Case IH 19407 (DTC 2D73) – Engine Control Module (ECM) / SCR system controller: Low coolant pressure at inlet of main coolant pump

The pressure of the engine coolant entering the suction side of the main coolant pump has dropped below the normal operating threshold. This condition can lead to pump cavitation and inadequate engine cooling.

• MAXXUM T4E
• 240 Series Axial-Flow® Combines

1. 1

   Verify that the engine coolant is at the proper level and inspect the entire cooling circuit for leaks that could cause a pressure drop.

2. 2

   Check the coolant pressure sensor located at the inlet of the main coolant pump. Inspect the sensor's wiring harness and connector for damage, corrosion, or a short-to-ground.

3. 3

   Inspect the main coolant pump for signs of mechanical failure or cavitation.

1. 1

   Emergency Movement

   If the fault has caused a full engine power loss, the system allows for an 'Emergency Re-start.' This provides 30 seconds of operation without power loss to safely move the machine before the engine automatically reduces to low idle speed.

2. 2

   Resolve Fluid Levels

   Top off the engine coolant if it is low and bleed any air from the cooling system.

3. 3

   Test/Replace the Sensor

   Test the coolant pressure sensor's voltage signal. If the signal is below the normal operating range or the sensor is internally shorted, replace the coolant pressure sensor.

4. 4

   Repair Wiring

   If the sensor tests good but the code persists, repair or replace the damaged section of the wiring harness leading back to the ECM.

5. 5

   Replace the Pump

   If the sensor and wiring are functioning correctly but the inlet pressure remains genuinely low, the main coolant pump or the pressure-controlled valve may be failing and will need to be replaced.