Case IH 19 – ARM (Armrest Controller): Hand THROTTLE potentiometer is failed

The electronic sensor (potentiometer) responsible for converting the physical position of the hand throttle lever into an electrical signal has failed, is sending an implausible signal, or has an open/short circuit. When this fails, the machine may experience erratic throttle response, surging RPMs, or a check engine light.

• MX Magnum
• STX Steiger
• TG Series
• Puma
• Steiger
• Quadtrac
• CS/CVX
• T6
• T7
• TM Series
• TS Series

1. 1

   Inspect the wiring harness for a broken wire located just an inch or two below the sensor plug inside the armrest

2. 2

   Verify that the sensor is receiving the correct reference voltage from the ARM controller (often a 5V or 8V reference depending on the exact model/year)

3. 3

   Check for related secondary codes that might indicate a broader voltage issue, such as ARM 10091 (Armrest Controller 5V regulator failure) or ARM 9041 (Hand throttle potentiometer calibration results not acceptable)

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical shorts.

2. 2

   Access the Sensor

   Disassemble the side console/armrest housing to expose the internal linkage of the hand throttle lever.

3. 3

   Remove the Old Sensor

   Unplug the wiring harness connector from the throttle potentiometer. Remove the retaining screws/lock nuts holding the sensor to the throttle lever assembly.

4. 4

   Install the New Sensor

   Slide the new potentiometer onto the throttle shaft, ensuring the internal alignment tabs match the physical position of the lever. Secure the mounting hardware and reconnect the wiring harness.

5. 5

   Reassemble

   Put the armrest console back together.

6. 6

   Mandatory Calibration

   You must calibrate the new potentiometer. Because the new sensor will have slightly different minimum and maximum voltage limits, the ARM controller needs to learn the new sweep. This is done via the tractor's instrument cluster diagnostic menu or by using a diagnostic laptop tool (like CNH EST or Jaltest).