New Holland TRANS 48 – TRANS: BOC (Bottom of Clutch) switch or Neutral relay short circuit

Recorded when the clutch pedal position is below 5%, the shuttle lever is in Forward OR Reverse, and the controller detects +12V from the bottom of the clutch relay. This indicates that the circuit is receiving power when it shouldn't be.

• TG210
• TG230
• TG255
• TG285
• T8010
• T8020
• T8030
• T8040
• T8050
• TJ450
• TJ480
• T9000 Series
• T9 Series
• MXM/TM Series
• Magnum
• Steiger

1. 1

   Check the Neutral Relay (most common cause): Locate the Neutral relay in the cab fuse/relay panel and swap it with a known good relay of the same type to see if the code clears.

2. 2

   Test the BOC (Bottom of Clutch) Switch: Disconnect the switch at the base of the clutch pedal and test with a multimeter. A healthy switch should show around 4 ohms when closed; extremely high resistance or being stuck closed indicates failure.

3. 3

   Inspect the Wiring: Check the wiring harness between the BOC switch, the neutral relay, and the transmission controller for rubbed or chafed wires causing a short to power (+12V).

1. 1

   Park and Secure

   Park the tractor on a level surface, engage the parking brake, and turn off the key.

2. 2

   Relay Replacement

   Access the main fuse/relay panel (usually located in the cab console or behind the seat). Pull the faulty Neutral relay. Insert the replacement relay and cycle the key to verify the TRANS 48 code moves to an inactive state or clears.

3. 3

   BOC Switch Replacement

   Locate the BOC switch at the bottom of the clutch pedal linkage. Disconnect the electrical connector from the switch. Unbolt or unthread the switch from its mounting bracket. Install the new switch and adjust it so that it properly engages when the clutch pedal is fully depressed (bottomed out). Reconnect the wiring harness.

4. 4

   Clear Codes and Calibrate

   Turn the key on and clear the fault codes. It is highly recommended to perform a clutch pedal potentiometer calibration after replacing the BOC switch to ensure the controller knows the exact pedal travel limits.