Case IH 3367 – Engine Control Module (ECM): Coolant Temperature Test Failure

Triggered when the engine's monitoring system detects that the engine coolant has failed to reach a minimum temperature threshold within a specified timeframe, or the sensor's reading is implausible compared to other engine parameters (such as ambient air or oil temperature).

• Case IH Magnum 235 - 340 (Series 4)
• Case STX Steiger series (350 to 600 horsepower)
• Case IH Farmall series
• Case 721F Wheel Loader
• Case 821F Wheel Loader
• Case 921F Wheel Loader

1. 1

   Verify if the machine is operating in extreme cold ambient conditions, which can naturally delay engine warm-up and trigger a false failure.

2. 2

   Inspect the coolant temperature sensor, its electrical connector, and the wiring harness for damage, corrosion, or short circuits.

3. 3

   Use the CNH EASy (Electronic Service Tool) to monitor live coolant temperature data. Look for erratic readings, drop-outs, or a temperature that stays completely static.

4. 4

   If the sensor reading is accurate but the engine is genuinely failing to reach operating temperature, check the engine thermostat as it is likely stuck open.

1. 1

   Clear and Retest

   Connect the approved diagnostic equipment (EASy tool), clear the 3367 error code, and run the machine under normal operating conditions to see if the code returns.

2. 2

   Repair Wiring

   If the diagnostic checks revealed a short or open circuit in the harness, repair the damaged wiring or replace the connector pigtail.

3. 3

   Replace the Sensor

   If the wiring is intact but the sensor is faulty: Allow the engine to cool completely. Drain a small amount of coolant from the radiator to bring the fluid level below the sensor port. Disconnect the electrical harness from the coolant temperature sensor. Unthread the old sensor and install the new OEM replacement. Reconnect the harness.

4. 4

   Replace the Thermostat

   If the sensor is working but the engine runs cold, remove the thermostat housing, extract the stuck thermostat, and install a new one with a fresh gasket.

5. 5

   Refill and Bleed

   Top off the engine coolant and bleed any air from the cooling system.

6. 6

   Final Verification

   Start the engine, allow it to reach normal operating temperature, and verify via the diagnostic tool that the fault code does not return.