spare outputs

zguy360 · Post by **zguy360** » Tue Jan 03, 2006 3:23 pm

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-

zguy360 · Post by **zguy360** » Wed Jan 04, 2006 6:59 pm

Has no one hooked up the spare outputs for the Megasquirt II v3 with the new 2.33 firmware?

boost junkie · Post by **boost junkie** » Thu Jan 05, 2006 5:39 am

http://www.megasquirt.info/ms2/spare.htm

zguy360 · Post by **zguy360** » Mon Jan 09, 2006 7:22 am

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-

78Spit1500Fed · Post by **78Spit1500Fed** » Mon Jan 09, 2006 8:27 am

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

zguy360 · Post by **zguy360** » Mon Jan 09, 2006 8:53 am

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-

el-hardo · Post by **el-hardo** » Mon Jan 09, 2006 8:54 am

Hmmm, no idea, but i'm on this, too.
Do u test it with the stim, or in the car?

rb26dett · Post by **rb26dett** » Sun Jan 29, 2006 4:08 am

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.

rb26dett · Post by **rb26dett** » Sun Jan 29, 2006 4:13 am

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.

krisr · Post by **krisr** » Wed Feb 01, 2006 2:20 pm

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