Case IH 2315 – Transmission Control Module (TCM): Reverse pressure switch - open circuit or short to ground

This code indicates an electrical fault in the circuit for the reverse pressure switch. The system has detected that the signal from the switch is either completely lost (open circuit, such as a disconnected or broken wire) or is shorting directly to the chassis ground (such as a chafed wire).

• Puma/Mid Range Magnum
• Case IH Puma Series
• Case IH Steiger & Quadtrac Series
• Case IH Magnum / MX / TG Series
• Case IH Maxxum Series

1. 1

   Visually inspect the wiring harness leading to the reverse pressure switch on the transmission valve body/shuttle valve block for disconnected plugs, corroded pins, or wires that have rubbed through their insulation and are touching the tractor chassis.

2. 2

   Disconnect the switch and use a multimeter to check the resistance across the switch pins to ensure it shows a closed circuit under specific pressure conditions, and check the harness side for continuity back to the transmission controller.

3. 3

   Verify that the switch is receiving the correct reference voltage from the transmission controller when the key is ON.

4. 4

   Ohm test the forward/reverse solenoids (typically measuring 7-8 ohms) to rule out a cascading electrical issue in the shuttle valve block.

1. 1

   Preparation

   Park the tractor on a level surface, engage the parking brake, and turn off the engine. Crucial: Relieve all hydraulic pressure from the transmission and steering circuits before opening any hydraulic lines or removing sensors.

2. 2

   Locate the Switch

   Locate the reverse pressure switch. On most models, it is located on the transmission regulator valve assembly or the forward/reverse shuttle valve block.

3. 3

   Disconnect

   Unplug the electrical connector from the reverse pressure switch.

4. 4

   Remove the Switch

   Using the appropriate wrench, carefully unthread the faulty pressure switch from the valve block. Have a rag ready to catch any residual hydraulic fluid.

5. 5

   Install the New Switch

   Thread the new OEM pressure switch into the port. Ensure any required O-rings are seated properly (do not over-tighten, as this can damage the valve body threads).

6. 6

   Reconnect

   Plug the electrical harness back into the new switch. Ensure the weather-sealed connection clicks into place securely.

7. 7

   Test

   Start the tractor, allow hydraulic pressure to build, and check for leaks. Clear the fault codes via the tractor's diagnostic menu and test the transmission by shifting into reverse to ensure the code does not return.