Case IH 74 – Transmission Controller (TRANS): The park brake is commanded on and gear is engaged, but there is no park brake request from calibration.

This is a logic error within the transmission system. The controller detects that the transmission is in gear while the park brake is simultaneously engaged, yet the software/calibration is not requesting the park brake to be on. It is most commonly caused by a physical failure of the FNRP (Forward-Neutral-Reverse-Park) shuttle switch pod sending illogical position signals, or a failing park brake solenoid coil that loses power and defaults the tractor into Park while moving.

• MX Magnum
• STX Steiger
• Case IH Magnum Series: MX210, MX230, MX255, MX285, 215, 235, 240, 275, 290, 305, 315, 335, 340
• Case IH Steiger / Quadtrac Series: STX375, STX450, 450, 500, 535

1. 1

   Check for accompanying codes (e.g., TRANS 51, 59, or 60) which indicate the FNRP pod is in an illogical state (FNRP pod cause)

2. 2

   Check for code TRANS 65 indicating 12V supply voltage low (Solenoid or wiring cause)

3. 3

   Using an Electronic Service Tool (EST), verify if the FNRP shuttle lever is selecting and broadcasting each position properly to the controller (FNRP pod cause)

4. 4

   Check transmission circuit fuses to see if a shorted park brake solenoid coil has blown a fuse (Solenoid cause)

5. 5

   Test the electrical connection at the park brake solenoid and inspect for thermal failure where the coil loses magnetization when hot (Solenoid cause)

1. 1

   Remove console trim

   If the FNRP Pod is the culprit: Power down the machine and remove the steering column/console trim surrounding the shuttle lever.

2. 2

   Disconnect FNRP pod

   Disconnect the chassis harness connector from the FNRP pod.

3. 3

   Replace shuttle lever

   Unbolt the shuttle lever assembly and replace it with a new or remanufactured unit.

4. 4

   Reassemble and clear codes

   Reassemble the console and clear the fault codes.

5. 5

   Locate park brake solenoid

   If the Park Brake Solenoid is the culprit: Locate the park brake solenoid. On many Magnum tractors, it is accessed from the outside right-hand side of the cab. Remove the cab air filter at the top of the steps, then remove the cab pressurizer fan behind it.

6. 6

   Disconnect solenoid connector

   The park brake solenoid is located directly behind the fan housing (usually the closest solenoid to you in the valve bank). Disconnect the 2-pin electrical connector.

7. 7

   Remove solenoid coil

   Remove the retaining nut and slide the coil off the valve stem. (Note: Swollen/failed coils can be very difficult to slide off the stem and may require careful prying).

8. 8

   Install new coil

   Install the updated replacement solenoid coil, secure the nut, and reconnect the harness.

9. 9

   Reassemble and clear codes

   Reinstall the pressurizer fan and cab filter, then clear the codes.