ROD 4J3732 - Caterpillar

Table 1
J1939 Code and Description Comments
4243-0
Engine Oil to Engine Coolant Differential Temperature : High - Most Severe (3) The engine oil temperature is too high or the engine coolant temperature is too low. The differential between the engine oil temperature and the engine coolant temperature has exceeded the trip point and the delay time has expired.
The alarm output is activated.
The code is logged.
4243-15
Engine Oil to Coolant Differential Temperature : High - least severe (1) The engine oil temperature is too high or the engine coolant temperature is too low. The differential between the engine oil temperature and the engine coolant temperature has exceeded the trip point and the delay time has expired.
The alarm output is activated.
The code is logged. Note: The cylinder liner and the piston assembly can be damaged by this condition.Probable Causes
Low engine coolant temperature or high engine oil temperature
Faulty temperature sensor and/or circuit
Faulty water temperature regulatorsRecommended Actions
Table 2
Troubleshooting Test Step Value Result
1. Check for Codes
A. Connect Cat® Electronic Technician (ET) to the service tool connector.
B. Look for active codes that are associated with the system for the event code.
Codes
Result: An associated code is active.
Repair: Troubleshoot any associated codes before continuing with this test.
Result:A code is active or logged.
Proceed to Test Step 2.
Result: No active codes
STOP
2. Check the Engine Oil Temperature and the Coolant Engine Temperature
A. Observe the temperature of the engine oil and the engine coolant on the control panel display.
Oil and Coolant Temperatures
Result : The oil and coolant temperatures are OK.
Proceed to Test Step 3.
Result: The oil temperature is NOT OK.
Repair: Refer to Troubleshooting, "Oil Temperature Is High".
Result: The coolant temperature is NOT OK.
Repair: Refer to Troubleshooting, "Coolant Temperature Is Low".
If problem is not resolved, proceed to Test Step 3.
3. Check the Oil and Coolant Temperature Sensors
A. Check the reading of the coolant temperature on Caterpillar Electronic Technician (ET). The temperature should rise steadily as the engine is warmed. Ensure that the temperature is reasonable.
B. Use a separate device to measure the temperatures of the engine oil and the engine coolant.
Compare the measured temperatures to the readings on the control panel display.
Oil and Coolant Temperature Sensors
Result: The temperature sensors are OK.
Proceed to Test Step 4.
Result: The temperature sensors are NOT OK.
Repair: Repair or replace the temperature sensors.
If problem is not resolved, proceed to Test Step 4.
4. Check the Water Temperature Regulators
The water temperature regulators should not begin to open until jacket water reaches opening temperature for the regulators.
A. Allow the engine to cool and then start the engine. Check the hose at the outlet for the jacket water. If the hose is warm and normal operating temperature is not achieved yet, a regulator may be stuck open.
B. If the water temperature regulators are malfunctioning, check the water temperature regulators according to Systems Operation/Testing and Adjusting, "Testing the Cooling System".
Temperature Regulators
Result: The temperature regulators are NOT OK.
Repair: Replace the water temperature regulators, if necessary.
If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer