BOLT 5B0841 - Caterpillar

Conditions Which Generate This Code:The Electronic Control Module (ECM) detects inlet air temperature that exceeds the trip point temperature. Information on default settings and ranges for this event can be found in Troubleshooting, "Event Codes".System Response:The ECM will log the event.
There are no performance effects.Test Step 1. Check the Engine's Air Inlet and Exhaust Systems
Check for a restriction in the air inlet system. A restriction of the air that is coming into the engine can cause high cylinder temperatures. High cylinder temperatures cause higher than normal temperatures in the cooling system.
Check for a restriction in the exhaust system. A restriction of the air that is coming out of the engine can cause high cylinder temperatures.Results:Continue to the next test step.Test Step 2. Check for an Extreme Operating Environment
Consider high ambient temperatures. When ambient temperatures are too high for the rating of the cooling system, there is not enough of a temperature difference between the ambient air and coolant temperatures.
Consider high altitude operation. The cooling capability of the cooling system is reduced at higher altitudes. A pressurized cooling system that is large enough to keep the coolant from boiling must be used.
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.Expected Result:A thorough inspection of the engine revealed a problem.Results:
OK - There is a problem with the engine.Repair: Repair the problem. Ensure that the repair eliminates the problem.STOP