Note:I just wrote this and haven't spell checked it, plus I have a broken collar bone, so if there are mistakes, please be kind as typing is extremely dificult
If your reading this your probably just like I was when I started my Megasquirt (refered to from this point on as MS) venture, Intrigued and scared. I knew enough about cars and ECUS and stuff but when it came to standalone, I was pretty much in the dark. Don't worry, I'll try and make this painless as possible. Alot of people want to hookup a megasquirt, but are intimidated by the wiring, if you follow this guide, you should be able to do it. I have faith in you. By the end of this writeup you should have made this:
What this guide will hopefully help you with is hooking up a MSv3 ECU to your Stock Bluetop wiring harness, WITHOUT TVIS control, TVIS control requires a extra circuit to be built, and that you'll have to get into on your own, i'll provide a few links at the bottom to give that info though! You will also be able to use the toyotas sensors and VAST gnition system in a seamless and easily swappable manner, so if (for whatever reason) you can hookup your stock stuff and still have it run in a matter of minutes. I'm going to try and keep it dumbed down as much as possible, because the problems that I found when hooking mine up was information overload. so lets go
heres your standard disclamer: YES YOU CAN BREAK STUFF AND SERIOUSY MESS UP YOUR CAR, SO BE CAREFUL, STUPID! THIS WIRING WILL NOT WORK FOR A MSv2 ECU BUT CAN BE USED AS A GUIDE. THE TACH SIGNAL WIRES ARE DIFFERENT! THIS GUIDE WORKED FOR MY APPLICATION BUT I CAN'T GUARANTEE IT WILL WORK FOR ALL SETUPS! I ASSUME NO RESPONSIBILTY FOR ANYTHING THAT MAY COME OF THIS WRITEUP INCLUDING DEATH, EXPLOSIONS AND THE DOWNFALL OF WESTERN CIVILIZATION.
with that out of the way lets begin, here is a list of parts you will need to complete this
- Wire - 16-18g wire, colors helps troubleshoot down the road, I went to princess auto and grabbed ever color they had in 18g, you can use just one color if you wish though.. it will just make your life kinda interesting.
- Solder - Rosin core is the best,
- Soldering iron - I had a 35 watt iron from princess auto.. worked great
- wire strippers - or a knife or something like that
- Shrink tube - you don't need much,
- 85-87 GTS ECU - You'll need the ECU connector
- Male DB37 connector - if you bought a complete MSv3 kit it should have came with one
- MSv3 ECU - preferably loaded with MSnS-Extra and associated board mods
- Vaccum line - Rubber black stuff to run from the Throttle body
- GM AIT - Part #'s as follows: GM #25036751, Standard AX1, GP SORENSEN 779-19001, AC DELCO 213-190, NIEHOFF IGNITION TS83631 (was DR-136W), WELLS SU107, MSD 2320 (includes connector), Wells PN 235, NAPA PN ECHTSC300, Niehoff PN PS77421, Conductite/Dorman PN 85110. Make sure youspecify you need the connecting pigtail as well.
- Laptop - with you version of megatune installed
- DB9 cable- for connecting MS to lappy
- Patience
- Time
- Cold beer
Step #1 Dissassembly of your factory ECU
Remove all the case screws and pull out the "brains" of your factory ECU (the printed PCB) we need to remove the yellowish connector from the end that plugs your ECU into the factory harness, yes that means you have to unsolder ALL those pins (TIP: snip the leads off the board close to the PCB, you only need to solder a small piece of wire to the ends) ANNND if yor ECU has all the pins Labled, don't ruin the pinout labels, that will help you immensely to make the harness. I have heard that not all are labeled though, so you may get lucky. If not you will need a pinout of the factory ECU, There is a link in step #2 showing the bluetop pinoutsOnce you have the harness off the board, set the board aside, if it's labeled, keep it handy cause you will need it! at this point you should have something that looks similar to:
http://pitobread.com/doristuff/p3080001.jpg - huge pic warning
Straighten all the pins out, clean them with a solvent like rubbing alchohol or something. If you have got this far you should have a unconnected ECU connector with a bunch of straight and clean pins on the back. if some are pretty magled, don't worry, you only need about half of them to make it work
Step #2 Soldering madness
Ok heres where it gets fun, below you will see my chart, if you have the pinouts printed on the PCB, it will now make sense to you what goes where at this point, if you look closely at your DB37 (on either side) you should see tiny numbers labeling what pins are what #, take your time, solder and check to make sure things are going to the right spot, and check again once soldered, you'll do fine. I reccomend "tinning" your leads when soldering to make your life easy ("tinning" is soldering both pieces before connecting them to get adequate solder on both) make sure your iron has been on for 5-10 min and that it is nice and hot, this is also where the shrink tubing comes into play, put the tubing on the ECU connector side of the harness, on the leads you solder, just for added security. there is no need of it for the DB37 end as the connector is covered with a casing. also when stripping your leads, dont expose too much wire, you only need about 5-10mm of wire to solder to the pins, this will help keep the wires from shorting out on each other.
A - means that no wires are connected to that pin on either side
http://www.pitobread.com/doristuff/bluetop_pins.jpg - Link to ECU pinout WARNING huge pic
MSPin = ECUpin as seen on the PCB = Color I used
37 = vc = Red
36 = igt = White
35 = #10 = Brown
34 = -
33 = #20 = Green
32 = -
31 = s/th = Red
30 = -
29 = -
28 = +b1 = Yellow
27 = -
26 = vcc = Red
25 = -
24 = ne = Blue
23 = ox = Blue
22 = vta = Yellow
21 = thw = Green
20 = tha = White
19 = -
18 = -
17 = -
16 = -
15 = -
14 = -
13 = -
12 = -
11 = e02 = Black
10 = e1 = Black
9 = e2 = Black
8 = e01 = Black
7 = -
6 = -
5 = -
4 = -
3 = -
2 = -
1 = -
Once you have this done, give a light tug on all the wires, make sure they are securely connected, a loose wire could mean headache intermittent problems... so now is the time to check everything. Thats it. Check, double check, triple check all your wires. I pulled all the extra pins out of my ECU to try and keep stuff from shorting out and have it alot cleaner back there, if you've got this far, you should be on your way. wrap everything up and put the cover on the DB37.
Step #3 AFM shennanagans
Now before you get all gung ho and hook this up, there is one other issue you have to attend, pop the hood you will need to either T off or using a unused vac line, run a vaccum line in to the MS ECU's onboard map, try and find a body plug and stick it through there, as I did. put it through the rubber part so the metal doesent cut through it and leave you with problems onces thats connected move over to the AFM, remove the connector, and unbolt it out of the car. If you look at the connector that the harness plugs to you'll see 4 screws, unscrew it, we need the connector to make a harness for the AIT and fuel control so once you have it pulled off te AFM body, cut/unsolder the wires, now we need to:
Jumper pin 2 to pin 5 with a piece of wire, solder it in place on the AFM connector
Connect AIT wire to pin 7 and solder it in place on the AFM connector
Connect AIT Ground to pin 3 and Solder it in place on the AFM connector
Tape it up
Plug it back into the AFM connector on the Harness
Here is a pic of what i'm referring to
Now you can go ahead and hook up your AIT and put it into your intake somehow(drill/tap a hole and thread it in) it can be close by for the time being but it should be in the intake path.
Thats it.. you did it big guy, sit back and have a beer
Originally Posted by neil85ae86
