Does anyone know what voltage it would take to make the speed sensor motor turn? I tried hooking it up to a 9 volt battery and it wouldn't turn.. I'm trying this because I want to know for sure if my speed sensor is bad. Is there a definite way to test if it is bad??

 

The speed sensor is connected to the trans. So you either have to remove it or turn the wheels and see how much volts it produces.

 

You could also connect a drill to the shaft of the sensor and check that you are getting a voltage signal from the sensor.

Brent.

 

Does anyone know voltage ouput? I removed mine and spin by hand and get maybe 10 milivolts. Is there a spec anywhere? My haynes & chiltons manuals don't even show a speed sensor!

 

I tried to connect it to a drill but either the drill wasn't spinning fast enough, or i was using a wrong tester. I was using a battery tester with variable settings, 1.5 volts or 9 volts. It didn't do anything on either setting. I wouldn't think the speed sensor would need to produce any more than 9 volts, but i could be wrong or my speed sensor is really busted.

 

Sorry, don't know what the voltages are supposed to be, reasonably low though from memory. If you use a multimeter set on DC volts you should eiter get a reading or none.

I thought I had a problem with the sensor, tried this trick found that it was producing a signal. The fault was in the speedo unit in the dash.

Brent

 

well it's probably broken NOW!
j/k
generally it's not a good idea to hook voltage up to stuff unless you're sure it's made to accept voltage....personal experience. Of course, 99% of the time a 9 volt battery isn't gonna hurt anything in your car.