OMEX 200 Series - Throttle Position Sensor (TPS)

2.2 Throttle Position Sensor (TPS)
The addition of a throttle position sensor allows varying ignition timing with changes in engine load;
similar to a ‘vacuum advance’. This sensor must be placed on the end of the throttle spindle.
Pin-outs
If you have purchased a throttle position sensor from Omex, then the pin-outs for your sensor can be
found on the information sheet with the sensor. If you are using an unknown sensor then you will need
to test the potentiometer to find this information.
Allocate the sensor terminals with numbers 1,2,3. With the sensor disconnected from any wiring use a
multimeterontheresistancesetting(kΩ)tomeasuretheresistancebetweeneachoftheterminalswith
the throttle in an approximate closed position and then with the throttle in an approximate open position
(the absolute position is not important).
Between two of the terminals the resistance will not change as the throttle is opened. This tells us that
the remaining terminal is the signal (Omex orange cable). From the remaining two terminals, one of
them will have a resistance to the signal that is lower when throttle open than when throttle closed, this
is the 5V reference voltage terminal (Omex pink cable). The last terminal must therefore be the sensor
0V (Omex grey cable).
Example;
When the throttle position is moved from closed to open, the resistance does not change between 1
and 3. Therefore, 2 must be the signal (Omex orange). 3 has the lower resistance to the signal with the
throttle open and so must be the 5V (Omex pink), leaving 1 to be the sensor 0V (Omex grey).
OMEM200 Installation Manual 2v10
8
Closed
5200
4300400
1 2 3
Open
5200
4004300
1 2 3