Case IH 3366 – Engine ECU (EDC - Electronic Diesel Control): Foot Pedal 2 - Signal Not Plausible Compared to Foot Pedal 1

The electronic accelerator pedal contains two redundant internal potentiometers (sensors) for safety. The control module constantly compares the voltage signals from both sensors. Code 3366 is triggered when the signal voltage from Foot Pedal Sensor 2 does not correctly correlate with the signal voltage from Foot Pedal Sensor 1, indicating a mismatch, a wiring issue, or a failing sensor track inside the pedal assembly.

• Case IH Magnum 235 - 340 (Series 4)
• Case IH Steiger series
• Case IH Maxxum series
• Case IH Puma series

1. 1

   Visual Inspection: Inspect the wiring harness and the electrical connector at the foot pedal. Look for corrosion, moisture, pushed-out pins, or chafed wires that could cause a short or open circuit.

2. 2

   Voltage Check: Verify that the pedal assembly is receiving the correct 5V reference voltage and has a solid ground from the Engine ECU.

3. 3

   Live Data Monitoring: Connect a diagnostic scan tool and monitor the live data for 'Foot Pedal 1' and 'Foot Pedal 2' voltages. Slowly depress the pedal from 0% to 100% travel. The two voltages should scale smoothly without any erratic jumps or dropouts. If one signal drops out or fails to track proportionally with the other, the internal pedal sensor is defective.

1. 1

   Disconnect battery

   Turn off the tractor, remove the key, and disconnect the battery ground cable to prevent electrical shorts.

2. 2

   Locate pedal assembly

   Locate the electronic foot pedal assembly on the cab floorboard.

3. 3

   Disconnect harness

   Carefully depress the locking tab and disconnect the electrical wiring harness connector from the pedal sensor.

4. 4

   Remove mounting hardware

   Remove the mounting bolts/hardware securing the pedal assembly to the floor or mounting bracket.

5. 5

   Remove faulty pedal

   Remove the faulty pedal assembly from the cab.

6. 6

   Install new pedal

   Position the new accelerator pedal assembly and secure it with the mounting hardware.

7. 7

   Reconnect harness

   Reconnect the electrical harness connector, ensuring it clicks securely into place.

8. 8

   Reconnect battery

   Reconnect the battery ground cable.

9. 9

   Clear code and test

   Turn the ignition on and use a diagnostic scan tool to clear fault code 3366. Test the pedal operation to ensure the Engine ECU recognizes the full range of motion (some models may require a brief pedal calibration/relearn procedure via the dash or scan tool).