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F100 CPU#2 repair

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Door buzzer sounds if the key is in ign off position on both doors
I have managed to induce several different "buzzer/beep/chime" sounds today! Can you confirm if it is an "interrupted" buzzer sound on a door open condition, not continuous?

Some further testing today, so:

"....with ignition on, under what circumstances can chimes be induced?" - could this happen if the boot and/or hood are ajar? If not, what else might induce it?
 
Beep beep when door is open. (Checked my video on my thread)

Nothing when the hatch is open unless mine isn't reporting it back as open or the hood but i don't see any sensor/switch to say if that's open
 
Some serious work went into producing this F100 pinout function list today.

I have learned a lot about the F100 circuit functions by changing input conditions and probing with a multimeter and an oscilloscope. The only failure mechanism that would prevent a repair would be failure of the 4 bit microprocessor, which is custom mask-programmed at manufacture to Mazda's design and no spare parts are therefore available. All other components look to be replaceable.

It would also be possible to replace the whole module with a new design, using modern components and a programmable controller.

Although I claim "100%" confidence for the function of some of the pins in the attached, without actually checking on a real car (rather than my bench simulation), I can't really be 100% ;)

I'd welcome anyone checking the described functions on, so I can be 100% on all the pins, enabling me to progress, with confidence, to designing/building a bench test box.
 

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Beep beep when door is open. (Checked my video on my thread)

Nothing when the hatch is open unless mine isn't reporting it back as open or the hood but i don't see any sensor/switch to say if that's open
Thanks - that is EXACTLY the beep sequence I'm getting (y)

Re the hatch/hood, the only way to know for sure would be to trace the F100 "1K" pin to wherever it goes. Something in the car should produce a battery condition on that pin (which could be a hatch light switch, when open) and, when the ignition is on, will create a chiming sound from the F100 module "sounder".
 
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