Use this procedure in order to troubleshoot a high inlet air temperature. Refer to Troubleshooting, "Event Codes" for information about event codes and the default trip point for this code. You must access the monitoring system on AVSpare Electronic Technician (ET) in order to view the current trip point for this code.
|Event Code    |
|Code    ||Conditions which Activate the Code    ||System Response    |
|E025(2) High Inlet Air Temperature Derate    ||The inlet air temperature has exceeded the programmed trip point for the specified delay time.    ||The code is logged.
Engine power is derated.
|E027(1) High Inlet Air Temperature Warning    ||The inlet air temperature has exceeded the programmed trip point for the specified delay time.    ||The code is logged.    |
- High ambient air temperature
- High coolant temperature
- High inlet air restriction and/or high altitude
- Faulty inlet air temperature sensor and/or circuit
High Ambient Air Temperature
Determine if the ambient air temperature is within the design specifications for the cooling system.
Determine the cause of the high air temperature. Modify the inlet air system in order to supply intake air that is within specifications, if necessary.
High Coolant Temperature
Check for a high coolant temperature for the engine.
Refer to Troubleshooting, "Coolant Temperature Is High".
High Inlet Air Restriction and/or High Altitude
When inlet air pressure is low, the turbocharger works harder in order to achieve the desired inlet air pressure. This increases inlet air temperature.
Measure the inlet air pressure while the engine is operating under load. For specific data, refer to the Technical Marketing Information (TMI) for your engine.
Inlet Air Restriction
Check for plugged air filters. Check for obstructions to the air inlet.
Replace the air filters and/or remove the obstruction from the air inlet.
Confirm that the settings for the engine are correct for operation at the altitude of the engine installation.
Faulty Inlet Air Temperature Sensor and/or the Circuit
Allow the engine to cool. Remove the sensor from the engine. Use Cat ET to check the status of the "Engine Coolant Temperature" parameter. Compare the reading to the ambient air temperature. If the sensor is OK, the readings will be approximately equal.
If the readings are not approximately equal, switch the suspect sensor with a sensor that is known to be good. Compare the reading of the good sensor to the ambient air temperature. Replace the suspect sensor, if necessary.