The Electronic Control Module (ECM) monitors engine operation. If a parameter extends outside an acceptable range, the ECM will initiate action. The ECM can cause a warning to occur. The ECM can derate engine power. The ECM can cause an engine shutdown to occur. Not all of the actions are available for all parameters.
The AVSpare Electronic Technician (ET) can be used to select the ECM response. Cat ET can be used to program the level of engine monitoring and the delay times.
Separate timers are used in the ECM for each response that is associated with a parameter. Once the trip point is exceeded for an action, the timer for that action is started. For example, if the high coolant temperature warning is set to
Use care when you program the trip point and the delay times. The resulting ECM response must be correct for the application. If the legal range is not exceeded, the engine monitoring system will accept any setting.
If the trip point for a shutdown is lower than the trip point for a warning, the engine will shut down. The warning will not be activated.
Once a parameter has exceeded the trip point the parameter must drop a certain amount below the trip point before the ECM response will end.
If a warning is programmed to
Parameter | Hysteresis |
ECM Voltage | 2 VDC |
Oil Pressure | |
High Coolant Temperature | |
Low Coolant Temperature | |
Overspeed | 100 rpm |
Air Inlet Restriction | Latched |
Altitude | N/A |
High Exhaust Temperature | |
Oil Filter Differential Pressure | |
Fuel Filter Differential Pressure | |
Crankcase Pressure | |
Aftercooler Water Temperature | |
Note: The following tables are examples. The values may have changed. Use Cat ET to determine the actual defaults and the specific configuration.
Programmable Monitoring System | ||||||
Parameter | ECM Response | Default Trip Point | Default Delay Time | Limits | ||
Range for Trip Point | Delay Time | |||||
Low | High | |||||
Low System Voltage | On/Off | |||||
Warning | 20 VDC | 10 Seconds | 20 VDC | 22 VDC | 1 to 30 seconds | |
Low Oil Pressure | On/Off | |||||
Warning | (1) | 4 Seconds | N/A | 1 to 15 seconds | ||
Shutdown | (1) | 9 Seconds | N/A | 1 to 15 seconds | ||
High Coolant Temperature | On/Off | |||||
Warning | |
5 Seconds | |
|
1 to 60 Seconds | |
Derate | |
30 Seconds | |
|
1 to 60 Seconds | |
Shutdown | |
5 Seconds | |
|
1 to 60 Seconds | |
Low Coolant Temperature | On/Off | |||||
Warning | |
5 Seconds | |
|
1 to 60 Seconds | |
Engine Overspeed | On/Off | |||||
Warning | Application Dependent | 0 Seconds | 1200 rpm | 2400 rpm | 0 to 5 Seconds | |
Shutdown | Application Dependent | 0 Seconds | 1200 rpm | 2400 rpm | 0 to 5 Seconds | |
Inlet Air Restriction Pressure | On/Off | |||||
Warning | |
5 Seconds | |
|
1 to 60 Seconds | |
Derate | |
5 Seconds | |
|
1 to 60 Seconds | |
Altitude | On/Off | |||||
Derate | |
0 | |
|
N/A | |
High Exhaust Temperature | On/Off | |||||
Warning | |
5 Seconds | |
|
1 to 60 Seconds | |
Derate | |
5 Seconds | 1 to 60 Seconds | |||
Oil Filter Differential Pressure | On/Off | |||||
Warning | |
5 Seconds | |
|
1 to 60 Seconds | |
Fuel Filter Differential Pressure | On/Off | |||||
Warning | |
5 Seconds | |
|
1 to 60 Seconds | |
Crankcase Pressure | Off | |||||
Warning | |
3 Seconds | |
|
1 to 60 Seconds | |
Derate | |
10 Seconds | |
|
1 to 60 Seconds | |
Shutdown | |
3 Seconds | |
|
1 to 60 Seconds | |
Aftercooler Water Temperature | On/Off | |||||
Warning | |
5 Seconds | |
|
1 to 60 Seconds | |
Derate | |
5 Seconds | |
|
1 to 60 Seconds | |
Shutdown | |
5 Seconds | |
|
1 to 60 Seconds |
(1) | Refer to the oil pressure map. |
Note: The engine monitoring system is enabled after the engine is started. The ECM delays monitoring some parameters at start-up. The delay is designed to eliminate false warnings. The following parameters have a delay at start-up.
- The delay for low engine oil pressure is ten seconds.
Illustration 1 | g00994007 |
Oil pressure map |
Most active engine derates that occur are activated when the associated parameter is out of the specified range. When the parameter returns to normal operation, the active engine derate is disengaged. There is one exception for air filter restriction, the active engine derate is latched until the ECM is powered down.