The SCM accepts information that is needed to determine the on/off state of the engine's fuel and ignition system. The SCM accepts information from the following sources:
- Operator
- Magnetic Speed Pickup (MPU)
- Module for the pressure and temperature
- Electronic Ignition System (EIS) control
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| Illustration 1 | g00785287 |
(1) Liquid Crystal Display (LCD) (2) Switch for the display (3) "Overcrank" indicator (4) "Low Oil Pressure" indicator (5) "Overspeed" indicator (6) "Emergency Stop" indicator (7) "High Coolant Temperature" indicator (8) "Auxiliary Shutdown" indicator | |
When the SCM receives a signal to run the engine it will turn on the fuel supply and it will engage the starting motor. When the crank terminate speed is reached, the starting motor is disengaged. When the SCM receives a signal to stop the engine, it will turn off the fuel supply.
The SCM has the following features:
Cycle Crank - The SCM can be programmed for different crank-rest-crank cycles. Refer to Testing and Adjusting, "Setpoint Programming" for additional information.
2301A Speed Control - When the engine oil pressure increases past the low oil pressure set point, the SCM will increase the engine speed from idle to rated.
Cooldown - When a normal shutdown is requested, the SCM will wait the programmed amount of time before shutting off the gas valve.
Automatic Operation - While in the automatic mode, the SCM can be energized by a remote Initiate Contact (IC) signal. Upon loss of the signal from the IC, the SCM will perform a normal shutdown.
Alarm Module Communication - The SCM can transmit fault conditions and alarm conditions to an alarm module.
Power Down - When placed in the OFF/RESET position, the remote control panel (status) system will not power down until the "Crank Termination Relay (CTR)" and the "Fuel Control Relay (FCR)" are both de-energized.
Fuel Solenoid Type - The SCM can be programmed for the Energize To Run (ETR) fuel system or the Energize To Shutdown (ETS) fuel system.
Emergency Stop - If the SCM detects an emergency stop, the engine will be shutdown via ignition and fuel control.
Pressure/Temperature Module Malfunction - If the signal from the oil pressure/temperature transducer is lost or unreadable, the engine will be shutdown and a diagnostic code will be generated. The SCM can be programmed to ignore a malfunction of the transducer.
Speed Pickup Malfunction - If the SCM loses the magnetic pickup signal, the engine will be shutdown and a diagnostic code will be generated.
Liquid Crystal Display (LCD) - Symbols for the following parameters are located under LCD (1). The LCD provides a digital display of the status of these parameters. When the status of a parameter is displayed, an arrow at the bottom of the LCD points to the corresponding symbol. The display can be in metric units or English units.
| Hour meter - When the arrow points to this symbol, the hours of engine operation are displayed. |
| Engine speed - When the arrow points to this symbol, the engine rpm is displayed. |
| System battery voltage - When the arrow points to this symbol, the voltage of the electrical system's battery is displayed. |
| Engine oil pressure - When the arrow points to this symbol, the engine oil pressure is displayed. |
| Coolant temperature - When the arrow points to this symbol, the coolant temperature is displayed. |
The parameters are displayed sequentially. To lock the display onto one of the parameters, press switch (2). To resume the sequential display, press the switch again.
The LCD is also used to display diagnostic codes. A diagnostic code indicates that the system has detected a problem with a component that is associated with the status control module. When a diagnostic code is displayed, "dIAG" will be flashing on the display instead of an arrow that is pointing at a symbol. If more than one diagnostic code is present, the diagnostic codes will be displayed in sequence. Refer to Testing and Adjusting, "Diagnostic Trouble Codes" for additional information.
To clear the diagnostic codes from the LCD, turn the engine control switch to the "Off/Reset" position. The "Diagnostic Reset" switch must also be activated.
Note: For all fault conditions, if the fuel control fails to shut down the engine, the ignition system is de-energized five seconds after the fault occurs.
The status control module has six indicators (Illustration 1) that indicate engine shutdowns. The shutdowns that are associated with the indicators are described below.
| "Overcrank" - If the engine fails to start within a programmed amount of time or if the number of crank cycles are exceeded, the status control module will deactivate the starting sequence. Indicator (3) will flash. The engine control switch must be turned to the "Off/Reset" position before another attempt to start the engine can be made. |
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| "Low Oil Pressure" - There are two setpoints for low engine oil pressure. The setpoints depend on the engine rpm. One setpoint is for engine rpm that is below the oil step speed setting. The other setpoint is for engine rpm that is above the oil step speed setting. If the engine oil pressure decreases below the setpoint, the fuel to the engine will be shut off. Indicator (4) will flash. Refer to Testing and Adjusting, "Low Oil Pressure Protection - Check" for additional information. |
| "Overspeed" - If the engine rpm exceeds the setpoint for overspeed, the fuel and the ignition will be shut off. Indicator (5) will flash. |
Note: A verify button for overspeed is located on the back of the SCM. This enables a test of the overspeed protection system to be performed. Refer to Testing and Adjusting, "Overspeed Protection - Check" for additional information.
| "Emergency Stop" - Indicator (6) will flash if the "Emergency Stop" button is used to stop the engine. |
| "High Coolant Temperature" - If the coolant temperature exceeds the setpoint, the fuel will be shut off. Indicator (7) will flash. Refer to Testing and Adjusting, "High Coolant Temperature Protection - Check" for additional information. |
Note: Do not use the coolant temperature sensor to monitor the operation of jacket water heaters (if equipped).
"Auxiliary Shutdown" indicator (8) indicates that an external request was used to stop the engine. If the auxiliary shutdown is not used, the "Auxiliary Shutdown" indicator can be used as a spare indicator.
Note: Only the indicators on the status control module are reset when the engine control switch is turned to the "Off/Reset" position. Diagnostic codes must be cleared with the "Diagnostic Reset" switch.