)

4.Replace any relay that does not “click” open/ closed during this test.

Bench Test

1.Remove the relay from the machine.

2.Apply ground to terminal 85 (Fig. 537), and 12VDC to terminal 86. An audible “click” should be heard when the relay is energized.

3.With the relay energized, measure for continuity between terminals 30 and 87.

Model 1750RT (Serial Number 131300 and Before)

Model 2100RT (Serial Number 280050 and Before)

4.Replace any relay that does not have continuity between terminals 30 and 87 when the relay is energized.