Testing the Hall sensors on a K Bike
Testing Building and using a simple test set
To find out which sensor(s) have failed you need a simple test set. All you need are the following parts, a 12v power source, three small insulated crocodile clips, wire, heat shrink tube and a 12v LED (that's an LED that's had a resistor built in to make it work from a 12v supply).
Important: Do not use a conventional bulb of any kind, it will draw too much current and damage the sensors irreparably.
Below is the test schematic for a K bike. Sensors output are on pin #2 and #5 of the sensor plug.
Any good sensor should light the LED until something metallic, like a feeler gauge, is introduced in to the sensors gap, the LED will then go out.
Any sensor that doesn't light the LED or doesn't go out when the sensor gap is obstructed is defective.
The Hall sensors are
known to fail when hot. They are rated to operate at a temperature
between -40 to +160 degrees Celsius.
following picture shows a test done on an R bike.
The K bike has a round plug as noted above