I've had my T56 and SGI5 alib box for a few months now, and the speedo works just fine, no strange jumps or wiggles like some other guys seem to have. But I can't get the CC to work. I have a 91 TPI, so if anyone who has the SGI5 and got their CC to work could let me know where they attached the wries from the ECM to the SGI5, I would appreciate the help. Or is it that the V6 CC box doesn't work with the L98 ECM? Thanks for any help!

BTW, the CC did work before the V6 swap!

 

works for me. plugged in the SGI-5 between the VSS and the ECM.

 

Yell yeah, that's the only place to put it. What I ment was, what wire in what SGI port?

 

viperwsu, how is your box hooked up now. Im just curious. I took my CC out

 

NIIIIIIIIIICE paint job! Mine sucks, but then I live in a college town where I get a door ding a month. I'm not shelling out cash for paint until I get out of here.


The sgi box is hooked up thus:
I screwed it to the top of the tranny tunnel next to the hole where the auto shifter cable used to go, so the wires run from the tranny, through the hole, and to the box - only about 6"; there isn't any interfence that I have seen. They go to input and ground.

I have the "high" ecm input going to app 3 (I think - I'll have to check next time I take off the shifter plate). I had the "low" ecm wire hanging loose, but CC didn't work. I tried it on ground, and CC doens't work. I am thinking about trying it on app 3 as well, but I'm hesitant to try new things when I don't have a backup ecm. I've fried an ecm on the V6, and don't want to do it again!

Of course I have power and ground too. Power is tapped into the stereo's constant power feed, and ground is just ground.

 

If your speedo is working it's not your SGI-5 configuration, it's something else. What, I have no idea. The only practical words of advice are to get a wiring diagram for the ECM and make sure you have everything hooked up properly. I needed to do absolutely nothing to get my CC working. All I did was plug in the SGI-5 and the ECM takes it from there.

FWIW, I'm using out3 from my SGI-5. Low ECM cable feeds the SGI-5 ground. Low VSS cable ties to the low ECM cable. I ran twisted pairs to the SGI-5. ECM wires (2 wires twisted) up to SGI-5. VSS wires (2 wires twisted) up to SGI-5. ECM low to ground port. ECM high to out 3. VSS low to ground port VSS high to signal-in.

 

what the heck are you talking about? Help me out here on this. How do you know what side of the plug is high and low. I think the VSS wires on my car are yellow and purple. I cut the connector off them and grounded the purple wire and put the yellow wire into the OUT 3. I then took the plug connector on the T56 and gounded one of the 2 white wires. I took the other one and put it into SIG IN. I also grounded the box itself and got 12 volts for it from the fuse block. Does this sound right? Im asking because my speedo goes crazy when I come to a stop at a light. Once I take off, it reads fine. The only wires I twisted are the yellow and purple wires off the orignal VSS connector.

 

I used the purple wire for ground. I didn't use a chassis ground. According to the Helm manual, the purple is ground, so that's what I used. So, I ran purple to the SGI-5 ground terminal (no other ground leads), then I ran VSS-B to the SGI-5 ground terminal. Yellow goes to Out3 and VSS-A goes to Sig-In. For power, I ran it off the radio's switched power accessory lead. The fusebox should be fine, but I didn't want a constant power draw with the accessories off.

 

You know, I was talking to Chris B about his 91 w/ T56 and he mentioned there being a 2k output from the ECM??? I dont' have a Helms for a 90-92; does this ring a bell for you guys w/ a svc. manual? Sheer guesswork, but for a few reasons I was thinking that was the wire going to cruise...
Matthew

 

It's 4K according to the service manual and I believe that to be 100% accurate. However...the SGI-5 documentation might be sketchy. I couldn't use the 4000ppm SGI-5 output (out4). I tried out 3,4, and 5 and I think out 3 worked for me. Others may have had other experiences. out3 is the 8000ppm output according to the SGI-5 doc for App#3, but it's the 4000ppm AC output for App#2...

 

Okay with the cruise being 4k (I may have been remembering wrong) and the speedo being 4k, is it feasible to tap into the speedo signal that comes from the ECM? Seems like the easiest option if your speedo is working.

Then again, this may be a "back to the basics" problem with the cruise.

-Matthew

 

What do you mean by VSS-B and A? Take a look at how how I have mine setup in the previous post, does that seems like it is the same as yours. For my grounds, I put a short jumper wire in the GND terminal on the box and twisted the other 2 ground wires fom the VSS plug and ECM wires and grounded all them together to the chassis.

Why are we havig these stupid problems with these things?

 

When I put in my T-56, I got a VSS pigtail from GMPD, and both wires were white. The VSS for the T-56 (mine is from a '97 Camaro) just opens and closes the connection between the two wires - or in real terms, it shorts it, creating a digital sine wave. Since the VSS is really nothing but a rapid on/off switch, it doesn't matter which wire is ground and which is sig-in. If it was still connected to the ECM it would matter, since the ECM provieds the ground. But with the SGI-5, we pick the ground. Thus, I would assume that what 91Z ment by A and B was just a shorthand way to say input and gnd.



Also, as I sit here at 11:30pm, trying to picture everyone's configuration, I realize that I have never once seen someone's config. So, I grab the handy digital camera and a torx driver, run outside, and here is my config:

 

The SGI5 is mounted on my tranny tunnel, inside the center console, and under the front edge of my stereo.

pwr is the red wire, tapped into my stereo

gnd is ecm-low(ppl) twised with a spliced gnd (note the blue crimp on the black wire). This twist was ment to be temp, so it's ugly

vss ground goes to the blue splice, along with a short jumper wire that grounds under one of the shift boot screws.

out3 goes to the yellow wire, which is ecm-high

sig-in is vss power (other white wire)

None of my wires are twisted, and my speedo doesn't jump around, so I doubt I am getting interference. Maybe it's because I have the sig-in and pwr wires on opposite sides, maybe it's because the vss wires are only about 6" long. Who knows. Don't ask what the DIPs are set at, it will change with tire size, rear gears, etc.

 

If I remember my wiring diagram correctly, the purple and yellow wires are supposed to by alternating current at 4k, and the ECM takes that signal to output 4k and 2k digital signals. The 4k goes to the speedo, and the 2k to CC. So I don't think that you can tap the CC into the speedo like that. What really messes me up is figuring out how the ECM still runs the speedo when I didn't have the ecm low (negative part of the ac sine wave) connected at all. I just recently put it into the gnd port, and I didn't get any difference - although a few days later my distrib ignition module blew. Coincidence?

 

i too can not get the cc to work, without the sgi5 hooked up(fatory) the cc will work but once i get it put on and dialed in it will not turn on. i never hooked it up like u guys but i got it to work for me pretty easy, speedo is right on the money but cc will not work. any ideas or has any one had liek with the cc workin?

 

viperwsu said it right, but being a stickler for details, all I did was follow the original wires back to the tranny, and then looked at the new pigtail. The housing has an A and B written on it. The old VSS connector also had an A and B written on it. That's pretty standard for a connector, so you know which wire you are talking about regardless of wire colors.

It mattered for me, because I don't use a chassis ground signal for the SGI-5. I have it wired so I can splice it in if it's necessary, but it wasn't. The only thing supplying ground to the SGI-5 is the purple wire.

viperwsu,

For ****s and giggles, did you hook up the brake switch for the cruise control? Other than that, I honestly don't know. I don't know much about the CC box and it's interaction with the 730 ECM. I've not had problems, so I haven't delved into that part of the service manual. You don't sound like you have a problem with the SGI-5, just something between the CC and the ECM.

 

I haven't messed with the CC switches on the brake pedal, other than moving it from the auto to manual pedel bracket. I haven't been able to locate a store with that stinking clutch pedal CC release switch yet . . . although I haven't been looking too hard lately. I wouldn't think that would make a difference, but then on our cars, who knows what can change things.

I've debated putting the wole car up on jacks, popping the hood, and "driving" it up to 35mph, and see if the servo tries to engage, but I'm a little nervous about having the tires spinning that fast while on jacks. Any opinions here?