Speed control switches
Item | Description |
1 | "ON" button Comments: |
2 | "OFF" button |
3 | "RES" button |
4 | "SET+" button |
5 | "SET-" button |
The cruise control buttons are non-locking push buttons. They are connected to the coil spring via a hard-wired 9-pin plug connection.
The cruise control buttons operate according to the resistance bridge circuit principle. The buttons receive a 5 Volt reference voltage. When operated, each button passes a particular voltage to the GEM. The GEM measures this voltage and from it determines which button has been pressed.
The operation of the cruise control buttons can be checked by a simple measurement of the resistance between pin 4 and pin 5 at the coil spring 9-pin connector. A change of resistance must occur when a button is pressed.