Case IH 3002 – Engine Control Unit (ECU A-9000): Signal Range Check High for Acceleration Pedal Position Device Driver Sensor 1

The signal voltage sent from the accelerator pedal position sensor (B-9100) to the control unit is exceeding the maximum allowable threshold of 5.20 V, indicating a short circuit to a high voltage source, an open ground circuit on the sensor wiring, or an internal failure of the sensor itself.

• Farmall
• Steiger T4B
• 240 Series Axial-Flow Combines
• Magnum Series (235, 260, 290, 315, 340, 370)
• MXM Series (MXM120, MXM130, MXM140, MXM155, MXM175, MXM190)
• MXU Series (MXU100, MXU110, MXU115, MXU125, MXU135)
• Maxxum Series
• Puma Series

1. 1

   Visually inspect the wiring harnesses and connectors between the foot throttle sensor (B-9100) and the Engine ECU (A-9000)

2. 2

   Check for damaged, bent, or displaced pins, corroded terminals, or broken wires at the sensor pigtail and the ECU X-9001 connector. Ensure connectors are completely seated.

3. 3

   Perform a harness flex test while monitoring a diagnostic tool or multimeter to reveal any intermittent breaks or shorts in the wiring

4. 4

   Use a multimeter to verify the sensor's 5V reference circuit and check the ground circuit for continuity to the chassis/ECU ground (an open ground will cause the signal voltage to spike above 5.20V)

5. 5

   Verify that the ECU A-9000 software is up to date and functioning correctly if no physical wiring fault is found

1. 1

   Power Down

   Turn off the machine, remove the key, and ensure the equipment is safe to work on.

2. 2

   Locate the Sensor

   Locate the accelerator pedal position sensor (B-9100) mounted on the foot throttle pedal assembly inside the cab.

3. 3

   Disconnect

   Unplug the electrical harness connector from the sensor.

4. 4

   Test the Circuit

   Turn the key to the ON position (engine off). Probe the harness connector to ensure the 5V reference is present and the ground is intact. If the signal wire is showing >5.20V with the sensor unplugged, you have a short-to-power in the wiring harness that must be repaired.

5. 5

   Replace Sensor

   If the wiring tests perfectly, the sensor has failed internally. Unbolt the faulty sensor from the pedal assembly.

6. 6

   Install New Part

   Mount the new OEM throttle position sensor and reconnect the wiring harness.

7. 7

   Clear Codes & Calibrate

   Connect a Case IH diagnostic tool (or equivalent like Jaltest) to the diagnostic port. Clear the 3002 / 16B1 fault code. Some drive-by-wire systems may require a brief pedal calibration routine via the software.

8. 8

   Test Operation

   Start the engine and test the foot throttle through its full range of motion to ensure the signal stays within the normal range and the code does not return.