Dakota Digital Speedometer calibrator

DieselDan

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Hey guys,
As some here may have been aware, I was having an issue with an incorrect speedometer after inadvertently installing a new transmission with an 8 tooth output gear on the tail shaft. This caused my speedometer to read roughly 10mph fast and there was no option for a speedometer gear that could fix it. So, I started looking into ways to rectify my problem.

A member here very kindly sent me a free Speed-cal, but ultimately it seemed to be defective, so I had to continue to find a solution. Because I'm a cheap a$$, I needed the cheapest solution available... The speed-cal is a tried and true solution to this, but it is a pita to setup the dip switches if you are using it in an oddball installation, like I was.

I came across the Dakota Digital SGI-5, it does the job of modifying your speedometer output to make your speedo read correctly. It can be used for a vast range of applications. Most people, I would assume could use it to correct their speedo after changing wheel/tire combos.

http://www.summitracing.com/parts/dak-sgi-5 - Cheapest I have found. There are a few sellers on eBay for a out $5 less after shipping, but I preferred to deal with a reputable seller.


I found this article on TCCOA about where someone had a bit of trouble getting it setup, but ultimately got it working correctly. He actually used it for the same issue I had, installing a later model transmission...
http://forums.tccoa.com/showthread.php?p=1364032

The SGI-5 requires switched accessory power, ground, and the speedometer input. Essentially, 3 wires. Now, because I like wiring, and a factory look, I didn't want to make a big mess of the harness and go cutting things, I repinned the harness under the dash going down to the transmission.

Connector 213 is under the EATC control and is the last connector before it goes through the floor, under the car.
Pin 9 : red - Switched accessory power
Pin 8 : dark green / white - speedometer signal
Pin 4 : pink / orange - speedometer ground

The red wire is a switched accessory power wire and splits off to 3 power wires that go into the valve body on the transmission. The dark green/white wire is the speedometer signal out and needs to go into the box and then out, back into the car's harness. And lastly, the pink/orange wire is the signal ground for the VSS but I also used it as a ground for my SGI-5. It is ground 200 and is mounted to the structure of the dash board.

Using some old ford connector harnesses and connectors, I was able to hook up the SGI without cutting any of the car's harness. I pulled the pins out of connector 213 and put them into a connector shell by themselves, and then hooked my newly made harness inline. All of the wires were a splice (power/ground) but the green/white circuit had the SGI installed in line.

Setting the 4 dip switches to the down position is what is needed in our application, along with using output 1 as your VSS signal out. (There are 3 other outputs for different applications.)

Here are some pictures of what I came up with...
1BD75535-8BEA-4DF4-A310-84F0011D296B-2552-00000116F6931EC0_zpsbd22d08b.jpg


17E91762-D2F7-4B24-B810-C3D1C53B54E2-2552-00000116ADF08D3B_zps5c919b37.jpg


594B6998-54BB-4DA8-A8E4-953EBD18B67B-2552-00000116B90AAAAB_zps9f5e8802.jpg


FC85C651-A463-4472-B020-EE4922FD79DC-2552-00000116C2C38747_zpse21cbfc9.jpg


The wires you see in the back of that connector are my power/ground/signal.
EDBEF5D4-6DB3-4A69-BE74-83B3ED4E3BEF-2552-00000116DD6AB6D6_zps316fff7e.jpg


I will add the connector face pictures and whatnot this afternoon.

Anyway, I plugged in all of my connections and fired up the car. Because my speedometer was already "close" I did not have to adjust the "course" adjustment, just the fine adjustment. Calibration is a BREEZE! I set my phone on the dash with a speedometer app and took it for a spin. When you start to move, the green LED on the module will flash, to tell you that it is receiving a signal. On the main road I set my cruise to 55. My speedometer said about 66. Now, I just started pressing the Down button to lower my speedometer's speed. Slowly, by using the up/down buttons on the module, my speedometer began reading the vehicle speed perfectly! That's it, once it's dialed in, you are done!

My module was sitting just under my EATC where I could hold it while driving. This afternoon, I will secure the box under the dash. It was a breeze, the hardest(time consuming) part was wiring it up and figuring what pins to use for what I needed. (But now I've done that for you!). Once I made my harness, it took only about 5 minutes to hook it up to the car.

I am extremely satisfied with the SGI-5 and would highly recommend it to anyone in the future! It is also about $40 cheaper than a speed-cal and was far easier to setup.

I will add more to this thread later, but for now, you get the idea!
 
I have one of these as well, since I have 4.10 gears, and I am going to the trans shop this evening to help instal it. Your thread is super helpful Dan! Can you post more pics? I am excited to get this done on my car. I was fearing it the most. I am going to have to look for some spare wiring plugs so I can do the same thing.
 
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You can do all of the wiring under the dash. Remove the center console and your EATC. There is a black plug there, about an inch above the carpet to the left. Here is a pic: (The circled connector is the one you need. The red Arrow shows where the harness goes through the floor.)
0876bca3-7b75-4e3e-8235-7ffffc00f380_zps30e80601.jpg

This picture shows again the red circled connector is the one you are repinning, and the blue circle shows the connector I used to integrate my harness into the vehicle harness.
EEA289C4-2456-4DE5-B88E-3F195877DC6A-2552-0000014DB997D632_zpsa3146553.jpg


If you remove the EATC, you can get to that connector a lot easier. You are only concerned about the connector that you can unplug and pull out. DO NOT mess with the connector that is mounted to the dash. While looking at the connector face, you need to remove pins 4, 8, and 9. See my diagram below. It includes a connector face picture.
VSSWiring_zps8037e7fb.jpg


My installation is very clean and 'factory' looking. You don't have to get this in depth, but I chose to not cut/chop any of my harness. If I ever wished to, I could repin the harness and go back to original.

You are splicing power into the Red Wire, pin 9.
You are splicing ground into the Pink/Orange wire, pin 4.
You are putting the SGI-5 In-Line with Dark Green/White wire, Pin 8.

I hope this helps!

FYI, this is what I used. You can get these connectors and pins from assorted places on Ford vehicles from the Junk Yard. I have a box of assorted wires/pins/connectors. So that's what I used.
9EDC5C71-3CAD-4A92-9EEA-41DBDF64C45E-2552-0000014FF51881D3_zpsdd146df4.jpg

4774548F-7AC0-432F-80ED-A29F20A990B9-2552-0000014FF9A1C28B_zps0ea9644d.jpg
 
You could make money off these Dan! I would buy one right now for the ease of it lol!
 
I'm mildly confused still, you used new plugs, is there a reason you didn't use the factory harness plugs that were in the car already?

Not enough pins in originals?

Plus you show a gray plug in your recent pics? Where's that one?

Sorry for the dumb questions.
 
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1742FDC3-844F-4E6C-A5CB-63D5CB9CE044-3507-00000191DC7AB46F_zpsc016bb59.jpg


I really hope this clears this up, I'm tired of making pictures. ;)

The picture of the wires lying on my desk and the gray/black connector shells were taken after I installed everything. The gray shell is identical to the black one I used, just different in color.
 

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