Case IH 1024 – INST: Trans oil filter switch shorted to ground on power up

The electrical circuit for the transmission oil filter restriction/pressure switch is registering a short to ground immediately when the machine's electrical system is powered on, preventing the system from accurately reading the filter's status.

• MX Magnum
• Case IH Magnum 235
• Case IH Magnum 250
• Case IH Magnum 280
• Case IH Magnum 310
• Case IH Magnum 340
• Case IH Magnum 380
• Case IH Magnum Rowtrac
• Case IH Steiger 350
• Case IH Steiger 400
• Case IH Steiger 450
• Case IH Steiger 500
• Case IH Steiger 550
• Case IH Steiger 600
• Case IH Steiger Quadtrac

1. 1

   Visually inspect the wiring harness running from the transmission oil filter switch to the Instrument Controller for chafed insulation, pinched wires, or melted casing.

2. 2

   Disconnect the plug at the transmission oil filter switch and inspect the pins for corrosion, moisture ingress, or debris that could be bridging the connection to ground.

3. 3

   Perform a circuit isolation test: with the switch disconnected, use a multimeter to check the signal wire for continuity to ground. If continuity exists, the short is in the wiring harness. If it disappears, the switch is internally shorted.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the negative battery cable to prevent electrical surges.

2. 2

   Locate the Switch

   Locate the transmission hydraulic oil filter housing (usually mounted on or near the transmission block). The restriction/pressure switch is threaded directly into the filter head.

3. 3

   Clean the Area

   Thoroughly clean the area around the filter head and switch to prevent dirt from entering the hydraulic system when the switch is removed.

4. 4

   Remove the Switch

   Unplug the electrical connector. Use a wrench to carefully unscrew the faulty switch from the filter head housing. Have a rag ready, as a small amount of transmission fluid may weep from the port.

5. 5

   Install the New Switch

   Thread the new OEM switch into the filter head. Tighten it to the manufacturer's specified torque (do not overtighten, as the filter head threads can be damaged).

6. 6

   Reconnect

   Plug the electrical connector back into the switch, ensuring the locking tab clicks into place.

7. 7

   Test

   Reconnect the battery, power up the tractor, and verify on the instrument cluster that fault code 1024 is no longer active. Check the switch area for any fluid leaks while the tractor is running.