CARRIER 1P9663 - Caterpillar

Use this procedure to troubleshoot a low coolant pressure. Also, use this procedure if one of the following event codes is active or logged.
Table 1
J1939 Code and Description CDL Code and Description Comments
109-1
Engine Coolant Pressure : Low - most severe (3) E2112 (3)
Low Engine Coolant Pressure The engine coolant pressure is lower than expected for an extended period.
The code is logged.
109-17
Engine Coolant Pressure : Low - least severe (1) E2112 (1)
Low Engine Coolant Pressure The engine coolant pressure is lower than expected for an extended period.
The code is logged. Probable Causes
Coolant level
Leaks
Expansion tank (if equipped)
Sensor
Water pump
Heat exchanger
Oil coolerRecommended Actions
Table 2
1. Check the Coolant Level
Note: If the coolant level is too low, air will get into the cooling system. Air in the cooling system will cause a reduction in coolant flow and pressure.
A. Check the cooling system for coolant leaks.
Coolant Level
Result: The coolant level is OK.
Proceed to Test Step 2.
Result: The coolant level is NOT OK.
Repair: Determine the cause of the low coolant level. Refer to Troubleshooting, "Coolant Level Is Low" for additional information.
If the problem is not resolved, proceed to Test Step 2.
2. Check the Cooling System Hose Routing
A. Check the cooling system clamps and hoses to make sure that the clamps and hoses are installed in the proper location and the clamps are tight.
B. Ensure that there are no kinks or tight bends that may cause excessive restriction.
C. Check to make sure that the hoses are routed correctly.
Leaks or Kinks
Result: The coolant clamps and hoses are installed properly.
Proceed to Test Step 3.
Result: The coolant clamps and hoses are not installed properly.
Repair: Repair or replace the damaged cooling system component.
If the problem is not resolved, proceed to Test Step 3.
3. Check the Expansion Tank
A. Check the shunt line for a restriction. A restriction of the shunt line from the expansion tank to the inlet of the jacket water pump will cause a reduction of water pump efficiency.
B. Inspect the expansion tank for a restriction that blocks the port to the shunt line.
Note: The expansion tank may be integrated into the design of the radiator top tank and may not be separate.
Shunt Line
Result: The shunt line is properly installed and there are no restrictions.
Proceed to Test Step 4.
Result: The shunt line is not properly installed or there are restrictions.
Repair: Install the shunt line correctly or replace the line if necessary. Remove any restrictions that are found.
If the problem is not resolved, proceed to Test Step 4.
4. Check the Coolant Pressure Sensor
A. Install a mechanical pressure gauge in the coolant jacket near the coolant pressure sensor.
B. Start the engine.
C. Connect Cat® Electronic Technician (ET) to the service tool connector.
D. Allow the engine to run and record the coolant pressure on the mechanical gauge.
E. Check the coolant pressure reading at various engine speeds.
Sensor
Result: The pressure difference between the mechanical gauge and the reading in Cat ET is less than 14 kPa (2 psi).
Proceed to Test Step 5.
Result: The pressure difference between the mechanical gauge and the reading in Cat ET is