Toro 4540 Lawn Mower User Manual


 
Greensmaster 3320/3420Page 6 -- 56Electrical System
Reel Speed Potentiometer (Serial Number Below 312000000)
The reel speed potentiometer on Greensmaster TriFlex
Hybrid machines with serial number below 312000000
controls the cutting reel speed. The TEC controller uses
the potentiometer setting as an input to determine the
necessary CAN--bus output to the cutting reel motor
controllersfor correctcutting reelspeed. The reel speed
potentiometer is located under the operator seat (Fig.
67).
Testing
1. Park machine on level surface, lower cutting units,
stop engine, apply parking brake and remove key from
ignition switch.
2. Raise and support operator seat to gain access to
reel speed potentiometer.
3. Carefully unplug wire harness connector from reel
speed potentiometer.
4. Slide knob from shaft of potentiometer (Fig. 68). Re-
move screws that secure potentiometer to machine and
remove potentiometer from machine for testing.
5. Using a multimeter, measure resistances between
potentiometer terminals as follows (Fig. 69):
A. Verify that resistance between terminals B and C
is approximately 5000 ohms. Record measured re-
sistance.
B. Measure resistance between terminals A and C
and then measure resistance between terminals A
and B .Record these resistances. Thetotal of the two
measured resistances should be approximately
5000 ohms.
C. Rotate the reel speed potentiometer to other set-
tings and repeat step 6. The total of the two resist-
ances should consistently be approximately 5000
ohms.
D. If measured resistances are incorrect, replace
reel speed potentiometer.
6. After testing is completed, secure potentiometer to
machine bracket and slide knob onto potentiometer
shaft. Secure wire harness connector to potentiometer.
Lower and secure seat.
Figure 67
2
1
1. Fuse block 2. Potentiometer
1. Potentiometer
2. Knob
3. Screw (2 used)
4. Bracket
5. Backlap switch
Figure 68
4
1
2
5
3
1. Terminal A
2. Terminal B
3. Terminal C
Figure 69
1
2
3