DIYPNP 1994 No spark, No RPM signal.
 

Hey guys,

I recently built a diypnp v1.5b for my miata, with the intention of boosting it. The car is currently NA, and I'm trying to get it running on megasquirt before I turbo it.

I built the board with the offical DIYPNP guide, and then performed every cross connection, pull up, and configuration from this writeup:
DIYPNP MegaSquirt installation for the Mazda Miata
Everything works on tunerstudio, I have intake temp, coolant temp, and fuel, but the ignition circuit appears to be entirely absent. I have checked every connection having to do with the rpm and ignition signals, including testing from the microsquirt pins to the output pins of the converter board itself, and everything checks out perfectly. However, there is no rpm displayed while cranking, except for it changes to 1rpm from 0rpm when I begin cranking. I'm really pulling my hair out on this one, I've tried every single thing suggested in every forum post related to this issue, with no change whatsoever. Any help with this would be appreciated.

I should add that the car still runs perfectly using the stock ECU.

what didnt you do correctly?

If I knew that I wouldn't be posting

You had to have built it wrong, or you've been bit by the "loading a 3.3+ MS3 firmware on a 3.2 MS2 basemap" glitch that may not exist that I don't care enough to try and replicate.

DIYautotune's website has nice pictures showing what the board looks like populated, I suggest you compare side by side like those old newspaper "spot the difference" games...

Is there a way to manually test the cam angle sensor circuit? I feel like my problem lies somewhere in there.

I literally just told you, visually compare it. If you don't get a rpm signal cranking, it's fucking toast in settings or hardware.

No need to get feisty- I posted that reply before yours showed up.

I'm doing a visual inspection ASAP

Checked the board, nothing looks wrong. I feel like it's a software thing.

Which firmware did you load?

Compare these settings to yours, they may be in different places if you loaded a MS3-esque firmware.

https://www.miataturbo.net/attachmen...ine=1438381597

Stuff I underlined may be different. Don't use those numbers.

I am using the ms2/extra 2.10. It's old, I used it because it was the firmware quoted in the crossover guide that I used.

My ignition settings window looks different than yours, and I'm not sure what the red highlighting means, but everything else looks alright.

would you recommend I use a later firmware?

https://www.miataturbo.net/attachmen...ine=1438382289

If you don't see any indication of crank or cam signals from the composite logger then you built the DIYPNP wrong in some way or another. I don't see loading a newer firmware helping. Jumper configuration does not change via firmware, but I have a hunch loading old tunes on new firmware has the potential to scramble some renamed settings.

Tunerstudio layouts change by firmware, I don't know what the red bars mean but I bet it's because those are pretty critical settings, not error checking or anything like that.

Flashed a new firmware and took a log of cranking, not sure exactly what I am looking at but it looks like I have input from the CAS.https://www.miataturbo.net/attachmen...ine=1438386991

you're not getting a cam signal.

why did you load such an old ass firmware?

use 3.4.0.



you either did the jumper wrong or forgot the pullup.


pics of assembly.

Here's some pics of my assembly. I left out the radiator fan and A/C pullups, but those should not be crucial to getting a spark. I've also got mixed information on weather or not I have to jump the ignition pins near the top of the board.
https://www.miataturbo.net/attachmen...ine=1438448654


https://www.miataturbo.net/attachmen...ine=1438448654


https://www.miataturbo.net/attachmen...ine=1438448654

What ended up being the issue???

Was there ever a resolution to this? I’m battling the same issue. ‘99 with a diypnp no cam signal.

Not the OP, but I had a very similar sounding issue with my diypnp (96 though). What ended up being the issue was some extreme feedback from my iacv. I installed a flyback diode across the leads on my iacv and bam everything fired right up.

if you haven’t give that a shot I highly recommend it. You should have a spare diode in your kit. If not, pm me. I bought 100 off amazon and I’ll send you.

Wow, I never would have guessed that being the reason for the missing cam signal. I didn't build this diypnp so I don't have any extra diodes laying around. I'll take you up on that offer to send me one. Thanks for the help!

Check block to chassis and the harness grounds, too.