I need to know what the order of the three wires going into the yellow box are. Pic would be nice...really need it, doing this right now, cant find spare buffer... Thanks

 

The yellow speed buffer box has a red, black, and green wire going into it on one end. These go the the optical emitter / detector.

The other end of the speed buffer box has the flex harness plugged into it. There are three traces (wires) going to the buffer. The trace closest to the bottom of the cluster is the ground connection, the middle trace is the VSS output signal, and the trace closest to the top of the cluster is +12 volt ignition power.

Tim

 

Thanks Tim.... still pretty blurry.. I dont really get the order...could you clear it up a bit?

 

Sure, if you hold the cluster upright with the back facing you, the speed buffer box should be on the left. There is a flexible circuit card, or "flex harness" that plugs into the left hand side of the speed buffer box. There are three traces, or "wires" on the flex harness. One is toward the top, one in the middle, and one toward the bottom of the three wire flex harness going to the speed buffer.

Tim

 

Is the vss on the insturment cluster or is it mount over by the computer?

 

The VSS is on the back side of the instrument cluster up through '89. In '90 the VSS functionality was moved to the ECM along with the speedo going to electronic sensor drive instead of cable drive.

Tim

 

The VSS buffer is on the back side of the instrument cluster, up through '89. In '90 GM went to an electronic sensor driven speedo & the VSS buffer functionality was moved to the ECM.

Tim

 

There is also a setup available with a VSS buffer mounted on the ECM. This is how it was in the 86 T/A i'm pulling parts for my swap from.

This page has the pinout info for the buffer on this setup.
http://www.angelfire.com/mt/psh/speedo.htm

Hope this helps

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82 T/A 305/TH350; soon to be 350/T-5