John Deere 91.04 – ECU, CAB, EPC, or OIC: Foot Throttle Sensor Circuit Voltage Problem

The control unit measures a voltage below 0.3 volts at the signal input of the accelerator pedal potentiometer, indicating a short to ground, faulty sensor, poor wiring, or complete disconnection. This can lead to sluggish acceleration, poor throttle response, or the engine locking at idle.

• 5065M
• 5075M
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5095M
• 5095MH
• 5105M
• 5015ML
• 5E Series
• 5M Series
• 5045E
• 5055E
• 5065E
• 6M Series
• 6R Series
• 6000 Series
• 6230
• 6330
• 6430
• 7000 Series
• 7610
• 7710
• 7810
• 7720
• 7820
• 7920
• 8000 Series
• 8130
• 8230
• 8330
• 8430
• 8530
• 9000 Series
• 9230
• 9330
• 9430
• 9530
• 9630
• 204L
• 304L
• 244J
• 444J
• 544J
• 624J
• 644J
• G-III Skidders

1. 1

   Inspect the wiring harness associated with the accelerator pedal potentiometer for any signs of short circuits to ground, damaged insulation, rubbed-through areas, or exposed wires.

2. 2

   Inspect all connectors and terminals in the foot throttle circuit. Ensure connections are secure and clean. Repair or replace any pins that are loose, pushed back, or corroded.

3. 3

   Use a multimeter to test for ground faults in the wiring leading from the sensor to the control unit.

4. 4

   Use a diagnostic tool or a multimeter to test the accelerator pedal potentiometer functionality. Verify it is providing accurate voltage readings (it should not drop below 0.3V).

1. 1

   Prepare machine for service

   Turn off the machine, engage the parking brake, and disconnect the battery to prevent electrical surges while working with electronic components.

2. 2

   Locate the sensor

   Locate the foot throttle sensor / accelerator pedal potentiometer, which is typically mounted directly to the accelerator pedal assembly under the operator platform or cab floor.

3. 3

   Disconnect the harness

   Carefully unplug the wiring harness connector from the sensor.

4. 4

   Remove the faulty sensor

   Unbolt the mounting hardware securing the potentiometer to the pedal linkage or floor bracket and remove the old unit.

5. 5

   Install the new sensor

   Mount the direct-replacement sensor into position and secure it with the mounting hardware.

6. 6

   Reconnect system

   Plug the wiring harness back into the new sensor, ensuring the connector clicks and locks into place. Reconnect the battery.

7. 7

   Reset and test

   Turn the key on. Use the cab display or a diagnostic tool to clear the stored 000091.04 fault code. Start the engine and test the accelerator pedal response to ensure smooth operation and verify the code does not return. Note: Some machines may require a few minutes to relearn the new sensor's parameters.