As a result of a new rally computer that I have, I needed to have a wheel sensor fitted with a 2-wire sensor. In addition, because I am an itinerant rally navigator, I need to be able to install the equipment in various cars depending upon whom I am navigating for. Therefore I needed an easily and quickly installed external style wheel sensor. I could not find what I needed commercially, therefore I decided to build one myself. The result is shown below.
My 2-Wire External Wheel Sensor
I started off with an enclosed 2-inch square aluminum box. I had to drill several holes in the box to build the wheel sensor. The small box size has its advantages once the unit is finished, but the tight size made the building of the unit difficult at times.
I Started Out With A 2-Inch Aluminum Box
A main component of the unit is the small flanged wall bearing with a 3/8-inch center hole. I installed a 3/8-inch threaded bolt through the bearing which will be used to affix the wheel sensor to my custom wheel mounting plate.
3/8-inch Flanged Wall Bearing Was A Tight Fit
The other major component is the sensing device. This sensing device had its mounting complications because the thread size was 12 x 1.0mm. In the USA finding large diameter nuts with a fine 1.0mm thread was not easy. It turned out that I had to modify the nuts that I did find in order to fit the “jam” style nut that I needed for the unit.
Test Fitting The Sensor In The Sensor Box
The 12 x 1.0 nuts that I found were 10mm long. That was too long for this installation therefore I had to cut the nut into a much shorter length. This cutting process is shown below.
Cutting A Nut In Half
Once the nut was cut in half I was able to complete the building of the unit. I installed two small rare earth magnets on the rotating bearing. Using the 12 x 1.0 nuts I was able to mount the sensing unit with the desired proximity distance from the rare earth magnets. I installed two rare earth magnets which will result in two pulses of the wheel sensor for each rotation of the wheel.
Installed Interior Of The External Wheel Sensor
The image below, while it shows my 3-wire EZ Pulse wheel sensor, illustrates how the new external 2-wire wheel sensor will be mounted on a wheel.
Typical External Mounted Wheel Sensor
If you have any comments or questions about this post or the wheel sensor, then you can leave a comment below or you can send me a private email message at the following address: shanna12 at comcast dot net