1991 Vert w/airbag...
It would beep 5 times, over and over again, when started and the Hi-Beams didn't work.
I did a little searching and found that the two together usually signify a bad CPU, rather than a misaligned steering wheel.
Per usual, Icemark had the answer.
I replaced the CPU with one from Mazdatrix and now it does not beep, the "hey your seatbelt isn't fastened" warning chime works, (or maybe it's the "your door is open and the key is in the ignition" warning chime; whichever, it didn't work before) the ignition light works, and I'm guessing that if I check the Driver's door key slot, that light works now too.
Long story short...This is an 89-92 Horn CPU w/Airbag
This is the replacement I purchased: http://www.mazdatrix.com/86-92Electrical-Chassis.htm Part # 67-5640-FC66
First PM with an Address gets it for free (as in beer).
Aloha,
~j

 

I have had the same problems, and have been contemplating how i would go about fixing it and where to start.

your symptoms were identical to mine, and i now know what to fix.

thanks for the confirmation.

 

Is that the first CPU board you have purchased? Good Luck and I hope it lasts well.

I however, fixed mine permanently-

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/s5-dimmer-fix-840197/

 

Yeah, my first replacement.
I dig your fix, if mine goes out again, I might try it. Thanks.
Aloha,
~j

 

That new board will last for a good long time.