I did it last night and no change, at all! I'm pretty frustrated at this point since i cut and soldered all the lines, it wont be neat and clean and easy to do it again, maybe I got something backwards but I don't think so.
Hey North, are you sure you cut the blue and yellow wire that is from the lower wire connector or the top bundle? the top bundle connects to the fan switch mechanism, the one you should be cutting is the connector that is below that bundle. It has fairly smaller wires to it. You can see it in the picture given by the follow-to. Its the lower white and black connection.
I'm torn on what to do with this...Mine has been getting just a little worse year after year for 11 years...As it finally warmed up in my area...I no longer have speeds 2 or 3...but 1 and 4 still work fine...2 has been problematic since i bought the car new...3 would 'usually' work, but occasionally flicker if the interior of the car was blazing hot...after 5 minutes or so of speed 4, 3 would then work without a problem...not the case any longer...
I did it last night and no change, at all! I'm pretty frustrated at this point since i cut and soldered all the lines, it wont be neat and clean and easy to do it again, maybe I got something backwards but I don't think so.
There really is no danger of any kind of short within the connector itself,... if they do touch each other, the fan just turns on. The fat black wire should never touch ground though because that is B+ from the battery and you will blow a fuse.
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So my question is: I know this overall is caused by the PCB for the hvac system, right? I know there is an additional issue caused by corrosion of the fan speed switch, but i've checked mine numerous times and it still seems ok...clean and tight...
If i source a revised PCB...what am i getting? does this control board include a new harness and adapter? As in, does the full unit replace the harness that i'd be hacking in to? Or do i utilize my existing wiring to simply snap into a revised circuit board? Depending on how that works out, i'll probably try this first...and if i mess it up just go source a new board with included wiring...if it doesn't include a replacement wiring lead and connector, i'll probably just find the pcb entirely...
crossover sells the revised unit straight from mazda...its not cheap, but is the exact part number required in the official Mazda TSB about this issue...I may be able to find one locally, but its been a while since i've dug around under my stereo...other than just unclipping the speed switch to see how its doing...
That plastic connector itself isn't very important. You could remove the individual terminals from the plastic holder,... clean them all up,... replace the terminal end on the fat black wire (trimming an inch or so off the end of the wire) and just plug them onto their respective terminals on the back of the switch.
There really is no danger of any kind of short within the connector itself,... if they do touch each other, the fan just turns on. The fat black wire should never touch ground though because that is B+ from the battery and you will blow a fuse.
That's not true, the fat black wire is ground. The color should give you a hint
It's caused by a combination of a bad control circuit, corrosion inside the switch, and corrosion on the contacts. Like PCB said, there's a good chance that this method will fix the problem for you. Worst-case, you can always remove it. It's not a very invasive process.
This is the first I hear of a TSB for this problem, got a link to more info? I'm curious