| Event Code | ||
|---|---|---|
| Code and Description | Conditions which Generate this Code | System Response |
| E194(2) High Exhaust Temperature | The exhaust temperature that has been calculated by the Electronic Control Module (ECM) is above the trip point temperature. | The engine is derated. The code is logged. |
The activation of this event indicates that a high virtual exhaust temperature has been calculated by the ECM. This temperature is calculated with maps that utilize intake manifold temperature, atmospheric pressure, and engine speed as factors.
High intake manifold air temperature, high altitude operation, and high engine loads can cause the exhaust temperature to increase to a level that may damage the exhaust valves and other components of the exhaust system.
When this event occurs, the ECM derates the engine in order to reduce the exhaust temperature. This action helps to protect the components of the exhaust system from damage.
Probable Causes
Operating Conditions
- High altitude operation
- Above normal loads
Aftercooler
- Restrictions in the aftercooler
Air Inlet and Exhaust System
- Restriction in the air inlet and exhaust system
Voltage Supply to the Atmospheric Pressure Sensor
- Absence of power to the atmospheric pressure sensor
Recommended Actions
High Altitude Operation
Consider high altitude operation of the engine when you troubleshoot this event code. High altitude operation can cause the code to be generated. This action is normal.
Above Normal Loads
Interview the operator, when possible. Determine if the engine is being operated under heavy load. Ensure that the engine is being operated at the proper engine speed.
Air Inlet and Exhaust System
- Check the air filter restriction indicator for a plugged filter. If necessary, service the engine. Refer to the Operation and Maintenance Manual.
- Check the air inlet and exhaust system for restrictions and/or leaks. Refer to Systems Operation/Testing and Adjusting.
- Check flame arrester for blockage on ATEX engines.
Restrictions in the Aftercooler
The intake manifold air temperature can increase if the flow through the aftercooler is restricted. Thoroughly check the aftercooler for restrictions. Ensure that the flow of air or coolant through the aftercooler is adequate.
Absence of Power to the Atmospheric Pressure Sensor
If the atmospheric pressure sensor is not being powered by the 5 volt supply. Then the output of the sensor may float to a value that is interpreted by the ECM as a high altitude condition. The ECM receives the erroneous value of altitude and the ECM derates the engine. Ensure that the 5 volt supply is present at the harness connector for the atmospheric pressure sensor.