I dont understand MS
 

i have a few quick questions about the ms1 for a 90-93
How do you make launch control work
is there only one wire out of the ms for ebc
and why is one of the sections labled TPS not connected to the factory wiring, its with the accessories?

*psshht* Calling Scott, we have a question on Isle Megasquirt please *psshht*

Hold on Changing Title

did i build the MS?

^pwned

i think,but its used. probably been through 3-4 people.

Confirmed that you did the original build.

I'd need to see the internals...specifically the underside of the board.

ok. let me open her up.

https://www.miataforumz.com/attachme...ine=1323648510
https://www.miataforumz.com/attachme...ine=1323648510

oldie but goodie.

launch should be set to js10.

correct about ebc. one wire, MS provides the PWM ground on the IAC1B output position. solenoid should be wired to a switched 12v source and the MS ground.

TPS stuff does not apply to a 90-93 that has no linear TPS.



came with a parallel harness?

i have a bmw linear tps, how do i use that with this setup. and it does have a parallel harness. so if i am correct ebc can connect to to the little blue caped connection on the car, and to the ms connection for ground.
did you build the harness, if so what wires am i looking for to do this the correct way.
https://www.miataforumz.com/attachme...ine=1323662060

forgot to mention that i want to wire launch control to a separate switch.

yes i built it.

do you have the center connector pigtail that fit into that middle plug? can you read any of the labeling? i only see knock on the one input.

the clutch input is the blu/wht wire that's opposite of the red wire coming off 1B. so position 1V.

EBC is one of the green wires on the middle connector.


tps goes back to that blue one, there should be a gray one labeled 5vref, is that on the harness?

i dont have the plug for the center. if needed i will go up to radioshack or something and get a molex connector for it.

there are 5 wires on the center in this order from left to right purple, space,pink,space,green,drk blue,space, drk green and white,

also forgot to ask about wideband input

The colors mean little, I need to know back to what pin they go back to the db37 connector.

But from what I can tell:

Purple was for a knocksenseMS input. JS10.

O2 goes to that pink wire.

Unsure on green.

solid blue should be the TPS input

green white unsure.


I'm also looking for a gray wire labled rvref, but I'm going to take an educated guess, and assuming solid green is 5vref and the green/white is the EBC out.

I can only confirm this when you tell me what pin they go back to the DB37 connector on.


It's probably easiest for you to just cut all those wires off the yellow connector at this point and run your own connections to them. Jus tmake they they can be disconnected without cutitng if you ever need to remove the harness. Its a shame you didnt get the pigtail with it.


So to run TPS, you'd need to extend the blue and green wires to the engine and hook it up to those properly, you can use the oem ground in the stock tps harness.

launch control you can cut off the harness and wire to your switch. I'd probably want the clutch switch AND momentary switch, so I'd splice the swtich into the blue/wht wire I pointed out, but leave it ocnnected to the actual clutch switch on the patch harness.

hey theres a thick grey wire connected to wiring harness but not the db37 ?

it better be... that's one of the CAS signals. That's not the one I'm tlaking baout and from teh pic it looks fine...but it should run back to the db37.

on the db37 green white is pin 31 green is 29, purple is 23,pink 24,

https://www.miataforumz.com/attachme...ine=1323793882
At the db37
https://www.miataforumz.com/attachme...ine=1323793882
it connects to the white wire, into the connector. it looks like the purple one is connected but its not.

scratch that above, the white wire runs through the center, didnt catch that till now

yeah you were off a pin too :)

everything is how i said before.

https://www.miataforumz.com/attachme...ine=1323816605

do you have a visual of what they go to? they are worn, and very difficult to read.

and 26 is green not gray

color isn't important, position is; sticking to everything i say in post #18.



https://www.miataforumz.com/attachme...ine=1323830784

wait why is the FP on the center connector. and whats pin 36

it's not. this is why i keep saying color is not important. Post #18 tell you what's on the center connector.

But I'll go back and restate it from left to right:

Purple, goes back to JS10, this is an input, it was used for knocksenseMS.

Pink, WBo2 input.

Green, 5vref this needs ot be wired back to your linear TPS.

Blue, TPS sig, this needs ot be wired back to your linear TPS.

green/wht, EBC out.


FP is pin 37, you have nothing on pin 37 because when i built that unit (cira 2007) we were just jumping the f/p relay in the diagnositics connector.

Will you be retaining the AFM?


Pin 36 drives on of your coils, and that's correct.

i wasnt paying attention to color i opened the harness up and the wire labbled fuel pump goes to the center. i was extremly confused. and no im going to the iat sensor. and i though you said js10 was luanch control.

and sorry im probably annoying the ---- out of you, im just trying to make sure i understand the best i can before i install.

JS11 is the launch pin, JS10 is going to be unused. I made error.

FP doesnt matter since AFM will still be attached. you're good to goz.

sorry for confusion, im not using afm, gm iat from diy autotune.

lol. then you'll need to do something for the fuel pump.

I'd run pin 37 to position 2O (i have to confirm this--speaking off my head), that runs back to the AFM connector, where you can jump 2O to the fuel pump relay ground at the connector.

so the MS grounds 2O, 2O is jumped at the aFM to the fpr, therefore the fpr turns on the pump. easiest way to do this. You'd want to remove this wire from the stock ECU, as im pretty sure it's a 5v output from the ecu otherwise. ground and 5v dont mix.

can you jump the fp and ground at the diagnostic box. or just make it switched underneath the dash

you can run pin 37 to the fuel pump relay under the steering column. tap into the lt green wire.

pin 37 at the db37 or somewhere else.

yes db37, which comes of the MS :)

there nothing connected to pin 37 on the db37. thats why i asked.

I mentioned that earlier. and you'll need to add one, and run it back to the fuel pump relay