3512C Marine Auxiliary Generator Set Engines with Dynamic Gas Blending Caterpillar

Use this procedure in order to troubleshoot high intake manifold air temperature. Also, use this procedure if one of the following diagnostic codes is active or easily repeated.

Table 1

Diagnostic Codes Table
J1939 Code and Description	Conditions which Generate this Code	System Response
105-15 ine Intake Manifold #1 Temperature : High - least severe (1)	The intake manifold air temperature is above the trip point for the programmed delay time.	The code is logged.
105-16 Engine Intake Manifold #1 Temperature : High - moderate severity (2)	The intake manifold air temperature is above the trip point for the programmed delay time.	The code is logged. Engine power is derated.
105-0 Engine Intake Manifold #1 Temperature : High - most severe (3)	The intake manifold air temperature is above the trip point for the programmed delay time.	The code is logged. Engine power is derated.

Probable Causes

• Diagnostic codes

• High inlet air temperature

• High coolant temperature

• Air inlet restriction

• Exhaust restriction

• Engine overload

• Aftercooler problem

Recommended Actions

Note: The procedures have been listed in order of probability. Complete the procedures in the order of the listed test steps.

Table 2

Troubleshooting Test Step	Value	Result
1. Check for Active Codes and Logged Codes A. Connect Caterpillar Electronic Technician (ET) to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools", if necessary. B. Monitor the diagnostic codes on Cat ET. Check for active or logged diagnostic codes. Specifically check for codes that could be associated to high intake manifold temperature. Refer to the histogram information for engine derates in Cat ET. Note: Wait at least 30 seconds in order for diagnostic codes to become active. C. If the histograms contain derates and no diagnostic codes are present, then the engine is operating normally.	Codes	Result: A code is active or logged. Repair: Troubleshoot any codes before continuing with this procedure. Verify that the repair eliminated the problem. Reset the histogram. Result: A code is not active or logged Proceed to Test Step 2.
2. Check for High Inlet Air Temperature A. Determine if the inlet air temperature is within the design specifications for the cooling system.	Temperature	Result: The inlet air temperature is OK. Proceed to Test Step 3. Result: The inlet air temperature is NOT OK. Repair: Determine the cause of the high inlet air temperature and correct the problem. Verify that the repair eliminated the problem.
3. Check for High Coolant Temperature Refer to Troubleshooting, "Coolant Temperature Is High".	Temperature	Result: The coolant temperature is OK. Proceed to Test Step 4. Result: The coolant temperature is NOT OK. Repair: Determine the cause of the high coolant temperature and correct the problem. Verify that the repair eliminated the problem.
4. Check for Inlet Air Restriction Refer to Troubleshooting, "Inlet Air Is Restricted". Note: A restriction of the inlet air can cause high cylinder temperatures. High cylinder temperatures can cause a high coolant temperature.	Restriction	Result: The inlet air is not restricted. Proceed to Test Step 5. Result: The inlet air is restricted. Repair: Determine the reason for high inlet air restriction and repair. Verify that the repair eliminated the problem.
5. Check for Exhaust Restriction A. Measure the exhaust restriction during engine operation with a load. For data that is specific to your engine, refer to the Technical Marketing Information (TMI). Note: A restriction in the exhaust system can cause high cylinder temperatures. High cylinder temperatures can cause a high coolant temperature.	Restriction	Result: The exhaust restriction measures OK. Proceed to Test Step 6. Result: The exhaust restriction measurement is NOT OK. Repair: Determine the reason for high exhaust restriction and repair. Verify that the repair eliminated the problem.
6. Check for Engine Overload A. Determine if the engine is being overloaded. Note: The engine may be running in the lug condition. When the load that is applied to the engine is too large, the engine will run in the lug condition. When the engine is running in the lug condition, engine rpm does not increase with an increase of fuel. This lower engine rpm causes a reduction in coolant flow through the system.	Load	Result: The engine is not being overloaded. Proceed to Test Step 7. Result: The engine is being overloaded. Repair: Reduce engine load to an acceptable limit. Verify that the repair eliminated the problem.
7. Check for a High Inlet Temperature for the Aftercooler A. Compare the temperature of the coolant to the regulated temperature.	Temperature	Result: The inlet temperature of the aftercooler is OK. Proceed to Test Step 8. Result: The inlet temperature for the aftercooler is NOT OK. Repair: Determine why the inlet temperature of the coolant is high and correct the problem. Verify that the repair eliminated the problem.
8. Check for Insufficient Flow of Inlet Air Through the Aftercooler A. Determine the pressure differential of the inlet air across the aftercooler.	Restriction	Result: The pressure differential is NOT OK. Repair: Clean the aftercooler.

If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).