Massey Ferguson 13.00.48 – HITCH: Park Brake Switch Not Opening When Park Brake Engaged Dyna 6 (HITCH)

The tractor's electronic control system expects the park brake switch circuit to break continuity (open) when the parking brake is applied. Because the circuit is not opening, the system detects a fault. This underlying condition is typically caused by a mechanically stuck switch, a switch that has failed internally (stuck closed), a misadjusted switch bracket, or a short-to-ground in the wiring harness.

• 7724S
• 5712SL
• 7722
• 7722S
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• Dyna-6 transmission
• 6400 series
• 6700 S series
• 7600 series
• 7614
• 7615
• 7616
• 7618
• 7624
• 7700 series

1. 1

   Inspect the park brake lever mechanism and the physical switch for dirt, debris, or mechanical binding that might prevent the switch plunger from fully actuating when the brake is engaged.

2. 2

   Disconnect the switch and use a digital multimeter to test for continuity. The switch is a "Normally Closed" type. It should show continuity when the brake is disengaged and should "Open" (no continuity) when the brake is engaged. If it remains closed regardless of the lever's position, the switch is faulty.

3. 3

   Inspect the wiring harness between the park brake switch and the HITCH module. Look for chafed wires that might be shorting to the tractor's chassis (ground), which would mimic a closed switch to the controller.

4. 4

   Verify that the mechanical linkage or handbrake lever is making proper physical contact with the switch actuator.

1. 1

   Park the tractor on a level surface, turn off the engine, and remove the key. Chock the wheels to prevent the tractor from rolling, as you will be working on the parking brake system.

   Park the tractor on a level surface, turn off the engine, and remove the key. Chock the wheels to prevent the tractor from rolling, as you will be working on the parking brake system.

2. 2

   Locate the park brake switch. Depending on the specific model's cab layout, this will be located either at the base of the handbrake lever inside the cab console or mounted near the transmission ParkLock mechanism.

   Locate the park brake switch. Depending on the specific model's cab layout, this will be located either at the base of the handbrake lever inside the cab console or mounted near the transmission ParkLock mechanism.

3. 3

   Disconnect the electrical wiring harness connector from the switch.

   Disconnect the electrical wiring harness connector from the switch.

4. 4

   Loosen the retaining nuts or mounting screws securing the switch to its bracket and remove the faulty switch.

   Loosen the retaining nuts or mounting screws securing the switch to its bracket and remove the faulty switch.

5. 5

   Install the new park brake switch. If the switch body is threaded, carefully adjust the mounting depth so that the brake lever properly depresses the switch plunger to open the circuit when engaged, without crushing the switch body.

   Install the new park brake switch. If the switch body is threaded, carefully adjust the mounting depth so that the brake lever properly depresses the switch plunger to open the circuit when engaged, without crushing the switch body.

6. 6

   Tighten the retaining nuts/screws and reconnect the electrical harness.

   Tighten the retaining nuts/screws and reconnect the electrical harness.

7. 7

   Turn on the tractor and use the dashboard interface or a diagnostic scan tool to clear the fault codes. Engage and disengage the park brake to verify the code does not return and that the dash indicator functions correctly.

   Turn on the tractor and use the dashboard interface or a diagnostic scan tool to clear the fault codes. Engage and disengage the park brake to verify the code does not return and that the dash indicator functions correctly.