M11 Series – Service Manual – Coolant Temperature Below Normal

Electronic fault codes active or high counts of inactive fault codes

Refer to Section TF in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin 3666130, or Section TF in the Troubleshooting and Repair Manaul for CELECT™ Systems, Bulletin 3666084.

Engine is operating at low ambient temperature

Check the winterfront, shutters, and under-the-hood air. Use under-the-hood intake air in cold weather. Refer to Operation of Diesel Engines in Cold Climates, Bulletin 3379009.

Coolant fill line is not routed correctly

Check the routing of the coolant fill line. Refer to the OEM service manual.

Coolant temperature gauge is malfunctioning

Test the temperature gauge. Repair or replace the gauge, if necessary. Refer to Procedure 008-004 and the OEM service manual.

Coolant temperature sensor is malfunctioning

Check the coolant temperature sensor. Refer to Procedure 019-019 in the Troubleshooting and Repair Manual for CELECT™ Plus Systems, Bulletin No. 3666130, or Section TF in the Troubleshooting and Repair Manaul for CELECT™ Systems, Bulletin No. 3666084.

Radiator shutters are stuck open or opening early

Check the shutter operation. Repair or replace the shutters if necessary. Refer to Procedure 008-049 and the OEM service manual.

Fan drive or fan controls are malfunctioning

Check the fan drive and controls. Refer to 008-024, 008-025, 008-026, 008-027, or 008-028.

Cooling system component is malfunctioning

Perform the cooling system diagnostics test. Refer to Procedure 008-020.

Thermostat is not correct or is malfunctioning

Check the thermostat for the correct part number and for correct operation. Refer to Procedure 008-013.

Thermostat seal is damaged, missing, or not installed correctly.

Check the thermostat seal for damage and correct installation. Refer to Procedure 008-016.

Coolant flow through the radiator is not correct

Check for correct coolant flow through the radiator. Refer to Procedure 008-042.