99 Miata ECU pinout and OBD2 port issues
 

Hi guys, and ladies


I didnt know where this should go, so if it needs to be moved go for it mods.


My check engine light came on the other day so I pulled out my handy scanner to see what was the issue. The scanner turned on but wasnt able to connect....weird.....


so I went to diagnosing.

I got my DVOM and checked the OBD2 port, the ground and 2 powers are working, leaving the issue to be with the signal (k) line.

I then checked what I thought was the correct pinout to see what line it is from the ecu to the obd2 port, and there was no pin in that position.


So either my signal wire has disappeared or I am looking at the wrong wire.

Help on this would be great, if you tell me to go MS3 then...well..i just might.


thanks!

When does your car hit the rev limiter, what rpm?

i havent hit it, but ive gone to 7k

Was the car modded in any way when you bought it? I'm thinking it might have the crystal mod, which ups the rev limit, but also makes the obdII reader not work.

hmm not that I know of, but its possible.

What is the rev limit supposed to be? And do you know what pin at the ecu goes to the obd2 port?

Rev limit should show up around 7200 on the tach, or 7000 in real life.

Miata Information

well ill go find out :p

lets say that it is the crystal, how does that disable your obd2 port?

Also thanks for that link, I just went through it though and I cannot find where the k line signal pin is at in the ecu plug. Mind helping me out?