91 speedometer

[78-5.3]

im trying to work out what i need to use for my speedo there seams to be 3 coppers strands going into the speedo head for the elec speedo now im useing this speedo in my 78 truck!!! anyone done this conversion please help shed some light !!!

[68 TT]

Originally Posted by 78-5.3

im trying to work out what i need to use for my speedo there seams to be 3 coppers strands going into the speedo head for the elec speedo now im useing this speedo in my 78 truck!!! anyone done this conversion please help shed some light !!!

One will be the ground, one the ignition on power source and the other one the connection from the PCM telling it what to do.

I haven't found a wiring diagram that shows the connector pinout for the electronic speedo cluster so I can't tell you for sure which circuit is for what.

Can you post a pic of the back, maybe we can trace the circuits and find some common connection points I can identify with what I have identified on the older clusters. The gauges other than the speedo should still all be connected with the same wire configuration and colors.

[78-5.3]

i noticed on the cluster there is 2 tan wire splice together going to fuel gauge seams to jump on the other side of the connector !!!

[Russell]

Hey -- I don't have enough time to type out a response for you here right, but please send me an email at Russell@ZieglerDigital.ca and I'll send you some detailed information on installing an electric speedo in your truck tomorrow evening

I put one into my 80 GMC, and I have pinouts for the DRAC, info on how to calibrate for tire size etc