New Holland 3003 – ECU: Accelerator Pedal Signal - SOURCE LOW

The Engine Control Unit (ECU) has detected that the voltage or pulse-width modulated (PWM) signal from the accelerator pedal position sensor is lower than the bottom limit of its expected operational range. This indicates that the accelerator pedal is in a lower position than expected, or there is an electrical fault such as a short circuit to ground in the signal wire, a faulty sensor, or a wiring harness issue. This condition may affect the proper operation of the machine's speed control system, resulting in a lack of engine power, erratic idle, or engine stalling.

• TM115
• TM120
• TM125
• TM130
• TM135
• TM140
• TM150
• TM155
• TM165
• TM175
• TM190
• T4020
• T4030
• T4040
• T4050
• T6010
• T6020
• T6030
• T6040
• T6050
• T6060
• T6070
• T7030
• T7040
• T7050
• T7060
• Workmaster 50

1. 1

   Visually inspect the wiring harness and connectors between the accelerator pedal sensor and the ECU for chafed wires, pinched wires, corrosion, or loose pins

2. 2

   Verify the sensor is receiving the correct voltage supply (approximately +5 volts) and has a solid ground connection

3. 3

   Test the signal wire voltage while depressing the pedal; the voltage should increase gradually and smoothly without dropping low

4. 4

   With the sensor disconnected, measure resistance between the signal and ground pins (reference values: ~900-1000 Ω depressed, 3.7 kΩ released, though values may vary by specific sensor type)

1. 1

   Ensure Safety

   Before beginning any work, turn off the tractor and disconnect the battery to prevent electrical damage.

2. 2

   Locate the Sensor

   The accelerator pedal sensor, also known as a foot throttle potentiometer, is located at the foot throttle pedal assembly.

3. 3

   Perform Diagnostic Tests

   Conduct the visual inspection and electrical tests outlined above to confirm if the fault lies with the sensor itself, the wiring, or the connectors.

4. 4

   Address Wiring Issues

   If any damaged wiring or corroded connectors are found, repair or replace them as necessary. Ensure all connections are clean and secure.

5. 5

   Replace the Sensor

   If the diagnostic tests confirm the sensor is faulty, it must be replaced. Unbolt the old sensor from the pedal assembly, disconnect its electrical connector, and install the new sensor in its place.

6. 6

   Reconnect and Re-test

   Once the new sensor is installed, reconnect the battery and turn the key to the 'on' position without starting the engine. Clear the fault code using the tractor's diagnostic menu or a service tool.

7. 7

   Verify Operation

   Start the engine and check for the return of the fault code. Test the throttle response to ensure it is operating smoothly and correctly. In some cases, a calibration procedure may be required after replacing the sensor.