Electrical System; Relays; General - Toro Z Master Z597 Service Manual

ELECTRICAL

ELECTRICAL SYSTEM

General

Note: Interactive Electrical Troubleshooting CD,
Form 492-9143 is also available.
When turning the ignition switch clockwise to the RUN
position, the glow plug indicator light will come on. After
the glow plug indicator light goes out, turn the key to
the START position and start the mower. The "Low Oil
Pressure" alarm will sound a "pulse tone". Once the
engine starts and the oil pressure in the engine builds
the alarm will stop; this is normal.
Current flows from the ignition switch to the start relay
and on to the engine starter. At the same time, current
flows to the PTO switch, park brake switch, through the
two neutral motion control switches, then on to the fuel
solenoid and energizes the start relay and glow plug
relay.

RELAYS

Purpose
There are 4 relays.
1. Start Relay
2. Glow Plug Relay
3. Oil Pressure Relay
4. Alternator Relay.
1. Start Relay: Once the safety connections are met,
6
the relay will activate completing the circuit to the
starter solenoid.
2. Glow Plug Relay: Once the safety connections are
met, the relay will activate and provide current to the
glow plugs and Oil Pressure Relay.
3. Oil Pressure Relay: During the time the glow plug
relay is activated the oil pressure relay opens the
warning buzzer ground circuit.
4. Alternator Relay: The alternator relay completes
the audible alarm ground circuit if the alternator is
not charging.
6-2
Location
The alternator and the oil pressure relays are located
behind the engine access panel on the left side (Fig.
341).
B
A
Fig 341
A. Oil Pressure Relay
The glow plug and the start relay are located under the
seat area, behind the battery (Fig. 342).
D
C
Fig 342
C. Start Relay
Z Master 597 Diesel Series Service Manual
DSC-2515
B. Alternator Relay
DSC-2516
D. Glow Plug Relay