Hey guys. I bought an aftermarket Autometer speedometer cause my stock one broke. The new speedo I got is electronic. Its not cable driven. There are 2 wires I've gotta hook up to get the speedo to work. The first wire is the signal wire. The instructions say to hook this wire up to the postive side of the speedo sensor. The other wire hooks up the the PCM/computer to the VSS output. This will provide a buffered VSS signal to the computer for the cruise control to work. My only problem is I don't know where to hook these 2 wires on my truck. I have a 1991 Chevy S10 2.8 V6. Check out the pics below.
Here are wiring diagrams out of my Haynes repair manual.


I've got the computer pulled out to attach the wires.



Any help would be appreciated. Thanks... Andy
SPEED SENSE|GREEN / WHITE |4 |ECM *3
*3 The ECM on the 4.3 litre motor is located on the drivers side inner fender. The ECM on the 2.2 litre motor is located on the passengers side inner fender.
Try that but thats from a latter chevy s10.
i'd look for a blue/black around the transmission, thats where your speed sensors is. Does it state anywhere wher the buffer is located?
I think the wiring is different on that 4.3. I know where the sensor is located. Its at the tail of the tranny. But I don't know what is positive or negative. You can flat out cut off the stock wiring off the speedo sensor to the computer. Connect one side to ground and the other to the speedo. This works but the cruise control won't work and the service light comes on cause the ECU isn't getting a reading on how fast you're going. I think the buffer is a little white box attached to the ECU box. Look at the pics above.
Here's a pic of the back of the old speedo that doesn't work.

The blk/light green wire and the PURPLE / white wires go to the sensor on the tranny.
Andy, what I would suggest doing is leaving the wires from the speed sensor alone. Try using the brown wire from the VSS buffer as your signal, and leaving the output from your aftermarket speedo unconnected. GM vehicles have separate signals for the cruise and speedometer, so the output shouldn't be necessary. If the brown wire doesn't work, try the lt. blue/black from the VSS buffer. I think both of those supply a 4000 pulse per mile output.
-------------
C Renner's Auto Electronix
My service is cheap, quick, and good - pick any two

Sweet I'll try this. But will the cruise control still work ?