Bronze MFP

Ok, the only troubleshooting i've done so far for this problem is swapping out the idiot gauge cluster and the a/c - heater logicon. the same symptoms exist no matter what combination of units i swap out. Here is the problem: the only thing that works on the AC logicon are the recirc. vent button and the fan speed control.
when I press the different vent control buttons (defrost, footwell only, all vents, etc) it lights up a different warning light on the idiot cluster.
if i slide the ac/heater control, it dims or brightens the lights in the idiot cluster. W.T.F.?
Is this related to the CPU at all or is there something else i need to re-solder?
I have to get this working this weekend. Since it started raining, i've gone through so many paper towels/cloth towels trying to keep the windshield defogged. its really annoying and a little dangerous.

OH91Convtguy

I have a 91 vert hope nothing like that happens to it I would freak out. Here is what MAZDATRIX has in there parts book about it. AIR MIX MOTOR-we have found more than a few of these bad. The symptoms are almost impossible to separate from a bad Logicon.Additionally-it is very possible to have the AIR MIX MOTOR, and the LOGICON,both bad. The factory manual gives a good meathod of testing these using a 12v supply and a volt/ohm meter. The motor controls the heater valve and the directing of the air under the dash, and replacement is not that complicated. Hope you get it figured out let us all know what it was when you do>PEACE.

Bronze MFP

*****, i was hoping it would just be a simple re-soldering, you know, something i can fix for free? I just dropped money to replace the starter that went bad on monday.
Second opinion anyone? mazdatrix already has enough of my money

Icemark

Not related the CPU at all.

The CPU controls the Horn, Turn Signals, High beams (on S5 verts), door open/key in or lights on warnings. Seat belt warnings, brakes lights (on S4 models) alternator failure warning (on S4 models), delay off interior lights, key hole lights.

From your description, you have bad air mix motor. I have posted how to test instructions many times as well as it can be found in the Factory Service Manuals (links for that can be found in the FAQ for FC sticky thread found at the top of this section). Note that a bad air mix motor will typically burn up the Logicon, and any new logicons that you plug into the bad one.

Bronze MFP

Thanks for confirming that icemark. Guess i'll be hunting down a new airmix motor this weekend. Hope i have an extra one in storage, but it seems like the things that break on my car are the extra parts I don't have.

thebigbluecan

It controls the brake light on the dummy light cluster? Is it supposed to turn on whenever you hit the brakes? Mine does and all the bulbs are working; and as I know of all cars with the brake light bulb light up when a bulb is out. is this true on rx7's?

Icemark

Yes the CPU controls the Stop idiot light as well as all three brake lights.

If you are getting the brake idiot light, lighting up, then you need to either release the hand brake, or put more brake fluid in the brake reservoir.

thebigbluecan

There is Brake fluid in the brake reservoir ( to the fill line) and its not the e-brake light .. The e-brake is down... It lights up whenever I press the brakes. What could it be? Its the light that says "STOP" that lights up.

Bronze MFP

thebigbluecan, check the connectors at the brake resivoir for the warning light and see if they are loose.

icemark, so far my logicon hasn't burned up. like i said, the blower control works, and the in cabin recirc. button work, everything else doesnt. at any rate i have an extra logicon or 2 around here somewhere.

thebigbluecan

Thanks Ill Check that later

Icemark

The driver circuits for each of those are different circuits.

There is a driver circuit for the Recirc, the air mix, the mode, and the blower (through an amp).

So when I say burned the logicon up, again, if you plug in a logicon to a bad motor it typically burns up the driver circuit for that motor, effectively damaging the Logicon so that it will never drive the air mix again, without replacing parts from the circuit boards of the logicon.

Bronze MFP

dang, well i must have burned all 3 up then swapping them out to check if one was the problem.

anyone have an airmix motor and a logicon for sale?

NZConvertible

That means a brake bulb is blown.

It's the BRAKE warning light that comes on when the handbrake is on or the brake fluid is low.