Cheers Spuggy,
Yes as soon as both you and Wazzz explained that's it actually a reed switch and not a coil type sensor, I understood the kind of measurements I could do to establish if there is on off continuity when the magnets are pulling the switch closed etc, yes I agree its not easy to do these tests on your own, but I have a plan!
I will let you know how it goes.
Ant.
Quote:
Originally Posted by spuggy
The "sensor" is a reed switch. It's open (infinite ohms) when there's no magnet under it, and closed (no/low resistance) when there is. One side is power, the other is a square wave fed into the speedo, which counts the pulses.
- Get a helper to turn the axle or wheel. Or roll the car - doesn't need to be in gear.
- Measure continuity.
But if the wheels are off the ground and you have an open diff, make sure to turn the side with the sensor/carrier disk...
Turning the axle and randomly measuring continuity statically is the hard way to do this.
Dynamic test is much better & easier - one full turn and you'll know exactly what's going on.
Rolling diameter of the tire is ~25", so the car doesn't need to move very far. When I was calibrating my Yellow Dog, I checked the sensor for correct operation by sticking a leg out the door and scooting the car backwards Flintstones style. |