Electronic fault codes active or high counts of inactive fault codes
View and troubleshoot the fault codes with INSITETM. Refer to the Troubleshooting and Repair
Manual, CM2100 and CM2150 Electronic Control System, Bulletin 4021570.
Cold weather radiator cover or winterfront is closed
Open the cold weather radiator cover or the winterfront. Refer to the OEM instructions
Radiator shutters are not opening completely, or the shutterstat setting is wrong
Inspect the radiator shutters. Repair or replace if necessary. Check the shutterstat setting. Refer to
the OEM service manual.
Charge air cooler fins, radiator fins, or air conditioner condenser fins are damaged or obstructed with debris
Inspect the charge air cooler, air conditioner condenser, and radiator fins. Clean, if necessary.
Refer to Procedure 010-027 and the OEM service manual.
Coolant level is below specification
Check the coolant level. Check for an external leak. Refer to Procedures 008-018 and the Coolant Leak External Sympton Tree. Sample the lubricating oil and have a laboratory check for coolant in the oil (internal leak).
Coolant mixture of antifreeze and water is not correct
Verify the concentration of antifreeze in the coolant. Add antifreeze or water to correct the concentration. Refer to the Cummins Coolant Requirements and Maintenance, Bulletin 3666132.
Fan shroud is damaged or missing or the air recirculation baffles are damaged or missing
Inspect the shroud and the recirculation baffles. Repair, replace, or install, if necessary. Refer to
Procedure 008-038.
Fan drive belt is broken or loose
Check the fan drive belt. Replace the belt if necessary. Refer to Procedure 008-002.
Fan drive or fan controls are malfunctioning
Check the fan drive and controls. Refer to Procedure 008-026 if electronically controlled by he engines’s ECM. If OEM controlled, refer to the OEM service manual.
Coolant temperature gauge or sensor is malfunctioning
Test the gauge and the sensor. Repair or replace, if necessary. Refer to the OEM service manual instructions on troubleshooting the gauge. Refer to the Troubleshooting and Repair Manual, CM2100 and CM2150 Electronic Control System, Bulletin 4021570, to monitor and check the coolant temperature sensor.
Radiator cap is not correct, is malfunctioning, or has low-pressure rating
Check the radiator pressure cap. 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.
Cooling system hose is collapsed, restricted, or leaking
Inspect the hoses. Refer to Procedure 008-020.
Fill line or vent lines are restricted, obstructed, or not routed correctly
Check the vent lines and the fill line for correct routing and for restriction. Refer to the OEM
service manual.
Intake manifold air temperature is above specification
Refer to the Intake Manifold Air Temperature Above Specification symptom tree .
Lubricating oil level is above or below specification
Check the oil level. Add or drain oil, if necessary. Refer to Procedure 007-043.
Cooling system is contaminated with dirt, scale, or sludge
Clean the cooling system. Refer to Procedure 008-018.
Lubricating oil is contaminated with coolant or fuel
Refer to the Lubricating Oil Contaminated symptom tree.
Coolant is contaminated with lubricating oil
Refer to the Lubricating or Transmission Oil in Coolant symptom tree.
Water pump is malfunctioning
Check the water pump for correct operation. Replace the water pump if necessary. Refer to
Procedure 008-062.
Radiator fins are damaged or obstructed with debris
Inspect the radiator fins. Clean and repair the fins as necessary. Refer to Procedure 008-020.
Torque converter is malfunctioning
Check the torque converter. Refer to the OEM service manual.
Torque converter cooler or hydraulic oil cooler is malfunctioning
Remove and inspect the cooler cores and a-rings. Refer to the OEM service manual.
Vehicle cooling system is not adequate
Verify that the engine and vehicle cooling systems are using the correct components. Refer to the
OEM service manual.
Air or combustion gases are entering the cooling system
Check for air or combustion gases in the cooling system. Refer to Procedure 008-020.