How to repair your own speedo sender!
It seems that most sensor failures are due to moisture entering the unit and causing the Hall sensor to fail.
The retail price of the sender unit p/n 4GY-83755-01 in October 2010 was £119.98 inc VAT so a repair is worthwhile persevering with!
The following details are courtesy of Сергей Трофимов who emailed me the circuit diagram and picture along with advice as to a sensor that would do the job well. Many thanks Sergey!
The Hall sensors are relatively cheap and easy to obtain - look here for an example that I have used and works well. In case the link breaks go to the Conrad Electronic website and look for
However, Sergey says that any Hall sensor should be suitable as they are all basically the same. For example, if you have a dud PC fan it is likely that you could re-use its sensor.
This is a schema of the pickup and a repaired example.
The wires are:
Yellow - out
Blue - +5v
Yellow/Black - ground
I confess that my eyesight, soldering skills and courage were not up to the task and I managed to find a skilled person to do it for me!
5 December 2010
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- Yamaha TTR250 parts & accessories guide
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