New Holland TMF 126 – TMF: Aux 1st Raise solenoid failed open or short circuit.

The controller's Aux #1 driver is turned on, but no electrical current is being sensed. The system has detected that the extend/raise coil circuit for the first auxiliary remote valve is either broken (open circuit) or shorted directly to ground.

• T8 Series (T8.360, T8.390, etc.)
• T8000 Series (T8010, T8020, T8030, T8040, T8050)
• T9 Series
• TG Series (TG210, TG285, TG305)

1. 1

   Inspect the wiring harness and connector at the Aux 1 remote valve (located at the rear hydraulic stack) for visible damage, chafing, corrosion, or loose pins.

2. 2

   Disconnect the Aux 1 Raise solenoid and measure the resistance across the coil pins using a multimeter. Compare the reading to a known good solenoid (such as the Aux 2 solenoid). An infinite reading indicates an internally open coil; a zero or near-zero reading indicates an internal short.

3. 3

   Check the wiring harness from the solenoid connector back to the TMF controller for continuity and ensure there is no short to ground in the wiring itself.

4. 4

   Swap the Aux 1 Raise solenoid with the Aux 2 Raise solenoid. Clear the codes and operate the remotes. If the fault code changes to TMF 130 (Aux 2nd Raise solenoid failed open/short), the solenoid is definitively the culprit. If TMF 126 persists, the issue lies within the wiring harness or the TMF controller.

1. 1

   Turn off the tractor, engage the parking brake, and disconnect the battery to prevent electrical spikes.

2. 2

   Relieve any residual hydraulic pressure in the auxiliary circuits by moving the remote levers/paddles back and forth.

3. 3

   Locate the Aux 1 remote valve section at the rear hydraulic valve stack.

4. 4

   Disconnect the electrical harness connector from the faulty Aux 1 Raise solenoid.

5. 5

   Remove the retaining nut or bolt holding the solenoid coil to the valve cartridge stem.

6. 6

   Slide the old solenoid coil off the valve stem.

   (Note: You usually do not need to open the hydraulic system or remove the cartridge to replace just the coil).

7. 7

   Slide the new OEM replacement solenoid onto the valve stem and secure it with the retaining nut/bolt.

   Do not overtighten.

8. 8

   Reconnect the electrical harness, ensuring the weather-pack connector is fully seated and locked.

9. 9

   Reconnect the battery, start the tractor, clear the inactive fault codes, and test the Aux 1 remote function to verify the repair.