So i copied most of this out of my personal thread, but personally i think it's valuable to anyone working with the 92-94 platform. I've got a lot of research and time wrapped up in this, so i figured i'd share.
This could help anyone from Cummins swaps, to duramax swaps, to transmission swaps, etc.
Basically this is going to assist in using the Dakota Digital SGI-5E speedometer interface with an VSS output speed different than 128,000 ppm sinewave.
These are all things the SGI-5E can do.
Did some research. (for my application, dodge 47RE behind a cummins)
The 47Re uses a three wire sensor sends 8000 ppm output square wave signal to the speedometer gauge on the Dodge,
Three wires,
Orange: 5v Supply
White/Orange - VSS Signal
Blue/Black - Ground
The GM 4L80E sensor uses two wire sensor that sends a 128,000 ppm output sine wave signal to the VSSB.
purple/green wires that plugs into the VSS.
The wires then feed into the VSSB (Vehicle speed sensor buffer: pictured below)
The VSSB then transmits the signals accordingly and sends them to each application.
Plug #824 sends vehicle speed to speedo: (4000 ppm signal) - Light blue / black wire
Plug #437 sends vehicle speed to PCM: (signal unknown) - brown wire
Plug #821 (purple/white) vehicle speed input from VSS sensor (green/black) - 128,000ppm input signal to VSSB (one of #821/#822 is a low high SINEWAVE signal)
Plug #250 12 volt ignition - brown wire
Plug #696 goes to the rear wheel ABS (128000 ppm signal) - dark blue wire
Plug #450: ground - black/white wire
Plug #822 vehicle speed input from VSS sensor (green/black) - 128,000ppm input signal to VSSB (one of #821/#822 is a low high SINEWAVE signal)
Plug #818 goes to cruise: (2000 ppm signal) - red/white wire
Basically after discovering all of this, i called the Dakota digital guys. I tried to use #7 on the Dakota digital instructions to convert the 8000 ppm signal from the dodge VSS to a 128,000 ppm speedo for the GM VSS wires (Purple/white & Green and black) - former VSS wires.
I was unable to get the speedometer gauge to move even a little.
So i reverted to mode #4 on the Dakota digital. Figured i would use the 4000 ppm output to the speedometer gauge and the 2000ppm output to the cruise. I did not not worry about ABS since it's just rear wheel ABS that i don't even think hardly does anything.
So essentially what I've done is used the SGI-5E as the new VSS buffer, and ran the dodge VSS wires into the SGI-5E (located in the glovebox) as the new VSS using the original VSS wires. Basically I've replaced the VSS with a programmable VSS that i can easily tune or change based on gear/tire sizes.
This weekend i will use a Ulysses GPS Speedometer on my phone to dial in the SGI-5E.
I'm not saying that the SGI-E cannot transmit the signal into the purple/green GM VSS wires.. i just could not figure out how to do it. and found this to be fairly simple and relatively harmless.
ATTENTION: THIS IS JUST FOR THE 92-94 TRUCKS: Between DRAC, and VSSB, things changed year by year. The diagrams are out of my 1993 Chevy C/K Technicans Wiring diagram book, for trucks outside of 92-94 i would NOT recommend using any of this information. Use alldata or an equivalent source to obtain the wiring diagrams for your year. The rest of this information was obtained through various internet searches.
Make sure you do your research prior to messing with wires to avoid damage to your vehicle.
This could help anyone from Cummins swaps, to duramax swaps, to transmission swaps, etc.
Basically this is going to assist in using the Dakota Digital SGI-5E speedometer interface with an VSS output speed different than 128,000 ppm sinewave.
These are all things the SGI-5E can do.
You must be registered for see images attach
Did some research. (for my application, dodge 47RE behind a cummins)
The 47Re uses a three wire sensor sends 8000 ppm output square wave signal to the speedometer gauge on the Dodge,
Three wires,
Orange: 5v Supply
White/Orange - VSS Signal
Blue/Black - Ground
You must be registered for see images attach
The GM 4L80E sensor uses two wire sensor that sends a 128,000 ppm output sine wave signal to the VSSB.
purple/green wires that plugs into the VSS.
You must be registered for see images attach
The wires then feed into the VSSB (Vehicle speed sensor buffer: pictured below)
You must be registered for see images attach
The VSSB then transmits the signals accordingly and sends them to each application.
You must be registered for see images attach
Plug #824 sends vehicle speed to speedo: (4000 ppm signal) - Light blue / black wire
Plug #437 sends vehicle speed to PCM: (signal unknown) - brown wire
Plug #821 (purple/white) vehicle speed input from VSS sensor (green/black) - 128,000ppm input signal to VSSB (one of #821/#822 is a low high SINEWAVE signal)
Plug #250 12 volt ignition - brown wire
Plug #696 goes to the rear wheel ABS (128000 ppm signal) - dark blue wire
Plug #450: ground - black/white wire
Plug #822 vehicle speed input from VSS sensor (green/black) - 128,000ppm input signal to VSSB (one of #821/#822 is a low high SINEWAVE signal)
Plug #818 goes to cruise: (2000 ppm signal) - red/white wire
You must be registered for see images attach
Basically after discovering all of this, i called the Dakota digital guys. I tried to use #7 on the Dakota digital instructions to convert the 8000 ppm signal from the dodge VSS to a 128,000 ppm speedo for the GM VSS wires (Purple/white & Green and black) - former VSS wires.
I was unable to get the speedometer gauge to move even a little.
So i reverted to mode #4 on the Dakota digital. Figured i would use the 4000 ppm output to the speedometer gauge and the 2000ppm output to the cruise. I did not not worry about ABS since it's just rear wheel ABS that i don't even think hardly does anything.
So essentially what I've done is used the SGI-5E as the new VSS buffer, and ran the dodge VSS wires into the SGI-5E (located in the glovebox) as the new VSS using the original VSS wires. Basically I've replaced the VSS with a programmable VSS that i can easily tune or change based on gear/tire sizes.
This weekend i will use a Ulysses GPS Speedometer on my phone to dial in the SGI-5E.
I'm not saying that the SGI-E cannot transmit the signal into the purple/green GM VSS wires.. i just could not figure out how to do it. and found this to be fairly simple and relatively harmless.
ATTENTION: THIS IS JUST FOR THE 92-94 TRUCKS: Between DRAC, and VSSB, things changed year by year. The diagrams are out of my 1993 Chevy C/K Technicans Wiring diagram book, for trucks outside of 92-94 i would NOT recommend using any of this information. Use alldata or an equivalent source to obtain the wiring diagrams for your year. The rest of this information was obtained through various internet searches.
Make sure you do your research prior to messing with wires to avoid damage to your vehicle.
