W-body(?) pinout for 1227727?

[dyeager535]

The only versions I can find are very hard to read. Does anyone happen to have a better copy of say an '88 or '89?

Normally I'd just take the Y-body pinout and call it good, but (and I'll check if I can after work) it appears there is a wire already in the oil temperature location (C13 off the top of my head) which I don't think was used in any application BUT the Y-body. This ECM was already pulled from a car, but has 1989 3.1 Grand Prix on the tag. Was purchased from a wrecking yard, and they are small enough I think they labeled it correctly.

I know it's highly unlikely at best that all 1227727 pinouts were not the same, and the possibility exists that I read the connector numbers wrong. But the wire color in what I think is the same location doesn't match the Y-body, and enough other wire colors are different that I would like to verify what I'm looking at with the proper manual.

[EagleMark]

Like these?

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?391-1227727-1227730-ECM-Information-A1

[dyeager535]

That should work! I'll still have to compare wire color, but I suppose wire color is really meaningless. Then again, correct color makes diagnosis of problems later, easier, if I can match what I have up to a diagram.

This is the thread I found first: http://www.gearhead-efi.com/Fuel-Injection/showthread.php?332-1227727-ECM-information&p=2412&viewfull=1#post2412 Which is why I asked if there were clearer ones, I didn't expect there to be two versions of the same thing of different quality.

Found this one http://www.chevythunder.com/199091_corvette_1227727_ecm.htm which shows C14 as the oil temp input, and the non-Y-body diagrams here show nothing on that pin, so hopefully I just mis-read the pins.

Got a 2 wire CTS threaded for the oil pan, my tapping looks a little off, so we'll see if I can get it to seal. Interestingly, the first two wire I ruined was a *steel* body, the second one is brass. Then either figure how to get oil temp read in 6E, or wait until I convert to the 7727, which will be awhile.

[EagleMark]

Oil temp seems to be a Y body/Corvette thing. same with LT1 for 92 to 96

[dyeager535]

Right. I think there is already a wire in that position on the '727 I purchased, and this yard is so small I doubt they've ever had a Corvette in it, so I need to take the diagrams home with me, and see if I can't verify I'm reading the connector properly.

[RobertISaar]

the pin wiring will be mask specific. if you're running it on 8D, wire it as 8D, if running it on 6D/88/8F/A1, wire it as such. MOST of the pins are used for the same functions, but there are a few oddities that you can run across, such as EGR.

[dyeager535]

Ahh...I hadn't really run across that yet. Apparently if oil temp can be added elsewhere, it would make sense various masks could be pinned out differently.

No idea what mask I'll be running, probably from a 90-92 V8. 8D I guess.

[RobertISaar]

i could move around all of the temperature sensors so that none of them are on their original pins anymore, change about 5 bytes in the algorithm, and it will all still work correctly....

point being, there is some flexibility in where you can put stuff, but it's considerably easier just to match it to the factory locations using factory diagrams.

so grab yourself a 90-92 F-body or 90-91 Y-body LB9/L98 diagram and you'll be on the easiest path possible. probably need both, since IIRC, the F-bodies didn't use the oil temp sensor?

[dyeager535]

Yep, as far as I can tell, Y-body was the only one with oil temp. You didn't list '92 Y-body, something wrong with that year? I know typically later is better, only reason I ask.

Y-body diagram is the one I have, so rearranging pins should be easy. Now I'll have to figure out how de-pin those connectors. Didn't look at them closely, luckily I've got some pretty thin spring steel around, can probably make any "tool" I need to depin.

Not that it really matters, I've got to splice the '165 harness into it. So I'll need the '165 and wiring manual for the sensor side, and '727 for ECM side. :)

[RobertISaar]

7727 connectors are pretty simple to depin, just a little more effort than a 7730 style pin.

anyways: 92 corvette = LT5 or LT1, no L98.

[JeepsAndGuns]

C14, coolant level sensor. Going by what you have on your ecm, (coming from a 89 3.1L) it should be a factory $8F code mask. Pinout for that shows C14 as coolant level sensor. See here:
http://www.gearhead-efi.com/Fuel-Injection/showthread.php?390-1227727-1227730-ECM-Information-8F

(http://www.gearhead-efi.com/Fuel-Injection/showthread.php?390-1227727-1227730-ECM-Information-8F)Like robert said, pinouts can vary slightly based on code mask and what vehicle its being run in, and what engine its running. Follow the pinout for the code mask you plan on running. Ignore the wire colors since they will be different because of the same wire having different functions in different aplacations.

[dyeager535]

I'm going to have to re-verify tonight, was moving wires around last night and came across a few that can't be run in the 8D positions (cavity not molded for a pin), apparently that's why there are connectors of different colors.

Guess I'll be learning how to move things around within the code, eh?

[RobertISaar]

or....... you can do as i did and drill out the blocked positons and pull the wire through backwards and modify the terminal to fit through. i needed to do that for all of the extra circuits i opened up in my 16149396, uses the same connectors as a 7727.

trust me when i say that's about 100X easier than learning how to get the ECM to interpert the pins differently if you have no prior coding experience.

[EagleMark]

7727 V8 and V6 do have differant connectors, well connectors are same but some pins are missing. Been done before to use V6 ECM for V8 wiring and memcal.

[JeepsAndGuns]

What pins are you needing to use that you cant? I have a couple 7727's here and I plan on using one for my ecm swap into my jeep, and plan on running 8D. These came from like 90-92 cars ($A1) I went through and removed all the un needed wires and didnt find any that were not there that were supposed to be. I used the pinout I got here, I think it was for a 8D vette.
Mabey your older 7727 has different plugs?

[EagleMark]

There's 2 pictures of the plugs in this post. one is V8 and one is V6. This was pointed out to me years ago and pictures supplied by Dave W.

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?332-1227727-ECM-information&p=2407&viewfull=1#post2407

[RobertISaar]

there are actually quite a few different V6(W-body) versions of the plugs.... the 88 plugs are different from the 89-90, the 89-90 are different from the 91-94.....

there may or may not be subsets between those years as well....

[JeepsAndGuns]

Interesting, I did not know that.
The plugs on all 3 of the 7727's I have, have the plugs like in the first pic in the link mark posted. Colors blue, green, white, and orange.

[dyeager535]

The pin differences must have been why they made them different colors. I had wondered that as well, even the Corvette pinout chart references two different colors for at least one of the plugs, the same year.

The most important one I verified last night that is not setup for a terminal is the fuel pump relay pin (on the Corvette pinout).

I'm hesitant to try and modify the connector as A) the plugs seem to still be available pretty easily (especially from LT1 apps) so the time/effort may not be worth it and B) the cavity is cast larger than the nose of the terminal.

There are one or two more that can't be used that I will need, but I don't have my sheet in front of me. There are TONS of pins I won't be using (TCC, EAC/EAS solenoids whatever they are, likely EGR, etc), I think I came up with about 15 terminals that ARE drilled that I don't need to use, that the connectors are designed to use. So either the mask gets changed to use those pins for whatever I need, or I find the right plugs and use the 8D mask and the vette pinout. Just like using stock pinouts if possible so I can reference them at any time for diagnosis.

[JeepsAndGuns]

Do you go to the junkyard much? If so I would look for a early 90's car with a 7727. I have pulled one from a 92 grand prix, and another from something chevy, I think it was something like a lumina or beretta, cant remember. Just grab the connectors and some of the wire from one of those.
Looks like mark might even have some connectors with a 7727 in the for sale section. Never hurts to have a spare ecm.

[RobertISaar]

7727s ONLY came from.... 88-92 W-bodies with the 2.8/3.1(possibly the 2.5) and the 90-91 L98 corvettes.

luckily, about a billion 2.8/3.1 W-bodies were made in that period. :laugh:

and the connectors used were similar/identical to quite a few other applications as well, including 91-95 3.4 and 93-94 3.1(NOT 3100) W-bodies. IIRC, the LT5 and 92-93 LT1 PCM uses the same/similar connectors.

[EagleMark]

PM me an offer if you need it...

[dyeager535]

What happened to the best hijack ever? Cream cheese!!!

[EagleMark]

You saw it before I deleted the spammer... :rolleye: