Service Manual

ManualsBrandsToro ManualsVehiclesWorkman GTX Electric Utility Vehicle

Workman GTX Electric Page 3A -- 23 Electrical System

Traction Motor

The traction motor stator winding, thermistor (tempera-

ture) and encoder (speed sensor) can be tested with the

motor attached to the transaxle. Test connection points

for the traction motor are shown in Fig. 33.

If a traction motor component is faulty, there should like-

ly be a fault code displayed on the controller LED and the

status indicator light. Before disconnecting electrical

connections on the motor, check for existing fault codes

that suggest a problem with the motor. See Controller in

this section for additional information regarding faults.

Before disconnecting any electrical connections from

thetractionmotor,openthevehiclebatterycircuitbydis-

connecting the conductors between the battery pack

and vehicle components (see Opening Battery Circuit in

the General Information section of this chapter). When

installing cables to motor terminals, torque jam nuts at

terminals from 72 to 88 in--lb (8 to 9 N--m) (Fig. 37). Ap-

ply Toro battery terminal protector (see Special Tools) to

motor connections after tightening nuts.

RefertoTractionMotorandTractionMotorServicein

the Service and Repairs section of this chapter for trac-

tion motor removal, installation, disassembly and as-

sembly information.

Stator Winding Testing

Use a multimeter to measure resistance (ohms) be-

tween motor terminals (U, V and W). There should be

very low (not zero) resistance between pairs of termi-

nals (U and V, V and W and U and W). Also, measure

resistance between each t erminal and the motor drive

end bracket. There should be infinite resistance be-

tween each terminal and the drive end bracket.

If resistance between terminals is either very high or ze-

ro, the stator is damaged. The stator is also faulty if re-

sistance between any terminal and the drive end

bracket is not infinite. If stator is damaged, replacement

of the traction motor is necessary.

Thermistor (Thermally Sensitive Resistor) Testing

Use a multimeter to measure resistance (ohms) be-

tween the pins in the thermis tor connector. The mea-

sured resistance at 77F (25

) ( motor temperature)

should be approximately 600 ohms. If resistance test-

ing determines a short circuit (low resistance) or an

open circuit (infinite resistance), the thermistor or ther-

mistor wiring is damaged and the motor must be re-

placed. The thermistor is an integral component of the

traction motor stator.

Encoder (Speed Sensor) Testing

If encoder problems exist, the vehicle controller should

determine that a problem exists and a fault code should

be displayed on the controller LED and the status indica-

tor light. See Controller in this section for additional infor-

mation regarding encoder faults.

NOTE: If a traction motor armature problem exists in

the motor (e.g. worn bearing in rear end bracket, miss-

ing retaining ring on rear of armature shaft, loose or

damaged tone ring on armature), an encoder fault could

be generated due to the armature issue.

1. Thermistor connector

2. Terminal U

3. Terminal V

4. Terminal W

5. Drive end bracket

6. Encoder

7. Armature tone ring

Figure 33

Electrical

System