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-   MEGAsquirt (https://www.miataturbo.net/megasquirt-18/)
-   -   Tapping Into Injector Harness for CAS (https://www.miataturbo.net/megasquirt-18/tapping-into-injector-harness-cas-8205/)

cjernigan 03-15-2007 01:28 AM

Injector Harness & Ign Coil Outputs
 
For my '99 I have a CAS from a '97 and from this schematic
http://users.forthnet.gr/ath/twikicore/extwir2.jpg
via Reverant I noticed that the CAS connects to the injector harness. Being a '99 this is not stock wiring for me. Where would be the best place to tap into for this connection when installing the CAS?

akaryrye 03-15-2007 02:13 AM

so you are going to use it to trigger megasquirt right? I believe there are 3 wires needed: Power (12v I think), Ground, and the output signal. As long as you use a common ground, you could run any 12v source to it and run the signal wire back to the megasquirt.

Edit, just looked at that schematic, its different from others I have seen. Anyway, it looks like the CAS has 4 wires actually, because there is a CMP and CKP signal. Both of those wires would need to be run back to the megasquirt.

cjernigan 03-15-2007 02:17 AM

K i'll look into that then.
Could you reference me in the general direction of some other schematics that you speak of. Thanks

akaryrye 03-15-2007 03:16 AM

http://www.madracki.com/miata/wiring.html

That site has been very helpful to me. Its really not as complex as it seems, just follow the wiring back to the source. At first when you look at diagrams, it can be confusing, but it makes sense after a bit of studying. For a CAS, you only need it to trigger an RPM signal for the megasquirt and that will be its sole function. When you realize how all those wires work, you will see that it is just a few sensors to determine what the engine is doing (CAS, Temp, Etc) and a few output signals which tell the coils, injectors, etc what to do and when based on what the sensors are telling the ECU.

Reverant 03-15-2007 06:14 AM


Originally Posted by cjernigan (Post 92661)
For my '99 I have a CAS from a '97 and from this schematic
http://users.forthnet.gr/ath/twikicore/extwir2.jpg
via Reverant I noticed that the CAS connects to the injector harness.

It's not the injector harness, it's a +12V supply (see how it comes from the main relay?). Get a +12V from the MS board, you need this one to have power while the car is cranking or it will not start!

ALSO, I have certain spark mods done a bit differently (as well as a knock sensor circuit and 3 stage shift lights, so please don't take this diagram as-is, you may burn stuff!

Jim

cjernigan 03-15-2007 03:27 PM


Originally Posted by Reverant (Post 92688)
It's not the injector harness, it's a +12V supply (see how it comes from the main relay?). Get a +12V from the MS board, you need this one to have power while the car is cranking or it will not start!

ALSO, I have certain spark mods done a bit differently (as well as a knock sensor circuit and 3 stage shift lights, so please don't take this diagram as-is, you may burn stuff!

Jim

Yeah I see how it is connected to the main relay for 12+V thanks for clearing up that confusion. So your spark mods are different I'm having trouble finding good pinout numbers for the coil outputs then. Your's are 3 & 36. Kags are 27 & 29. I'll be running the internal MAP sensor so there are no complications there.
http://users.forthnet.gr/ath/twikicore/extwir2.jpg

Kags Pinouts
20 - Air Intake Temp (ECU 2P) (red-green)
21 - Coolant Temp (ECU 2Q ) (Blue-White)
22 - Throttle Position sensor (ECU 1N) (Red)
23 - 02 Sensor (ECU 2N) (Red-Blue)
24 - RPM Signal (ECU 2E) (white)
25 - 1A RPM Signal (ECU 2I) (Black-White)
26 - TPS signal 5vref (ECU 2L) (Lt Green – White)
27 - 1B Coil (ECU 1G) (Brown-yellow)
28 - Power 12V (ECU 1B) (White – Red)
29 - 2A Coil (ECU H) (Brown)
30 - Idle Air Control (ECU 2W)
31 - Not used
32 - 33 - Tied together Injectors (ECU 2U) (Yellow)
34 - 35 - Tied together Injectors (ECU 2V) (Yellow – Black)
36 - Not Used - This ignition is not used in my setup (see 27 / 29)
37 - Not Used - I am wiring the FP to come on when the ignition is on at Diag port

Need help with this one, not sure which to use.

cjernigan 03-15-2007 05:09 PM

As per DIYautotunes tech article. Sorry guys, being dumb again.


The Primary tach input (CKP) (Reported to be White on Miatas) is connected to pin 24 on the MegaSquirt's DB37

The Secondary tach input (CMP) (Reported to be Yellow on Miatas) is connected to pin 25 on the MegaSquirt's DB37

When wiring up your ECU later: Spark Output A will come out on pin36, and Spark Output B will come out on pin31.

Reverant 03-15-2007 05:21 PM

I don't currently remember which pins I used for the spark output on the DB37 connector because I have too many mods (CAS, external MAP sensor, second baro MAP, EGT, launch control, switchable tables) forcing me to take a bit different route than what the diyautotune article said.

Jim

Ben 03-15-2007 05:32 PM

your fancy ass megasquirt runs batch injection? :confused:
:gay:
Oh, sorry, it's now
:pitlab:

richyvrlimited 03-15-2007 06:30 PM


Originally Posted by Ben (Post 92914)
your fancy ass megasquirt runs batch injection? :confused:
:gay:
Oh, sorry, it's now
:pitlab:

wtf? the early stock car runs batch? Sequential is an improvement, but it's hardly the be all ....

Ben 03-15-2007 06:47 PM

look at the wiring diagram posted. it shows batch injection, but I don't know what it's from.

Yes, the 1.6 cars are batch injection.

Reverant 03-16-2007 04:20 AM


Originally Posted by Ben (Post 92914)
your fancy ass megasquirt runs batch injection? :confused:
:gay:
Oh, sorry, it's now
:pitlab:

Yes, can you tell the difference between sequential and batch?

Jim

richyvrlimited 03-16-2007 02:11 PM


Originally Posted by Ben (Post 92942)
look at the wiring diagram posted. it shows batch injection, but I don't know what it's from.

Yes, the 1.6 cars are batch injection.

what it's from? its the outputs from the Megasquirt with MSnSE. that's why they're Batch as that's all it can do.

why the hate?

Al Hounos 03-16-2007 03:13 PM

he's jealous.

Ben 03-16-2007 03:41 PM

just an observation.

you MS guys are sensitive like teenage girls. :gay:

cjernigan 03-16-2007 03:49 PM

I have an overly large clit.



(Clerks 2- The Movie)

slimeball6969 03-19-2007 12:31 AM


Originally Posted by Ben (Post 93264)
just an observation.

you MS guys are sensitive like teenage girls. :gay:

its beyond your comprehension, stick with your overpriced named brand, while i still smoke you in my ms powered cars :nono:


it may show batch, but everyone and their mother wire it semi-sequential 1-4/2-3

richyvrlimited 03-19-2007 03:39 PM


Originally Posted by Ben (Post 93264)
just an observation.

you MS guys are sensitive like teenage girls. :gay:

but you're observing something we're already well aware of, the MS runs batch Injection. Then you precede that with gay smilies.

Who's the immature teenager?

magnamx-5 03-19-2007 04:15 PM


Originally Posted by richyvrlimited (Post 94143)
but you're observing something we're already well aware of, the MS runs batch Injection. Then you precede that with gay smilies.

Who's the immature teenager?

ME :sadwavey:

Ben 03-19-2007 04:30 PM

Jeezus, not just sensitive, but also sandy 'ginas! I made an observation. I was surprised--that's all.

I welcome to meet any of you MS guys on or off the track.


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