Where did you pull your switched 12v, constant 12v and ground from?

I am running the switched 12v and ground off the same source as Megasquirt and my 12V constant from a 12v source from the old stereo wiring.

The problem I am having is when the meter is displaying an afr of 12.5 the signal MS is seeing says 13.5, a little too far off for my liking. Also MS is set up for AEM linear.

 

I'm likely going to wire it like I did last time, with a relay off of a switched power fuse, cruise control sounds good, to a distro block and fuses to do all the switched power for gauges. And then the couple that need constant power will get it fed straight to the gauge fuse block from a constant power fuse.

 

So did you have a uego, did you wire the switched off the cruise control, and what constant power source did you use?

 

That was how I wire any gauge with those wiring requirements. I do not know if the cruise is switched power for miata's and I'll need to look in the fuse box to figure out the best constant source to use. Last time I wired in gauges the relay also powered my intercooler pump (air/water) so I pulled directly off the main terminal under the hood with an inline fuse. But you dont need that much current for just a wideband.

 

I just used the stereo wiring since it was closest, although I'll be rewiring it to the power/ground on my DIYPNP once I get off my ***. No issues regarding TS/gauge being different.

There's only a power and a ground, did they change the wiring? There should only be four wires - power, ground, afr voltage output, afr serial output IIRC

 

I picked up the analog meter uego back in April and it calls for a switched 12V and a constant 12V (along with 2 signal wires, a dimmer input, and ground).

 

I did mine exactly as leafy did, wired it to the DIYPNP through the DB9 connector

 

So the db9 was your switch and all the power came directly from the battery? What did you source for the ground?

 

Everything went through the db9. It is powered and grounded from inside the MS

 

does that eliminate/reduce the variance between the AEM and the MS?
if not, what did you do to bring the two into agreement?
and is the agreement over the entire range?

 

I did nothing to calibrate it. The gauge read spot on to what it showed in Tunerstudio so I didnt mess with it.

 

Did you switch from volts to afr/scale your afr table?

 

Did you? That could be why they are reading different. I had to switch mine over upon initial startup. I wired mine through the MS as well.

 

I did not although after I made this thread I noticed Joe's thread on doing so.

 

Ive got my harness ready to be plugged in but not sure where to put each of the colors. This is what Im thinking so far but please throw in your two cents.
Ive got red 12v about to go to blue cable coming from ignition in my NA
black will go to a good ground source
blue is serial (will this even be needed for me?)
white 0-5V output (I know this has to go to my megasquirt pnp somehow but Im not sure how) I keep seeing videos of people seemingly splicing this into a one wired sensor in the engine bay but its not communicated well...
Pictures/links to other sources is always appreciated

 

MegaSquirtPNP by DIYAutoTune.com
Pin 21, assuming an MSPNP2. What is your ECU?

Alternative is into the socket for the factory narrowband O2 sensor plug in the engine bay, I will be wiring my haltech into this in the next couple of days but i cannot confirm which pin it is, I will be fishing it out with the multimeter.