Massey Ferguson 13.X.08 – TRANS1: Air Brake Solenoid Issue

Short circuit to earth (ground) on the X339 Pneumatic Trailer Braking Solenoid Valve. The system detects that the electrical current flowing to the progressive air brake solenoid is grounding out before completing its intended circuit.

• 7724S
• 5712SL
• 7722S
• 7722
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 5600 series
• 5700SL series
• 7600 series
• 7700 series
• 8600 series

1. 1

   Locate the X339 Solenoid on the tractor's air brake valve block.

2. 2

   Inspect the wiring harness from the X339 connector back to the TRANS1 module, paying special attention to the cab transmission harness connections at the fuse box (connectors X347 and X348) for chafed insulation, pinched wires, or melted loom.

3. 3

   Test the solenoid coil by disconnecting the X339 electrical connector and measuring resistance across the pins with a multimeter. Near zero resistance indicates an internal short.

4. 4

   Test the harness for shorts by checking for continuity between the power supply wire in the harness and a known good chassis ground with the solenoid disconnected.

1. 1

   Depressurize the System

   Turn off the tractor, disconnect the battery, and safely bleed all air pressure from the pneumatic braking system.

2. 2

   Address Wiring

   If the diagnostic checks revealed a harness short, splice and repair the damaged wire using heat-shrink connectors, then re-wrap it in a protective conduit.

3. 3

   Replace the Solenoid

   If internally shorted, disconnect the electrical connector from the X339 solenoid, remove the retaining nut or bolts securing the solenoid coil to the pneumatic valve stem, slide the old solenoid off the valve block, slide the new solenoid into place and torque the retaining fastener to OEM specifications, then reconnect the electrical connector.

4. 4

   Test and Clear

   Reconnect the battery, start the tractor, and allow the air compressor to build system pressure. Clear the 13.X.08 fault code using a diagnostic tool or the tractor's onboard terminal. Actuate the trailer brakes to ensure proper operation and verify the code does not return.