Massey Ferguson 04.X.99 – Transmission Control Unit (TRANS2): Issue With Powershift P Solenoid Supply Voltage

The transmission control unit has detected an irregularity (such as an open circuit, short circuit, or out-of-range voltage) in the electrical supply going to the "P" solenoid, which is responsible for controlling specific powershift/range changes within the transmission.

• 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
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613

1. 1

   Inspect the wiring harness running from the TRANS2 module to the transmission solenoid bank for chafed wires, rodent damage, or pinched lines

2. 2

   Disconnect the plug at the Powershift P Solenoid and inspect for water ingress, corrosion, or bent pins. Clean with contact cleaner if necessary

3. 3

   Turn the key to the ON position and use a multimeter to verify that the correct reference voltage is reaching the solenoid connector

4. 4

   Measure the internal resistance (Ohms) of the P Solenoid. An open circuit (infinite resistance) or a dead short indicates the solenoid coil has failed internally

5. 5

   Check transmission control fuses and relays in the main fuse box to ensure they are intact and seated properly

1. 1

   Preparation

   Park the tractor on a level surface, engage the parking brake, and turn off the engine. Disconnect the negative battery terminal.

2. 2

   Locate the Solenoid Bank

   Locate the powershift/range change solenoid bank on the side of the transmission housing.

3. 3

   Clean the Area

   Thoroughly clean the area around the solenoids with brake cleaner or a degreaser to prevent dirt from entering the transmission valve body when the solenoid is removed.

4. 4

   Remove the Solenoid

   Disconnect the electrical connector from the faulty P Solenoid. Remove the retaining bolts or snap ring holding the solenoid in place.

5. 5

   Extract and Replace

   Pull the solenoid straight out. Lubricate the O-rings on the new solenoid with clean transmission fluid. Carefully insert the new solenoid into the valve body, ensuring it seats fully without pinching the O-rings.

6. 6

   Reassembly

   Reinstall the retaining hardware and reconnect the electrical plug.

7. 7

   Clear Codes and Test

   Reconnect the battery, turn the key on, and use a diagnostic tool (or the tractor's onboard dash menu) to clear the 04.X.99 fault code. Start the tractor and test the powershift functions through all ranges to ensure smooth engagement.