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Hi I'm Wayne, I will help you with this,
I do not have a schematic, but the speedo sensor is located on trans near drive shaft, should have 2 wires
it is a magnetic pick up
its a 3 wire sensor
OK, some are 2 some are 3
we have no power there.We would like to know if its a 5 volt.or 12 v.
you get voltage into wire when the drive shaft spins, ,it will be 7.2 v
like I said it is magnetic , creates power when steel passes the magnet
jack up truck, unplug harness, have some in cab and put into gear , check with a volt meter
Which wire has the original volts and which is output
what color are the wires, I don't recall
Black,Red and yellow with blue stripe.
BLK, Grd, Red , power and the yellow is sensor to speedo head
Does the red have twelve volts or is there no power until the wheel turns.
no power till the drive shaft turns
Would i be able to go check and continue our chat on the matter.
Thank you sir
Hey wayne there is no power to any of the wires.
then that sensor is bad
needs to be replaced
If i jump the wire while the ignition is on what is the damage.
you will blow the speed head out
IN addition the sensor was unplug.
I read that as you wanted to jump power to sensor wires to head, this is not what your are saying
you just want to jump sensor wires ,correct
It was working fine and some one already jumped it
what,where did they jump wires
At the speed sensor harness sensor was unplugged.
OK lets start this over,
if you are getting no power out of sensor, it is bad , need to replace,
The sensor was unplugged and the wire was jumped.
Our original problem was the reverse light and some one unplugged the wrong wire.
what I am saying, if the sensor is showing no voltage unplugged it is no Good , you have to have power coming out of that to make it work, botXXXXX XXXXXne
Okay Wayne we are going to change the sensor. From one of the other trucks.we will be back appreciate your patience it is very cold here so give us a chance to replace the sensor.Thanks
We will be back.
I will be out from 11:30 to 1 Pm, doctor appointment
Is there some one else we can talk to?
Here is directions from the book to check sensor
The vehicle speed sensor is mounted to the transmission. The transmission pinion shaft rotates and generates four pulses per one rotation. The rate at which the pulses are generated indicates the vehicle speed. The vehicle speed sensor (incorporated in the speedometer) uses the pulses to control needle movement and sends vehicle speed information to the engine control module and the cruise control unit. The speedometer sends 4096 pulses per mile and the frequency indicates the vehicle speed.The speed sensor is located on the right hand side of the transmission tailhousing
To test the sensor, unplug the sensor and connect a multimeter set to AC volts. If the sensor is good, you will have an output signal that varies with the speed of the vehicle.