New Holland 3003 – ECM: Accelerator Pedal Angle-of-Rotation Potentiometer Voltage Too Low

The Engine Control Module (ECM) has detected that the voltage signal from the accelerator pedal's angle-of-rotation potentiometer is below the minimum expected range. This indicates a potential short circuit or internal sensor fault, which can cause the foot throttle to become unresponsive and impede proper control of the tractor's engine speed.

• T6020
• T6030
• T6050
• T6070
• T6080
• T6090
• T7 Series
• T7 CVX Series
• T8.xxx Series
• TS100A
• TS110A
• TS115A
• TS125A
• TS135A
• T5.95
• T5.105
• T5.115
• T5.120
• TL Series
• TM Series
• TC Combine Harvesters
• CX Combine Harvesters
• E Series Wheel Loaders
• F Series Wheel Loaders

1. 1

   Check for 5-Volt Supply: Test for a 5-volt supply at terminal 4 of the accelerator pedal connector (e.g., connector 160, wire 942A). If 5 volts are not present, check the circuit back to the corresponding pin at the control unit connector (e.g., pin 8 of connector 350M (CN1-A) at the TCU). If there is no 5-volt supply from the control unit, the unit itself may be faulty.

2. 2

   Verify Ground Circuit: Check the ground connection. With the voltmeter's positive lead on a known good 12v source, touch the negative lead to the ground pins at the pedal connector (e.g., pins 7 and 8). A reading of 12v indicates a good ground. If there is no voltage, trace the ground circuit back to the control unit.

3. 3

   Test Potentiometer Signal Voltage: Connect a voltmeter between the signal output pin of the potentiometer (e.g., terminal 2, wire 944A) and the ground pin (e.g., pin 8, wire 557L). As the accelerator pedal is slowly pressed, the voltage should increase smoothly. A typical range is from approximately 0.55V at idle to 4.15V at full throttle. If the voltage does not change smoothly, or if it drops to zero or spikes unexpectedly, the potentiometer is likely faulty.

4. 4

   Inspect Wiring and Connectors: Visually inspect the wiring harness between the accelerator pedal and the control module for any signs of damage, such as chafing, corrosion, or loose connections.

1. 1

   Perform Diagnostics

   Complete the diagnostic checks listed above to confirm that the potentiometer is the source of the fault.

2. 2

   Replace the Potentiometer

   If the diagnostic tests indicate a faulty potentiometer, it will need to be replaced. The potentiometer is typically part of the foot throttle assembly.

3. 3

   Calibration

   After replacing the foot throttle assembly or potentiometer, a calibration may be necessary. Some systems may auto-calibrate. One possible method involves turning the key on, unplugging the new potentiometer for about five seconds, and then plugging it back in. The dash may beep or flash a light to indicate it's in calibration mode. Slowly press the pedal and hold it until the beeping stops, then turn the key off to store the calibration. Note that specific calibration procedures can vary by model, and consulting the official service manual is recommended.