Case IH 144 – Engine Control Unit (ECU) / Transmission Control Unit / Implement Controller: Coolant Temperature Sensor Circuit / System Pressure Transducer Short

Code 144 (Coolant Temperature Sensor Circuit): High voltage is detected at coolant temperature signal pin 2 of the sensor harness connector, which disables engine protection for coolant temperature and may cause white smoke. Code 2160 (System Pressure Transducer Short): The control module has detected that the voltage signal from the system pressure transducer is abnormally high, indicating a short to the 5-volt reference wire or Battery Positive (B+), or an internal sensor failure.

• STX Steiger
• Case IH STX Steiger Tractors
• Case IH Magnum Tractors (MX210, MX230, MX255, MX285)
• Case IH Early Riser Planters (2150, 2160)

1. 1

   Verify if the fault code is currently active or stored in history to determine if the issue is intermittent.

2. 2

   Locate the sensor (coolant temperature or system pressure) and the ECU/Controller. Ensure connectors are fully seated, undamaged, and pins have a tight fit.

3. 3

   Disconnect the sensor and the ECU, then test the signal wire for continuity.

4. 4

   Leave connectors disconnected and test the signal circuit with a multimeter to check for a short to the 5V reference pin or a 12V battery source.

1. 1

   Power Down

   Turn off the machine and disconnect battery power to prevent electrical spikes.

2. 2

   Inspect Connectors

   Disconnect the harness from the system pressure transducer. Inspect the pins for corrosion, moisture, or pushed-back terminals. Repair or replace the connector pigtail if damaged.

3. 3

   Isolate the Short

   If the connector is in good condition, trace the wiring harness back to the ECU. Look for rub-through spots where the wire insulation may have chafed against the chassis or other wires, causing the short to B+ or the 5V reference.

4. 4

   Replace the Sensor

   If the wiring harness tests perfectly fine (no shorts found in the harness), the short is likely internal to the system pressure transducer. Replace the sensor.

5. 5

   Clear and Test

   Reconnect all components. Power on the machine and return it to proper operation. Note that for some emissions/engine-related codes, the machine must be brought to operating temperature and run under load for up to 30 minutes until the fault clears.