Case IH 145 – Transmission/Chassis Control Unit (TCU / Suspension Controller) / Engine Control Unit (ECU) / Main Vehicle Controller: Pressure sensor piston side (DA-K) out of range high / Front Suspension lower lock solenoid circuit shorted or open circuit

OEM documentation indicates a mismatch: TRANS 145 translates to 'Pressure sensor piston side (DA-K) out of range high' or 'Front Suspension lower lock solenoid circuit shorted or open circuit'. The description 'System pressure critically low' is actually logged under Fault Code 2023. Engine Code 145 means 'Coolant Temperature Sensor Circuit - Low voltage detected'.

• STX Steiger
• Magnum 180
• Magnum 200
• Magnum 220
• Magnum 235
• Magnum 275
• Magnum 340
• Puma 130
• Puma 145
• Puma 160
• Steiger

1. 1

   For TRANS 145 (Front Suspension Piston Sensor/Solenoid): Locate the front suspension piston side pressure sensor (DA-K) and the lower lock solenoid. Check the wiring harness for visible damage, rubbing, or pinched wires.

2. 2

   For TRANS 145: Disconnect the sensor/solenoid and use a multimeter to check for continuity. Verify that the circuit is not shorted to ground or shorted to the battery (B+).

3. 3

   For TRANS 145: Monitor the sensor voltage during a calibration attempt; it should remain within the specified range (typically not dropping below 740mV or exceeding 1000mV erratically).

4. 4

   For 'System Pressure Critically Low' condition (Code 2023 / TRANS 146): Verify that the hydraulic/transmission fluid is at the correct level.

5. 5

   For 'System Pressure Critically Low' condition: Inspect the high-pressure, low-pressure, and steering circuits for external leaks.

6. 6

   For 'System Pressure Critically Low' condition: Test the variable displacement pump and charge pump output pressures using a manual pressure gauge to verify if the sensor is reading accurately or if there is a genuine mechanical pressure loss.

1. 1

   Secure the Machine

   Park the tractor on a level surface, engage the parking brake, and safely support the front suspension to relieve pressure from the hydraulic cylinders.

2. 2

   Disconnect Battery

   Disconnect the negative battery terminal to prevent electrical shorts.

3. 3

   Remove the Sensor

   Locate the piston side pressure sensor on the front suspension manifold. Disconnect the electrical harness and carefully unscrew the sensor. Have a catch pan ready for minor hydraulic fluid loss.

4. 4

   Install New Sensor

   Thread the new pressure sensor into the manifold and tighten to OEM torque specifications. Reconnect the electrical harness.

5. 5

   Clear Codes and Calibrate

   Reconnect the battery. Clear the stored fault codes using an Electronic Service Tool (EST).

6. 6

   Suspension Calibration

   Initiate the front suspension calibration process (often requiring the tractor to be running and stationary). Ensure the rod side and piston side pressures read accurately (e.g., ~16,200 kPa for piston side, depending on load) and that the suspension travels through its full range without throwing Code 141 or 150.