22
Test Procedures
ELECTRICAL SYSTEM AND TESTING:
ELECTRIC VEHICLES
1
6
5
4
2
3
1. Purple/White Wire
2. White Wire
3. Yellow Wire
4. MCOR — Located On Passenger Side Frame Rail
5. Blue Wire
6. Green Wire
Figure 22-7
Test MCOR Voltage
3.
If reading is zero volts, check the purple/white wire continuity from the three-pin connector at the MCOR to the
24-pin connector at the speed controller. Check terminal positions in three-pin connector at the MCOR and the
24-pin connector. If all of the continuity readings are correct and the connectors are wired correctly, replace the
speed controller.
4.
With multimeter set to 20 volts DC, place the black (–) probe on battery no. 6 negative post and the red (+) probe
(with insulation-piercing probe) on the white wire (2) at a point close to the three-pin connector at the MCOR
. The reading should be approximately 4.65 volts.
5.
If reading is zero volts, check the white wire continuity from the three-pin connector at the MCOR to the 24-pin
connector at the speed controller. Check terminal positions in three-pin connector at the MCOR and the 24-pin
connector. If all of the continuity readings are correct and the connectors are wired correctly, replace the
speed controller.
6.
With multimeter set to 20 volts DC, place the black (–) probe on battery no. 6 negative post and the red (+) probe
(with insulation-piercing probe) on the yellow wire (3) at a point close to three-pin connector at the MCOR
. The reading should be approximately 0.32 volts with the pedal up. Slowly press the
accelerator pedal and note the readings on the multimeter. As the pedal is pressed, the reading should increase
until it reaches 4.65 volts when the pedal is fully pressed.
7.
If reading does not increase as the pedal is pressed, replace the MCOR.
8.
If the reading is not approximately 4.60 volts with the pedal fully pressed, the vehicle will not operate at rated
top speed. Check the MCOR resistance.
8.1. Disconnect the batteries and discharge the controller.
See Disconnecting the Batteries – Electric
Vehicles, Section 1, Page 1-4.
8.2. Disconnect the 24-pin connector at the speed controller.
8.3. Set a multimeter to 20k ohms. Connect the red (+) probe of the multimeter to the yellow wire at the MCOR
three-pin connector with an insulation piercing probe. Connect black (–) probe to the purple/white wire with
an insulation-piercing probe.
8.4. With the accelerator pedal fully up (not pressed), the multimeter should read approximately 1k ohms.
8.5. Slowly press the accelerator pedal while monitoring the multimeter. The resistance should rise as the
pedal is pressed. When the pedal is all the way to the floor, the multimeter should indicate between
5.67k ohms and 7.43k ohms.
Page 22-14
2007-2009 Turf 252, Carryall 252 and XRT 900 Maintenance and Service Manual
