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GMT425 speedo sensor to VSSB wires?

FellowTraveler

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OK, I am running a speed sensor in the NP241c t-case to the VSSB.
However; on the speedo sensor harness to the VSSB there is a wire coupler socket located on top of transmission case that has the same socket on each side that looks to "switch the wires from purple & green to green and purple"...through the coupler and it looks to act as just inline coupler.
I suspect this was for the 4L80e t-case HI/LOW to VSSB, am I right or, and how should I wire this up with or without coupler?
I am running a stand alone trans controller and don't need the connections to the PCM.
 
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The wires are not polarity sensitive. That double ended coupler is there so GM could use the sane harness for 2 & 4 wheel drive trucks. The transfer case harness used that double ended plug to extend the output speed sensor plug back to the transfer case output is all. Just make CERTAIN to keep the wires going from the speed sensor to the vssb as a twisted pair(at least 1 twist per inch). If you put in straight wires to it, any rf interference, magnet, or even a power wire running near it can throw it off. GM in later years even went to a twisted pair inside of a ground shielded tube.

And don't throw away that double ended jumper. They're nearly impossible to find and commonly break.
 
The wires are not polarity sensitive. That double ended coupler is there so GM could use the sane harness for 2 & 4 wheel drive trucks. The transfer case harness used that double ended plug to extend the output speed sensor plug back to the transfer case output is all. Just make CERTAIN to keep the wires going from the speed sensor to the vssb as a twisted pair(at least 1 twist per inch). If you put in straight wires to it, any rf interference, magnet, or even a power wire running near it can throw it off. GM in later years even went to a twisted pair inside of a ground shielded tube.

And don't throw away that double ended jumper. They're nearly impossible to find and commonly break.
As always FERM you are the man, a BIG THANKS goes out to you, I plan to do that ground shielded tube too.
 
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