New Holland TRANS 37 – Transmission Controller (TRANS): BOC switch open circuit or Neutral relay stuck open.

Recorded when the inching (clutch) pedal position is above 30%, the shuttle lever is in Forward or Reverse, and the controller does not detect +12V from the bottom of clutch relay.

• New Holland TG Series (TG210, TG230, TG255, TG285)
• New Holland T8 Series (T8010, T8020, T8030, T8040, T8050)
• New Holland T9 and T9000 Series
• New Holland MXM / TM Series

1. 1

   Inspect the inching (clutch) pedal, its position potentiometer, and the BOC switch assembly to ensure proper, tight, and correctly adjusted mechanical installation

2. 2

   Test the Bottom of Clutch (BOC) switch for an open circuit (a healthy switch should have very low resistance, around 4 ohms, when closed; 8,000+ ohms indicates failure)

3. 3

   Check the Neutral relay to see if it has failed or is stuck open

4. 4

   Verify power supply to the Neutral relay and inspect all wiring and connections leading to both the Neutral relay and the BOC switch for damage or loose connections

1. 1

   Adjust the Pedal Assembly

   If the diagnostic checks reveal a loose or misadjusted clutch pedal stop, clutch pedal position potentiometer, or BOC switch, tighten and slightly adjust the mechanical installation so the switch engages correctly.

2. 2

   Replace the BOC Switch

   If the BOC switch tests bad (failed open or high resistance), disconnect the electrical connector, remove the faulty switch from the clutch pedal assembly, install the new switch, and recalibrate/test.

3. 3

   Replace the Neutral Relay

   If the BOC switch is functioning properly but the controller still does not detect +12V, locate the Neutral relay in the tractor's electrical power distribution system (fuse/relay box) and replace it.

4. 4

   Repair Wiring

   If both components test fine, trace the wiring harness between the BOC switch, Neutral relay, and Transmission controller to repair any broken wires or corroded connectors.