Like several others on this board, I'm having trouble getting my Dakota Digital SGI-5 speedometer interface to work after I swapped out my T5 for a T56...I'm not getting my speedo to register at all when I'm driving the car. You can see below how I wired it...sortof, anyway...I had to use a lot of red wires 'cause that was all I had . Here's the rundown:

PWR: Tapped into power wire from stereo...accidentally used the switched power, though...still gotta change over to constant power...would that prevent it from working? I wouldn't think so, since it is on when the engine is running...let me know, though

GND: Combined three wires together...(1) wire run to screw on tranny tunnel for ground, (2) purple wire to ECM, and (3) one of the wires coming from the VSS on the T56 (it doesn't matter which one, does it?)

Sig-In: The other wire coming from the VSS on the T56 (once again, does it matter which one you use?)

OUT4: Yellow wire to ECM (I may end up changing to a different OUT depending on the output I get once this thing finally starts to work...I have a 1228746 ECM on what was originally a 305 TBI)

Can any of you tell where I'm making a mistake? I have verified that I have a good ground and power using a test light (when the ignition is on, anyway). Any help will be MUCH appreciated...thanks

 

Here's how I have mine:

SGI-5 box:
Power for box: Accessory circuit of car
Ground for box: Chassis
Speed signal in: Fed from 4th gen VSS (see below for details)
Output from box: Output 3

Car's harness:
Black wire: to ECM (not changed) from Output 3 of box
Pink with black stripe wire: Not connected to anything

4th gen VSS harness:
One wire: To speed signal in of box
Other wire: To ground terminal of box (recommeded by Dakota to minimize interference but could be grounded to chassis theoretically).
Does not matter which wire goes where as the sensor is an AC signal generator.

I think you need to unground that purple wire from the ECM... And your output needs to be changed.... The black wire on mine is yellow if you trace it through to the ECM and the pink with black stripe is the purple one.... Not sure why they didn't carry the colors of the wires all the way to the VSS.

I also had to make a change in the PROM regarding running a magnetic VSS to make it work, but mine has a 730 ECM...

HTH

 

I'll try ungrounding the purple wire tomorrow and see if that solves the problem...man, I hope that's all it is. You know, Dakota Digital sure could give clearer wiring instructions than they provide with the box.

By the way, what change did you make on your chip for the VSS? Did you have to adjust some of the bit flags or something?

 

you need out put #3, then see what your readings are. after tons of time I figured out my "SGI-5A " was really a misslabled "SGI-5" and required a differant set of instructions. the out puts are the same just the switch settings are differant


mine would only read on out put#3. 4,5 wont work unless you remove the buffer box (which I ended up doing because of all my problems and I am very sure I did not need to remove it)

 

I'll try OUT3 this weekend and see if I get anything...were you able to get a correct speed with OUT3? The SGI-5 manual says that OUT3 is an 8000ppm output, compared to the 2000ppm output that it states a TBI computer requires...although I've read posts by several people that had to use a different output.

As for the DRAC, or buffer box, where on earth did you find it? I actually attempted to trace it down once, but gave up after I lost the purple and yellow wires in the dash.

 

Pay no attention to what the manual says. For some reason it is off. I have the sgi-5, but I would assume it's about the same on the outputs. I had to use OUT3. You are correct in that it doesn't matter which wire you use as a ground coming from the vss, just remember it is important to spiral the ground wire and signal wire, otherwise the signal will get messed up. I didn't do a very good job doing it, and my speedo loves to jump around when I'm at a dead stop.

 

the buffer box should be mounted on the same braket as the ecm. it may have been moved but, should be close by. there are ways to slow down the reading if it is too fast or even way to fast just let us know what you are reading.

 

Just thought I'd provide an update here...much thanks to r90camarors for the sound advice. I switched over to OUT3 (despite the instructions that came with the box) and it works just fine! Now, all I have to do is adjust the dip switch settings because the speed is reading a little low. THANKS!!! :hail:

 

hey i am wondering what matt87gta did to his chip ont he 730 ecm reguarding the magnetic vss. did you enable it or dissable it? i have mine disabbled right now with the same wiring you have you box set to and i get nothing from my speedo on application 3 output 3. any ideas please respond.

 

hey guys i got my speedo to work now finally. bad ground going to box. wierd huh? anyway new problem. i was using application 3 with output 3 and i cant get my speedo low enough, the adjustments iont he sgi dont allow me to adjust any lower. i have tried now every application and every output and still that same. output 4 doesnt work alkong with out put 2. output one is way to high and out 3 comes the closest but still progressivly off. meanign when i am driving 10 my speedo says 15 but when i am going 30 the speedo says 45. can anyone help me here. i am very perterbed with this problem. i have 3.27 stock rear gears for my 87 gta i have no idea what gear is on the tranny vss but i thought that shouldn't matter anyway just listing incase it does. please get back to me asap so i can fix this thing. letme know what output your using and what application. switch one and two settings would be nice.

 

As long as you are still within the adjustment range (i.e. not at the minimum multiplier in the table), you probably just need to power off the box in order for it to accept the latest dip switch settings. That is exactly the problem that I encountered because I have my box hooked up to constant power...in hindsight, I should have hooked it up to the ignition power, but oh well. Just pull the negative cable off your battery and hook it back up...I'll bet your problem will be solved. Dakota Digital says nothing about this little "requirement" in their literature...I had to call them a couple of times before they finally fessed up about it.

 

ok i got the power of to store the settings thing but what is the min multipler your talking about. which application are you using. i was trying to use app 4 with out 3 and with the beginning settings it has in the book and my speedo reads like 110 at 20 mph. which is like a ratio of .18181 or so and that isn't in the book. so what do i do? this is with dip switch 2 off so i would be looking under cal. low correct?

Nate

 

I had to break out my Dakota Digital manual, but it looks like the minimum multiplier is 0.251 (look at the bottom right corner of the table). In other words, you are using too high of an output because you need a 0.181 multiplier.

I have a TBI, so I'm not sure as to exactly which "application" you should use, but I DO know that their manual told me to use app 3, OUT5...but I ended up using app 3, OUT3. IOW, DD doesn't have a clue as to what works properly on our cars. The DRAC on a TPI car may be different, but I'd guess that you should use either OUT4 or OUT5 on application 3 in order to get your speed within the controllable range of the dip switches (0.251 - 4.000 multipliers). As a reference, my speed was reading within 20 mph of my actual speed with the beginning settings once I finally started using the right output.

Just be sure to remember to power down your box in between dip switch changes...

 

ok thanx for the info i wanted to know if it would matter if i have my power connected up to the acc power also. does it need constant power?? i wouldn't see why unless it has to remeber settings which it shouldn't. but let me know if i have to swicth this over to constant power or if i can leave it on the acc power. thank you for your help

Nate

 

Like I said before, I think it's better to use accessory power because the box will automatically reset every time you turn the ignition off. It won't lose any settings when it powers down because you physically flip the dip switches to program it.

 

the box doesnt remember or forget anything. the only adjustments are the switches.

it SHOULD be on switched power.. and only be on when the key is on. otherwise it will drain your battery.


below is the wiring for the SGI box.. even though you have it.


heres a link to the 2nd page of my T56 install answers thread
it also mentions SGI box stuff including calibrating:

https://www.thirdgen.org/techbb2/sho...0&pagenumber=2

that should help ya out.

and yea, the instructions that come with the SGI box are wrong

 

and yea, the instructions that come with the SGI box are wrong


thats because there are two instructions (sgi-5 A, sgi-5) was wrong on mine. the sent me the other instructions to try and it worked

 

i got mine to work. i knwo it is at least accurate at 30 mph (that is what i calibrated it at) it seems to be very accurate at all other speedo to though. i wired mine like in the above picture. you do have to shut off the box to reset it with a new config (weird since it has dip swicthes and you shouldn't have to) also my config is opposite any config in the book mine isn't even listed!!! i have number one off and number 2 on then alternating of and on from number 3 to number 9 and 10 is off to give a 0.374 ratio...

thanx for all the help!!! it has been 2 years since my speedo has been accurate (my 5 speed had the wrong vss gear when i installed it 2 years ago)

 

hey i wanted to add just for anyone else looking at this topic that even though i twisted the wires comming out of the t-56 vss very tightly that when i am not moving the speedo may jump and when i rev the engine it may jump also. sometimes when my subs are on it will jump.. it is rock sloid when i am moving though.

 

mine did this too.. drove me nuts.

its "noise" in the electrical system... if you get a "noise filter" from radio shack (its ment for stereo systems) and wire it in the +12v line before the SGI box, it stopps doing it.

 

thanx for the info. now this noise filter any specific one i need. like what are the specs i am looking for when i go to pick it up. i dont want to get one that isn't rated for the right amount of amps or something like that. basically i am asking what part number or model number did you buy and install that worked??

 

id have to pull my center console panels out, and stereo out too see the filters numbers.. i have it mounted behind it...

its not anything special.. teh SGI5 box draws almost no power.. its a simple solid state device... any of them should work...

if i recall mine was just a black or gray plastic blob with a wire come out each end.. it looks kinda like a battery with gray shrink wrapped plastic around it.


it looks very similar to the one at the top of this search: http://www.radioshack.com/search.asp...p=search&SRC=1

im 90% sure thats the same one, from looking at it.. in anycase, reading about it tells me it should work.

 

I got the new and improved SGI-5B installed last night and boy that was a chore. I wired it like the directions say, but low & behold they were wrong. I just looked at what each swich (mine only has 4 dips and 2 push buttons) does and what the outputs are and went from there. I wired the pink/black stripe wire in the harness to the ground as well. I finally got a signal and my speedo doesn't say 154mph when I'm going like 10 anymore. Tonight I have to fine tune it, but the 6-speed is finally almost done. All I need now is an alignment to finish it off...don't ask.

 

Alright now damnit, am I too stupid to get this thing adjusted right or what? I goit it all in, and the speedo working, but I can't even really get it close to being right. At approx 85 (that is what my butt says) it reads like 55. Anyone have any tricks to share about the SGI-5B before I get on the horn with Dakota Digital?

 

no tricks, but i have a question...


what the heck is a 5B? is it a new model? it has buttons on it?



going off previous Dakota Digital products, id assume their method for calibrating is accurate... even if their wiring diagrams arnt.

 

Yes the SGI-5B is the "new & improved" box. It has 4 dip switches and 2 push buttons (1 up & 1 down) for adjustment. I am just having a helluva time getting it to read fast enough. I'll call them to see what they have to say, go home figure it out and post how to work it out. I was just hoping that someone on here had already dealt with and fixed this problem. Oh well. If you never lead the pack, the view never changes!

 

hey guys i wanted to know if i have to buy thisnoise filter or if i could just wire in a capacitor. i remember something about caps being noise filters from electronics class... am i wrong or what if not what kind of a cap and how big should i use.. i really dont feel like paying the 19 dollars for the huge 10 amp noise filter when the buffer box only use probably .5 amps or less to run.

Nate

 

Well this is going to have to wait just a bit longer. It seems that the throwout bearing decided to go out so the car is not real driveable at the moment. I have a whole new clutch on the way and should be back in business this weekend, should be...

 

Do we have closure on the SGI-5B issue yet? I'm having the same problem.

 

I have a SIMPLE question before I attempt to try my SGI-5 A.

You guys are complaining about the instructions, whats wrong with them???!!!

All I did was switch from 2.72 gears to 3.73s and now my speedometer reads about 77mph when a car pacing me is going 70. I have a 2 wire plug in the transmission, 86 tpi 305 automatic.

I figure I would follow APPLICATION 1 or 2 in the instructions because the SETUP TIPS on the first page say "if your speedometer reads but is just off you probably need application 1 or 2"

Am I going to run into any problems if I follow the wireing diagram and beginning switch settings?

I dont want to be stuck for hours if the instructions are bad and the settings should be different for my car.

Thanks

 

they tell you to use the wrong output.
if you use the wrong one the speedo doesnt work.

 

I have yet to solve this problem yet, but it's tough to solve the problem when you don't try... I've had a couple other things come up (my wife's car is broken) and down (namely every drop of water in the Northern Hemisphere has fallen on my town in the last few weeks). I really don't like driving the car up here when it rains like that because the roads around me have ruts that hold about 3 inches of water. It's like driving a boat and I don't want to be looking at the speedo, and get hooked by a rut and go in the ditch. I WILL absolutely get it addressed this weekend, provided that we get the Grand Am fixed first. I'll let you know what it takes as soon as I figure it out.

 

want my best guess?

theres probly multiple outputs... they all run off diffrent multipliers.

you're at max adjustment on one output... if you put it in another output, you should be able to adjust it in.....

 

Wrong, tried it. The output I've got it in is the only one that would even give me a speedo at all. I think that I have the "Output Speed" dip in the wrong position. I think it needs to be in high speed output, and then I can turn it down from there. I really don't think that it's going to be too tough, once I get the time to fix it. I'll let you know for sure though when it's done.

 

I followed the instructions for the sgi-5a application 1 and it works perfect. It took me 1 & 1/2 hours to do it start to finish with the test drive. The instructions were correct for my application. I guess im lucky I didnt run into problems like you guys OH, and the BEST place to hook it up for a power source is the black plastic accesory box located underneath the kick panel to the left of the fuse box. It has a lot of orange wires going into it for things like power windows and power seats, locks, and other key on power acessories, there are extra slots built in for add ons.

 

The SGI 5 and 5 A look identical, is that wiring diagram the same for both? I have a 5 and want to install it soon.

 

I'm also having the problem with the speedo jumping around when at a stop. It works great when driving though.

It says in their instructions that you don't want to have the tach & speedo wires too close together OR when the signal in & out wires are too close.

So putting a filter on the power input will help? It always helps to have a clean signal. More input from everybody out there who's solved this problem???

 

You can read above that people have had to do at least one of the following to fix "jumpy" speedos :

1) Twist the VSS input wires together
2) Install a noise filter inline with your 12V power supply

 

There are also a few other options to help fix the "jumpy speedo" at idle. I had this issue for about a year rewiring it several times. Twisting the input cables did no good for me, i even switched to grounded shielded cable to no demise. I talked to electricians at work added a capacitor on the power line to eliminate spikes (helped but did not eliminate) I even sent the box back to Dakota Digital and they sent me a new one and it did the same thing...After talking with tech support....they had me wire up a voltage regulator to put on the power line, from then on NO ISSUES WHAT SO EVER. Something they said the jeep owners have had to do in the past with noise in the power lines that would mess up the output signal. I do not have the diagram here at work, I will have to look for it when I go home to see if I still have it....

 

I tried wiring it in like the diagram shows today but ran into a problem. Where are the connectors to the ECM/Speedo? I couldn't find them anywhere.

 

If you're running a T5 tranny, the Vehicle Speed Sensor (VSS) connection is the connector located toward the back of your transmission. Check out this thread for pics...it's connector #2 on the T5 pic:

https://www.thirdgen.org/forums/tran...?highlight=T56

I'm guessing the connector would be in the same area on a 700R4...dunno for sure, though.

 

I found the VSS wires, and had everything hooked up except for one thing, ad that is the wire that goes "out" from the digital box. I just couldn't find those connectors that the OUT3 is supposed to run to. I've heard you can get a PCM burned that can solve the speedometer issue too, maybe I'll look into that.

 

I know the thread is old, but for reference points, on my 91 TA this is what I did swapping from a T5 to a T56 using the SGI-5A.

Power is obvious. Use a chassis ground and one of the wires from the VSS to go to the ground terminal. The other wire from the VSS goes to the input. The Purple wire from the chassis harness is not used and the Pink wire goes to the OUT3. Dip switches are as follows.

On|Off|Off|On|Off|On|On|On|On|On

My speedo was reading 100mph at 40mph before.

This PDF helps alot:
http://www.dakotadigital.com/pdf/sgi-5a.pdf

 

Is this box used between the trans and the wiring that use.to be pluged into the original vss or between the computer and speedo in the cluster?

 

Man, it's been a while, but pretty sure it goes between the VSS and the wiring loom