PANEL 3702246 - Caterpillar

Ether Injection Control
Ether Injection Control On some machines the ether injection control provides the engine oil pressure signal.The ether injection control provides a circuit to ground when the engine oil pressure is above a specified value. This grounded signal tells the engine overspeed control that the engine is running. The operator monitor also uses the signal.The location of the ether injection control (if equipped) is: OHT's - in rear compartment of cab.D11N - in compartment on left side of cab.994 - in the electrical controls compartment.Engine Oil Pressure Switch
Engine Oil Pressure Switch - Rear Of Engine Block (776B And 777B)The engine oil pressure switch provides a circuit to ground when the engine oil pressure is above a specified value. The switch is used by the engine overspeed control to determine that the engine is running. The engine oil pressure switch also connects to the operator monitor. The engine oil pressure switch is located on the right rear side of the engine block.Warning Indicators
The warning indicators are not the same on all machines. D11N's and 994's have a warning lamp. OHT's have a warning lamp and a warning horn.Warning Lamp
Warning Lamp Location - 776B And 777BThe warning lamp is activated by the engine overspeed control. The lamp provides a visual warning to the operator. The warning lamp is mounted next to the test switch on the front dash.Warning Horn
Warning Horn Location - OHT OnlyThe warning horn is only used on off highway trucks (OHT). The warning horn is activated by the engine overspeed control to provide an audible warning to the operator. The warning horn operates at the same time as the warning lamp. The warning horn is mounted in the cab under the front dash to the left of the steering column.Functional Operation
Engine Overspeed Control
(1) Diagnostic Lamp #1. (2) Diagnostic Lamp #2. (3) Diagnostic Lamp #3. (4) Diagnostic Lamp #4.Power Up Sequence
When the disconnect switch is ON and the machine key switch is turned to "RUN" or "START" position, the engine overspeed control powers up (turns on). Red diagnostic lamp #4 (4) on the engine overspeed control will flash rapidly for not longer than two seconds. During this time the control module is testing itself internally. After this test, all four diagnostic lamps (1), (2), (3) and (4) will alight for four seconds. This is known as the lamp test. When the lamp test is completed the engine overspeed control goes to normal mode. Also see Control Self Test in the Testing And Adjusting section.Normal Mode Operation
During normal operation the system continuously monitors the engine speed signal, the oil pressure signal, the test switch (if equipped) and the machine harness code. No alarm is sounded in this state. The system changes from this state during one of the following conditions:* If the test switch (if equipped) is depressed, the system enters the OPERATOR TEST MODE.* If engine speed exceeds the defined limit, the system enters the ALARM MODE.* If an invalid harness code exists, the system enters the