S10 Digital Dash install


Money pit
Hey all! I'm finally getting around to writing this all up. At the time of this post, I still need to wire up the water temp and oil pressure gauges, however I'm in no hurry as I still have my Autometers installed. I'm super happy with how this turned out. It is a great swap for the budget and really looks at home. Below is what it turned out like. Also check out the video:


Part 1. Finding the parts for the swap.

Below is a list of everything you will need and where to get it. Before we start, let me share a couple of shortcomings about this swap. First, the odometer reading is on a chip, so you are stuck with whatever shows up on there. Second, if you want to keep the English / Metric, Trip Odometer / Reset buttons, you will need to relocate them somehow. For me, I just took that piece apart and left the bare board in there. If I need to reset anything, I pop off the bezel to get to it. Not really a big deal, but I'll improve it some other time.

The Cluster:

These were found certain in '89 - '94 S10 Blazers with 4.3 liter motors only. If you want one, it will be best to start hitting the junkyards. There are a couple differences between them. The biggest difference is the tachometer. TBI Blazers had a 5500 RPM tach. The Vortec DFI equipped Blazers had the 6500 RPM tach. Other differences are that some do not have pins wired for all warning lights. That is easy to fix. Just get a spare power connector so you can transfer those in. I do also believe the later year models do not require the wire that goes to the battery feed to keep the trip meter set. This is nice because my trip meter has reset when I started the car with the battery a little low. The last difference is that on some, a cruise light is in one spot, where in others, it is a hazard lamp.

Here is a writeup for swapping the digital clusters into the analog S10's. Read up here for more specifics on the clusters so I don't have to retype it. :) This also tells you what you need to remove it.


When you go hunting, it will be best to bring a small 12 volt battery with you, like a UPS or motorcycle battery. Also bring some wires with clips. You are going to want to test the cluster when you remove it. These are famous for having power supplies go bad. Most have been replaced or resoldered. You can also get an upgraded replacement off Ebay pretty cheap. The first one I picked was dead and I replaced the power supply with a new one. The second one had already been fixed, which was a bonus.

After removing the cluster, you are going to want to get as much wire as you can that is behind the connector mounted to the dash. Cut it out and remove the connector. You will need to connect the pink wire in pin 15 and the orange wire in pin 21 to positive. Then connect the 2 black wires in pins 9 and 24 to negative. The dash should light up. Everything should be lit except for the idiot lights. As it powers up, MAKE SURE that all the bars on each bar gauge lights up as well as the digits on the speedo and odometer. If the orange and red lights on the tach don't light, no worries. It is just a bulb. Don't worry about testing the bulbs in the idiot lights. I didn't initially know which were ground and which were not, so I screwed up and fried a board. Just go find other GM cars from the era with clusters hanging out and snag a bunch of bulbs for yourself. You will need to fill in the empties if you want to use them and have spares for what might be burnt out. Once removed, your cluster and connector should look something like this:

Still more to grab while at the junk yard. That's covered in the next thread.
Last edited:
Other items you need to pick from the donor S10 will be the oil pressure sender and water temp sender with the pigtails attached. The water temp unit is at the front of the intake, while the oil pressure unit is all the way on the back of the block. It is on the top of the motor in the center. You can always just buy these new from the local parts store, but you will still need some plugs and wire. I also pulled the angle adapter off the S10 donor, although I don't think it is needed.


You will now need to go hunting for the VSS off a '89-'91 J Body (Cavalier, Skylark, Sunbird, Cutlass Calais. I bought a new one because there was no info about these before I figured it out. I pulled a ton out of cars in junk yards and gave up because I was misguided on which ones had what I needed. Anyway, it looks like the pic in the link below. Grab the wires from this as well.


The last part you will need to get this all to work is a dual output VSS buffer off of a '91-'92 Camaro with a 305 TBI engine. There are supposedly other cars with these, but I could never find the right combo. These years are guaranteed. The box is typically yellow, however the one I pulled is white and works perfect. The reason you need this is because it reads the AC signal from the sensor and sends a 2000 pulse per mile signal to the ECM for TCC lockup / cruise, and a 4000 pulse per mile signal for your new speedo.


That will be everything you need to get this going.
Dismantle of the TR dash:

So I don't have a good set up pics on the dismantling of the dash as I just went crazy one day, but here are the basics. If you need more details, just do what I did and search the other dash removal threads out there.
You will need to remove the radio and climate controls in order to get to the old VSS buffer and plug for the digital tach / boost gauges.
You will need to remove the bezel, lower dash covers, and the soft instrument surround.
You will also want to remove the 2 big nuts holding the steering column in from the bottom. This way you can lower the column a bit for easier access to get the cluster.
Remove the fasteners that hold in the cluster and pull it out a little. You will need to get behind it to remove the security light, check engine light, speedo cable, and the VSS sensor.
The bulb sockets just twist out. There is a tab to push on that will free the cable. It is tight in there, so maybe have someone tug on the cable from under the hood while you push on the tab.
The VSS is right next to the speedo drive. there is a tiny bolt (I think 7/32" but don't quote me on this) holding it in. Get a small socket and remove that.
Next, trace the wires from the tach / RPM gauges back over to the area between the cluster and radio area. I found mine just to the left of the climate controls.
Grab the VSS buffer and sensor assembly out of there as well. Note these connectors as you will need to tap into them.
At this point the old cluster should be free. You will also need to remove the plastic part behind it that holds in the bezel and has the DS vent. First, remove all the switches for the headlights and dimmer. Also remove the passenger mirror control if equipped. Once the switches are removed, push in the tabs to release them out the back. Same goes for the plug for the cluster.
Next. you will need to remove the small bolts that hold the plastic cover for the wiring harness loom to the back of the assembly.
You can also take out the speedometer cable as you will not be needing it anymore.
Once you do that, you will have the 2 parts below out of the car.


Here is what your dash will look like:

Alrighty then. Now that you have just royally jacked up the inside of your car and have all these junkyard parts laying around, it's time to get a hacking!

First thing is to start disassembling the digital cluster. Below is what you need. Make sure to save the colored filters that go over the gauges.

At this point it is best for you to start mocking things up. Lat the new cluster ontop of the old support and figure out what needs cutting. The object is to get the speedo close to center over the column and have this sit about 1/4" below the bezel.


Now you can see where to trim the digital cluster. Here is how mine came out, so I'm sure you can follow it. You will want to remove the gear selector piece and the buttons at this time if you have not already done so.

Now that you have the plastic around the bezel trimmed down, it is time to figure out placement and do some trimming to the cradle for all this. You only need to cut down the step on the right side, so reversing all this is doable. Once you trim so you can lay the cluster where you want it, pick 4 holes and drill the cradle. I used a variety of screws, washers, nuts, and thin aluminum sleeve to get the cluster placed. There are no exact measurements or science to this. I played around with it and shimmed / trimmed as needed until I got it right. See the pics below for reference:


Here is the cluster in place before I got it perfect. At that point I cut the screws to not protrude. I added a 5th mount point by drilling a hole in the tab at the top right of the pic above and adding a screw.


Next step is to clean up the cluster and put the filters back on. I used hot glue for this. Notice I trimmed the screws and also took apart the trip and E / M buttons so all I have is just the little buttons to push from underneath. It fits under the bezel this way. Eventually I will wire something to the switches, but it is not that important to me now.

The next steps are to make it all look pretty. In the very back of Home Depot, behind the window and door isles, I found that they have a sheet of tinted plexiglass. They also had black chipboard there, so this all was perfect for my project. Remember that the plastic cover on the cluster that was taken off was tinted. You will need to reproduce that or be blinded.

First was to make a cover out of the chipboard, so only the displays are seen. This makes it nice and clean. Use adhesive of your choice (double sided sticky tape or some type of glue) to attach once you are done. This was just the mock up. I had plenty of spare to make a second go and square everything up.


The next step is to use the chipboard as a template for what is needed for cutting the plexiglass. Attach that to the edges of the chipboard with adhesive.


Now put on the bezel and make sure it fits:


The next step is to finish cleaning up the bezel cuts. Use a dremel, sandpaper, file, etc.
VSS stuff:

This would be a good time to get the VSS items ready to go. Take out the whole speedo cable and then celebrate!!!

Remove the drive module and gear from the transmission. Note the orientation of the gear and tug it off or use a screwdriver to gently pry it off.


Next step is to put the gear onto the new VSS. If you got a used one, make sure to swap the gear unless they are the same color. Test fit the new VSS into the transmission. I found that even though they appear the same length, I found the sensor goes further into the trans, so I made a new notch about 1/4" further back that the one that is on it. Be careful as you will grind into the metal casing if you go too far. I also had to grind the tab that holds it in a little shorter. I have no pic of that, but here it is installed in the trans:


I used a connector that I found at the parts store. The original will be purple and yellow, which matches the VSS buffer. I believe on mine, I used purple to yellow and black to purple. Not sure if it matters as this is an AC pulse. You will need to run 2 wires to behind the dash, right about where the old VSS buffer connectors are. I followed the same path as the speedo cable and zip tied it into place.
Last edited:
Wiring stuff:

So my recommendation is to plan and take your time on all this. Figure out all the wire lengths to extend from the cluster to the endpoint and take good notes. Then mock it all up and label before installing it in the car.
Caspers Electronics has an adapter that you can plug into the OEM plug for the original cluster so you can keep things clean. I wanted to go this route, but forced myself into doing all this in about a week to get ready for a roadtrip and did not have a chance to buy it. I went the route of high quality wire taps. It was easy, I know I don't have to worry about a loose connector, and I still can remove them.
I will break all of this down the best I can.

VSS wiring:

Here is a diagram for the new VSS Buffer. Make sure you go by wire color as I've need a couple pics of diagrams with the wires in reverse order of the one I have. Those may be off a different vehicle though.


The 2 wire connector (purple and yellow) goes to the vss sensor that was installed.

Tap the + wire into the pink / blk wire on the 3 wire connector on the old vss buffer.
Tap the GND wire into the black wire on the 3 wire connector on the old vss buffer.
Tap the ECM wire into the brown wire on the 3 wire connector on the old vss buffer.
Tap the Cruise Control wire into the single wire on the 1 wire connector on the old vss buffer.
Connect the Speedometer wire to pin 11 on the new cluster harness (I'll cover that later).

MAP sensor wiring:

Since the cluster has been removed, it is now necessary to connect an alternate power source to the MAP. The best place for this is by the ECM.

Follow the wires from the boost / RPM connector behind the glovebox and over by the ECM. Find the grey wire in that harness and tap it into the grey / blk wire located in pin C14 on the ECM harness.

Now take the black wire from that and ground it. I actually think I grounded my MAP under the hood instead. Your call.

If you don't have a powerlogger or alkycontrol, then you still have the 2 bar MAP and don't need to do any of this because it is only going to the gauge you took out. I think it is best to wire it up now either way.

Here are some better instructions:


Cluster Connector:

I am to write this all up from the perspective of what wire on the new cluster connecter goes where on the old connector / car.

Below are some diagrams I went by. The first is the S10 cluster connector:


Here is the pinout for analog the TR's. Please note that it is not entirely accurate, so use this pic only for reference on pin # and orientation.

IP pinout.jpg

Now here is what I got from Caspers site. This tells exactly what is on all the cluster connectors:

More Prerequisites:

Ok, before wiring anything up here, you need to know that most of the bulbs use a ground signal, so if you connect something wrong, you could burn up a trace on the board.

Here is a list of bulbs that take ground signals to light:
Service Engine Soon
Running Lights
Check Fluids
Up Shift

Here are the lights that take positive signal:

If you are wiring up Alky Control and want to figure out what to use for the lights, you are in luck because they are both lit on the ground side.

Special note on security light:

If you have a security light that you want to light up when the car is off, then you have a couple options:
--The positive wires on the new cluster for the warning lights are supposed to go to an ignition source. The security light won't work if you wire it into something and the ignition is off. Now you could just wire the lamp positive wires to battery source, but if something else sends a ground signal while the car is off, it will light and the battery will drain. In my case, I used the low fuel signal in my Alky tank, which is ground, to the check fluids light. Since I knew wiring the "ignition 3" wires to batt would cause that to stay on, I opted to extend the wires on the security light and just pop its socket into the place for the upshift light.

Special note on Alternator light:

There is a generator lamp wire, however I don't see a lamp and also have no clue if it keeps your car charging. That's because I bypassed my lamp circuit a long time ago with a resistor when something got disconnected. You may have to do this too. I was going to post a link to the alternator field thread, but I can't find it.

So here is how I wired it all:


Sensor wiring:

Note about the coolant sensor:

Some of you will notice that the coolant temp sensor is the exact same one that is already on the top of the intake and feeds the ECM. I thought that I would have an easy kill on this one and tapped into the yellow wire off the sensor to the gauge. Make sure you don't do this. For some reason it screws with the signal and tells the ECM that the car is running at 1/2 the correct temp. I found this out the hard way when I could not start the car due to a "coolant temp too cold" code. Disconnecting it fixed it. I let the motor warm up and then reconnected it with Powerlogger connected. What happened is that even though the gauge reported correctly, the ECM showed 1/2.

So...just take this sensor and put it in the front of the intake where the temp warning light switch goes.

Connect the black wire to ground and the yellow wire to the temp sensor wire that you ran under the hood.

Oil pressure sensor:

This should go right in place of the stock sensor place. Update: You only need to run the tan wire in the middle of the plug to the gauge. The other two are for a switch that comes on when there is oil pressure. You could use this to trigger the fuel pump relay, so theoretically you would kill the fuel pump if oil pressure dropped completely.....but you would lose the prime feature and the car would take a long time to crank.

I think this covers all the wiring.

At this point, plug it in and make sure everything works before putting it back together.
Last edited:
At this point you are ready to tuck in all the wiring, finish off the bezel, and reinstall everything in reverse order.

Notes on fuel gauge:

So I'm not sure if it is because the tanks are different shapes or what, but the fuel level is not exactly linear on this. It does show empty right at empty and full when full, so the range is correct. Basically the level goes down slowly at first and accelerates as the tank gets lower. I justify it by knowing that the bars on the top of the gauge are larger. Here is the breakdown from full. I had accurate notes on all this, but misplaced it. I know what I have close is really close.

1 bar down = 13 gallons left
2 bars down = 10 gallons left
3 bars down = 8 gallons left
4 bars down (1/2 way mark) = 5 gallons left

1 bar below 1/2 = 4 gallons left
2 bars below 1/2 = 3 gallons left
4 bars below 1/2 = 2 gallons left
Last 2 bars lit and blinking = 1 gallon left
Empty = bone dry

Alrighty that should cover everything at this point. Enjoy and feel free to ask questions.
The way I read it...the Camaro VSS buffer is a dual output version, that produces a 2000 pulse / min. for TCC & Cruise AND a 4000 pulse /min. for the Speedo.
The way I read it...the Camaro VSS buffer is a dual output version, that produces a 2000 pulse / min. for TCC & Cruise AND a 4000 pulse /min. for the Speedo.

You are correct. The speedo needs 4000 ppm and everything else is 2000. That's why you need the dual output buffer....while that and the fact that the OE buffer is for an optical sensor.
The reason I am asking is because intellitronix has a GPS speed sensor that goes on the dash with 4000 pulses and my speedometer is way off.

So it's got to be the cluster having issues.

I got it out of a 91 s10 blazer
Hey Mike, I had one question.... where is the VSS buffer located on the Camaro? I have a S10 digital cluster, so I am really considering doing this until I can afford the new GNS gauge set up ( $1400 ). I think I will get another TR gauge bezel to cut on, buy the sensors new, and have a go at it. Thanks for this write up!! Gotta love GM interchangeability....
The buffer box on the Camaro and Firebirds is under the dash on the passenger side. Can get them from the '90 - '92 Camaro or Firebird with TBI. Along with the '86-'87 - '89 Firebird with TBI or the TPI setup.

Also used in the '87 - '91 (or so) Caprice. Been a while but IIRC, it is located more to the center of the underside of the dash.

The reason I am asking is because intellitronix has a GPS speed sensor that goes on the dash with 4000 pulses and my speedometer is way off.

So it's got to be the cluster having issues.

I got it out of a 91 s10 blazer

Sure you are not in metric mode showing Kmh? I can 100% verify these all need 4000 ppm I have 2 of them. One from a TBI and the other from a DFI. One is a '89 and the other is a '91. When I first bought them, I hooked them up to the factory wire that feeds the ECM and they were 1/2 the speed.