Think Leak Detection Information

Electrical Leakage Detection
Circuit Description and Operation
The electrical leakage detection circuit measures current flow from the battery pack to the
vehicle frame. The battery pack is electrically isolated from the vehicle frame. There are four
system components that ground to the frame: headlamps, chassis connector, wiper motor and the
park brake switch. The chassis connector circuit is between the instrument cluster gauge and an
eyelet that is connected to the frame on the opposite side of the DC/DC converter 1 (standard).
An OP AMP inside the instrument cluster gauge converts voltage to amperage from any place
where leakage is detected. Any current above 0.1mA will set the electrical leakage indicator.
Any part of the 72 volt harness has the potential for leakage detection. The 12 volt harness has
the potential for leakage detection at the accelerator potentiometer and the motor
tachometer/speed sensor. Vehicles equipped with the optional power point will have a DC/DC
converter 2 (optional). The DC/DC converter 2 (optional) also has the potential for leakage
detection.


The following components and harnesses are to be checked for electrical leakage in this
procedure:

  • Contactor coil
  • Instrument cluster gauge
  • Motor controller
  • DC/DC converter 1 (standard)
  • DC/DC converter 2 (optional)
  • Motor
  • Motor tachometer/speed sensor
  • Accelerator potentiometer
  • Charger
  • 72 volt harness

Required Tools
High Voltage Insulated Gloves 100-F036 or equivalent
Face Shield 100-F035 or equivalent

Guidelines to diagnose electrical leakage:

  1. Service disconnect switch must be in the ON position to observe the electrical leakage indicator located on the face of the instrument cluster gauge.
  2. Before disconnecting any component, you must first place the service disconnect switch in the OFF position.
  3. Check all connectors and related wiring for partially seated terminals, connectors not mating properly and for dirt, moisture or corrosion. For proper contact, terminal(s) must be free of all foreign material. Wait at least 2 minutes after all debris has been cleared so that the instrument cluster gauge has enough time to detect leakage.
  4. Make sure the vehicle is thoroughly dry before attempting electrical leakage diagnosis.

 

Electrical leakage may be detected if certain electrical connectors are exposed to moisture
due to rain or washing of the vehicle. This will cause the electrical leakage indicator in the
instrument cluster gauge to be set.


Electrical Leakage Diagnosis
WARNING:
THE BATTERY PACK ASSEMBLY CAN DELIVER IN EXCESS OF 72 VOLTS OF DC
POWER. IMPROPER HANDLING OF THE BATTERY PACK CAN RESULT IN
INJURY OR FATALITY. ONLY AUTHORIZED PERSONNEL TRAINED TO WORK
WITH BATTERY PACK COMPONENTS ARE PERMITTED TO HANDLE THE
BATTERIES.


WARNING:
THE BATTERY PACK CONTAINS HIGH-VOLTAGE COMPONENTS AND WIRING.
HIGH-VOLTAGE INSULATED SAFETY GLOVES AND FACE SHIELD MUST BE
WORN WHEN PERFORMING THE FOLLOWING STEPS. FAILURE TO FOLLOW
THIS WARNING MAY RESULT IN SEVERE PERSONAL INJURY OR DEATH.
BATTERY PACK ASSEMBLY CAN DELIVER IN EXCESS OF 72 VOLTS OF DC
POWER. IMPROPER HANDLING OF THE BATTERY PACK CAN RESULT IN
INJURY OR FATALITY. ONLY AUTHORIZED PERSONNEL TRAINED TO WORK
WITH BATTERY PACK COMPONENTS ARE PERMITTED TO HANDLE THE
BATTERIES.


Step Action Connector End
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1. Did you read the Circuit Description and Operation?
Yes - GO to Step 2.
No - REFER to Circuit Description and Operation in this
section.
2. 

  1. Place the service disconnect switch in the OFF position.
  2. Disconnect the chassis connector.
  3. Place the service disconnect switch in the ON position.
  4. Set the park brake.
  5. Place the drive mode selector switch in the Reverse, Turf or Drive mode and wait 10 seconds.
  6. Observe the instrument cluster gauge.

Does the electrical leakage indicator display?
Yes – INSTALL a new instrument cluster gauge. REFER to Instrument Cluster Gauge in this section. OPERATE the
system to verify the repair.
No – RECONNECT the chassis connector. GO to Step 3.


3. Drive the vehicle while observing the instrument cluster gauge.


Does the electrical leakage indicator display only after heavy acceleration or high motor load?
Yes – INSTALL a new motor. REFER to Motor in the Powertrain section. OPERATE the system to verify the repair.
No – GO to Step 4.

4.

  1. Place the service disconnect switch in the OFF position.
  2. Disconnect the motor harness connectors.
  3. Place the service disconnect switch in the ON position.
  4. Set the park brake.
  5. Place the drive mode selector switch in the Reverse, Turf or Drive mode and wait 10 seconds.
  6. Observe the instrument cluster gauge.


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Does the electrical leakage indicator display?
Yes – GO to Step 5.
No – INSTALL a new motor. REFER to Motor in the Powertrain section. OPERATE the system to verify the
repair.


5.

  1. Place the service disconnect switch in the OFF position.
  2. Reconnect the motor harness connectors.
  3. Disconnect the motor controller harness connector.
  4. Place the service disconnect switch in the ON position.
  5. Set the park brake.
  6. Place the drive mode selector switch in the Reverse, Turf or Drive mode and wait 10 seconds.
  7. Observe the instrument cluster gauge.

Does the electrical leakage indicator display?
Yes – GO to Step 6.
No – INSTALL a new motor controller. REFER to Motor Controller in the Powertrain section. OPERATE the system to verify the repair.

6.

  1. Place the service disconnect switch in the OFF position.
  2. Reconnect the motor controller harness connector.
  3. Disconnect the DC/DC converter 1 (standard).
  4. Place the service disconnect switch in the ON position.
  5. Place the drive mode selector switch in the Reverse, Turf or Drive position and wait 10 seconds.
  6. Observe the instrument cluster gauge.


Is the electrical leakage indicator displayed?


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Yes – If vehicle is equipped with DC/DC converter 2 (optional), GO to Step 7.
If the vehicle is not equipped with DC/DC converter 2 (optional), GO to Step 8.
No – INSTALL a new DC/DC converter 1 (standard). REFER to DC/DC Converter 1 (Standard) in this section. OPERATE the system to verify the repair.

7.

  1. Place the service disconnect switch in the OFF position.
  2. Reconnect the DC/DC converter 1 (standard) harness connector.
  3. Disconnect the DC/DC converter 2 (optional).
  4. Place the service disconnect switch in the ON position.
  5. Place the drive mode selector switch in the Reverse, Turf or Drive position and wait 10 seconds.
  6. Observe the instrument cluster gauge.


Is the electrical leakage indicator displayed?
Yes - GO to Step 8.
No - INSTALL a new DC/DC converter 2 (optional). REFER to DC/DC Converter (Optional) in this section. OPERATE the system to verify the repair.

8.

  1. Place the service disconnect switch in the OFF position.
  2. Reconnect the DC/DC converter 2 (optional) (if equipped) and the DC/DC converter 1 (standard) harness connectors.
  3. Disconnect the charger harness connector.
  4. Place the service disconnect switch in the ON position.
  5. Place the drive mode selector switch in the Reverse, Turf or Drive position and wait 10 seconds.


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6. Observe the instrument cluster gauge.


Is the electrical leakage indicator displayed?
Yes - GO to Step 9.
No - INSTALL a new charger. REFER to Charger in this section. OPERATE the system to verify the repair.


9.

  1. Place the service disconnect switch in the OFF position.
  2. Reconnect the charger harness connector.
  3. Disconnect the accelerator potentiometer harness connector.
  4. Place the service disconnect switch in the ON position.
  5. Place the drive mode selector switch in the Reverse, Turf or Drive position and wait 10 seconds.
  6. Observe the instrument cluster gauge.

Is the electrical leakage indicator displayed?
Yes – GO to Step 10.
No – INSTALL a new accelerator potentiometer. REFER to Accelerator Potentiometer in the Powertrain section. OPERATE the system to verify the repair.

10.

  1. Place the service disconnect switch in the OFF position.
  2. Reconnect the accelerator potentiometer harness connector.
  3. Disconnect the motor tachometer/speed sensor harness connector.
  4. Place the service disconnect switch in the ON position.
  5. Place the drive mode selector switch in the Reverse, Turf or Drive position and wait 10 seconds.
  6. Observe the instrument cluster gauge.

Is the electrical leakage indicator displayed?
Yes - GO to Step 11.


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No - INSTALL a new motor tachometer/speed sensor.
REFER to Motor Tachometer/Speed Sensor in the
Powertrain section. OPERATE the system to verify
the repair.


11.

  1. Place the service disconnect switch in the OFF position.
  2. Reconnect the motor tachometer/speed sensor harness connector.
  3. Disconnect the contactor coil harness connectors.
  4. Place the service disconnect switch in the ON position.
  5. Place the drive mode selector switch in the Reverse, Turf or Drive position and wait 10 seconds.
  6. Observe the instrument cluster gauge.

Is the electrical leakage indicator displayed?
Yes – GO to Step 12.
No - INSTALL a new contactor coil. REFER to Contactor in this section. OPERATE the system to verify the repair.

12.

  1. Place the service disconnect switch in the OFFposition.
  2. Reconnect the motor tachometer/speed sensorharness connector.
  3. Clean battery cases and battery compartment to make sure there is no dirt, moisture or corrosion buildup that could create an electrical leak path.
  4. Place the service disconnect switch in the ON position.
  5. Place the drive mode selector switch in the Reverse, Turf or Drive position and wait 10 seconds.
  6. Observe the instrument cluster gauge.

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Is the electrical leakage indicator displayed?
Yes – INSTALL a new 72 volt harness. REFER to Wiring Harnesses in this section. OPERATE the system to verify the repair.
No – GO to Step 13.


13.

Connect the positive lead of a DVOM to the positive terminal of the first battery (from the negative end of the battery pack). Connect the negative lead of the DVOM to the vehicle chassis.


Does the DVOM display negative voltage?
Yes – REMOVE and CLEAN the battery with a baking
soda solution. REINSTALL the battery and RETEST to verify the repair.
No – MOVE the positive lead of the DVOM to the positive terminal of the next battery of the battery pack. CHECK each battery until a negative voltage is displayed on the DVOM. REMOVE and CLEAN the battery that displays a negative voltage. RETEST to verify the repair.