C11, C13, C15, and C18 Industrial Engines Caterpillar

Use this procedure to troubleshoot high coolant temperature or if one of the codes in Table 1 is active.

Table 1

Diagnostic Trouble Codes
CDL Code and Description	Comments
E361(3) Engine Coolant Temperature High - Most Severe (3)	The engine coolant temperature has exceeded the trip point and the delay time has expired. Engine power is derated. The code is logged.
E361(1) Engine Coolant Temperature High- Least Severe (1)	The engine coolant temperature has exceeded the trip point and delay time has expired. The code is logged.
E361(2) High Engine Coolant Temperature High - Moderate Severity (2)	The engine coolant temperature has exceeded the trip point and the delay time has expired. The code is logged.

Probable Causes

• Low Coolant Level and/or Coolant Leakage

• Coolant Temperature Sensor

• Water Temperature Regulator and/or Pressure Relief Valve

• Radiator

• Heat Exchanger

• Engine Cooling Fan (if equipped)

• Coolant Pump

• Cylinder Head Gasket

Recommended Actions

Table 2

Troubleshooting Test Steps	Values	Results
1. Inspect the Engine Coolant Level	Engine Coolant Level	Result: The engine coolant level is OK. Proceed to Test Step 2. Result: The engine coolant level is NOT OK. Repair: Check the cooling system for leaks. Refer to Troubleshooting, "Coolant Level is Low" for additional information. Repair any leaks immediately. If the problem is not resolved, proceed to Test Step 2.
2. Check the Coolant Temperature Sensor and/or the Circuit A. Check the reading of the coolant temperature on Cat ET. The temperature should rise steadily as the engine is warmed. Ensure that the temperature is within operating specifications.	Coolant Temperature Sensor	Result: The temperature sensor is OK. Proceed to Test Step 3. Result: The temperature sensor is NOT OK. Repair: Troubleshoot the circuit and the coolant temperature sensor. Refer to Troubleshooting, "Sensor Signal (Analog, Passive) - Test". If the problem is not resolved, proceed to Test Step 3.
3. Check the Water Temperature Regulator and/or Pressure Relief Valve A. Pressure-test the cooling system. Refer to Systems Operation/Testing and Adjusting for the correct procedure. B. Check that the seating surfaces of the pressure relief valve and the radiator cap are clean and undamaged. C. Check operation of the pressure relief valve and/or the water temperature regulator.	Temperature Regulator	Result: The pressure relief valve and/or the water temperature regulator are OK. Proceed to Test Step 4. Result: The pressure relief valve and/or the water temperature regulator are NOT OK. Repair: Clean the components and/or replace the components. If the problem is not resolved, proceed to Test Step 4.
4. Inspect the Radiator A. Check the radiator fins for dirt, debris, and/or damage. B. Check for collapsed hoses and/or other restrictions. C. Check the radiator for internal blockage. Note: Ensure that the radiator size is sufficient. An undersized radiator does not have enough area for the effective release of heat. An undersized radiator may cause the engine to run at a temperature that is higher than normal. The normal temperature depends on the ambient temperature.	Radiator	Result : The radiator is OK. Proceed to Test Step 5. Result : The radiator fins are damaged. Repair: Remove any dirt and/or debris and straighten any bent fins. Result The radiator has internal blockage. Repair: Remove the blockage. If the problem is not resolved, proceed to Test Step 5.
5. Check the Heat Exchanger for Sufficient Flow A. Check for sufficient flow and temperature of the cooling water through the heat exchanger.	Heat Exchanger	Result : The heat exchanger is OK. Proceed to Test Step 6. Result : The heat exchanger is NOT OK. Repair: Determine the location of the obstruction. If the temperature of the cooling water is too high, determine the cause. Ensure that the size of the heat exchanger is sufficient. Make the necessary repairs. If the problem is not resolved, proceed to Test Step 6.
6. Faulty Engine Cooling Fan (if equipped) A. If the fan is belt driven, check for loose drive belts. Note: A loose fan drive belt will cause a reduction in the air flow across the radiator. B. Check the fan clutch, if equipped. Note: A fan clutch or a hydraulic driven fan that is not turning at the correct speed can cause improper air speed across the radiator core. The lack of proper air flow across the radiator core can cause the coolant not to cool to the proper temperature differential.	Engine cooling fan	Result : The fan clutch is OK. Proceed to Test Step 7. Result : The fan belt is OK. Proceed to Test Step 7. Result : The fan belt is NOT OK. Repair: Adjust the tension of the fan drive belt, if necessary. Refer to Operation and Maintenance Manual. Result The fan clutch is NOT OK. Repair: Refer to Troubleshooting, "Cooling Fan Control - Test" for troubleshooting information. If the problem is not resolved, proceed to Test Step 7.
7. Inspection of the Coolant Pump A. Inspect the impeller of the coolant pump for damage and/or erosion. B. Make sure that the drive gear is not loose on the drive shaft of the coolant pump.	Coolant Pump	Result : The coolant pump is OK. Proceed to Test Step 8. Result : The coolant pump is NOT OK. Repair: If necessary, replace the coolant pump. Refer to Disassembly and Assembly for the correct procedure. If the problem is not resolved, proceed to Test Step 8.
8. Inspect the Cylinder Head Gasket A. Remove the cylinder head. Refer to the Disassembly and Assembly manual. B. Check the cylinder liner projection. Refer to the Systems Operation/Testing and Adjusting manual. C. Pressure test the head for leaks. D. Install a new cylinder head gasket and new water seals in the spacer plate. Refer to the Disassembly and Assembly manual.	Head Gasket	Result : The cylinder head was checked for leaks and the gasket was replaced.

If the problem is not resolved, contact your Technical Communicator (TC). For further assistance, the TC can confer with the Dealer Solutions Network (DSN).