PULLER-LEG 1U5839 - Caterpillar

Probable Causes
Extreme ambient temperatures
Cooling system fault
Coolant temperature sensor
Water temperature regulatorRecommended Actions
Note: The procedures have been listed in order of probability. Complete the procedures in order.
Personal injury can result from hot coolant, steam and alkali.At operating temperature, engine coolant is hot and under pressure. The radiator and all lines to heaters or the engine contain hot coolant or steam. Any contact can cause severe burns.Remove filler cap slowly to relieve pressure only when engine is stopped and radiator cap is cool enough to touch with your bare hand.Cooling System Conditioner contains alkali. Avoid contact with skin and eyes.
Table 1
Troubleshooting Test Steps Values Results
1. Make Sure the Engine is Correctly Equipped for Ambient Conditions
A. Ensure that the engine is correctly equipped for the ambient conditions.
Engine operation
Result: The engine is equipped for the ambient conditions.
Proceed to Test Step 2.
Result: The engine is not equipped for ambient conditions.
Repair: Refer to the Operation and Maintenance Manual for more information regarding equipment required for cold-weather operation.
2. Inspect the Cooling System
A. Check the coolant level.
B. Check for signs of a coolant leak.
Note: If the coolant temperature sensor is not immersed in coolant, a false reading can occur.
Engine coolant level
Result: The engine coolant level is OK.
Proceed to Test Step 3.
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.
3. Faulty Coolant Temperature Sensor
A. Check the reading of the coolant temperature on the electronic service tool. The temperature should rise steadily as the engine is warmed. Ensure that the temperature is as expected.
Faulty coolant temperature sensor
Result The coolant temperature is as expected.
Repair: A failed coolant temperature sensor has been detected. Replace the temperature sensor.
Result The coolant temperature is as expected.
Proceed to Test Step 4.
4. Check the Engine Coolant System
A. Turn the keyswitch to the OFF position.
B. Connect to the electronic service tool.
C. Start the engine.
D. Monitor the "Engine Coolant Temperature" in the status screen
Coolant temperature
Result: The coolant temperature comes up to operational temperature.
Return the unit to service.
Result The coolant temperature does not come up to operational levels.
Repair: Test the water temperature regulator. Refer to Systems Operation, Testing, and Adjusting, "Water Temperature Regulator - Test". If the test fails, replace the water temperature regulator. Refer to Disassembly and Assembly, "Water Temperature Regulator - Remove and Install".
If the fault is still present, contact the Dealer Solutions Network (DSN).