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spare outputs

Posted: Tue Jan 03, 2006 3:23 pm
by zguy360
I feel like a fine fellow having to ask this question, but I am having a hard time trying to figure out the spare outputs that became available with the new firmware. I am wanting to trigger a relay for water injection and a shift light. Looking at the spare output documentation, it looks like the IAC pins would work great for this, since they can supply enough current to trigger a relay. From what I gathered, you change the setting for the IAC control to being on, but set everything to zero so it doesn't change. I have done this and am not getting anything out of any of the IAC pins. Is there something that needs jumpered inside of the megasquirt, or something that needed to be done differently when it was built? Any help would be greatly appriciated. Thanks!
-jeremy-

Posted: Wed Jan 04, 2006 6:59 pm
by zguy360
Has no one hooked up the spare outputs for the Megasquirt II v3 with the new 2.33 firmware?

Posted: Thu Jan 05, 2006 5:39 am
by boost junkie

Posted: Mon Jan 09, 2006 7:22 am
by zguy360
Thanks a ton, but if I hadn't already read all that, I wouldn't be posting questions. I have followed all the instructions on that page but am still having problems. I would like to use the IAC outputs since they can directly control a relay. I am not getting any voltage output from any of the IAC wires when I try and set up the spare outputs. Any ideas why this isnt' working?
-jeremy-

Posted: Mon Jan 09, 2006 8:27 am
by 78Spit1500Fed
Did you install the +12v jumper from the PCB to the MSII daughtercard?

Are you measuring between the two leads, or between one lead and ground? (i.e. CoilA+ and CoilA- or CoilA+ and GND)

-Brian

Posted: Mon Jan 09, 2006 8:53 am
by zguy360
No, I didn't install that jumper. Now that you mention it though, it jumps right out of the text at me. So I should just be able to install the jumper and go from there. Can I use just the one power wire and not the ground wire? It would be easier to chassis ground the other side of the relay. Thanks.
-jeremy-

Posted: Mon Jan 09, 2006 8:54 am
by el-hardo
Hmmm, no idea, but i'm on this, too.
Do u test it with the stim, or in the car?

Posted: Sun Jan 29, 2006 4:08 am
by rb26dett
i was wondering the same thing about which two of the four to use, and grounding, but upon re-reading the spare.htm page, it appears that it doesnt matter which from each pair you choose, just that one will be inverted. so on might be off. grounding outside should be fine.
So, by picking 2 of the 4 IAC outputs
correct me if i'm wrong...

fred.

Posted: Sun Jan 29, 2006 4:13 am
by rb26dett
on reflection, gounding outside needs to be done, if one were to use the pair, when it switched off, it wouldnt, it would just reverse the polarity.

once again, correct me if i'm wrong...

fred.

Posted: Wed Feb 01, 2006 2:20 pm
by krisr
zguy360 wrote:Has no one hooked up the spare outputs for the Megasquirt II v3 with the new 2.33 firmware?
I use the FIDLE for my electric fan relays (switches negative on 2 relays) and the Knock Enable port (jumpered to SPR3 from memory on the DB37) to give 5V to my HEI 7pin module when RPM > 350.

I'll be using an IAC stepper so I can't tell you how those spare ports work. I have had no issues to date with either FIDLE or Knock ports in my configuration.

Hope that helps
Kris