Solution To Flickering Fan Speed 2 Or 3 A/C PART 2

I tried this both ways. First i cleaned and crinmped the connectors. Didnt do anything. Then I soldered them. Nothing.

I dont see how this is supposed to fix it anyways. My fan blower has and still works fine on all speeds. Which is exactly what its supposed to do. The only thing that happens is the A/C turning off in speeds 2 & 3. I don't see how doing this to the fan speed switch matters. Because when thew a/c is off the fan still blows in all speeds, with the a/c on it blows in all speeds.

I'm just gonna get the wiring diagram and wire the a/c switch directly to turn on the compressor when i want it on. Its stupid to have it tied to the damn speeds anyways. Besides i already did that mod a while back that stopped the a/c from coming on automatically with the defrost.

I will probably have it still be tied to the 0 speed so its off when the fans not blowing though.
 
I wanted to report back a few weeks after I did this fix. I have recently had to use the A/C alot due to rain and humid weather, and it has been fantastic. It hasn't flickered since I fixed it, and my A/C stays constantly on rather than it engaging on and off.
 
I wanted to report back a few weeks after I did this fix. I have recently had to use the A/C alot due to rain and humid weather, and it has been fantastic. It hasn't flickered since I fixed it, and my A/C stays constantly on rather than it engaging on and off.

AWESOME!
There's nothing better than the satisfaction of fixing something yourself instead of paying a ridiculous amount for someone else to do it.... Congrats!
(And thanks for the update!)
 
Just pulled my switch apart today. I was only getting A/C on 1 and 4.

Anyway, the connector had overheated and started to melt. Inside of the switch was really carboned up. This ought to be a safety recall.

Cleaned all the contacts, and generously applied dielectric grease to the switch internals and the connector. Seems to be working find now on all fan speeds.

There are just too many amps going through that little switch. It arcs, carbons-up, resistance increases, and ultimately, the wiring melts from the heat. I work on old cars (60's 70's) a lot and see this type of issue all the time. Really don't expect it on a late model.

Best solution is to install a relay on the compressor clutch and get the amps out of that switch. That will be phase 2 of the repair. Most late model cars control the compressor clutch with a relay, but for what ever reason, Mazda did not in this case.

Also needed to adjust my control cable. Hadn't been getting the air volume I expected though the dash vents. Air just didn't seem to be coming out of the right places. This became particularly noticeable the last few weeks with the cooler weather and running the heat and defroster.

The cable had slipped. After a couple of adjustments, I was able to get the air flowing to the right places.

My compressor runs with the selector switch in the floor position (and the AC button off). I thought that was odd. Really only expected it to bypass the switch in the defrost positions. Got dark before I could investigate further.
 
OK, so last year I found a solution to the flickering A/C light on certain fan speeds that worked for me and many others.

http://www.mazdas247.com/forum/showthread.php?t=123678787

Basically, squeezing the contacts of the wires going to the fan speed with pliers solved my problem...for a while. The solution could last weeks, maybe months, then return. Well my problem came back this summer and taking 10 minutes to remove the bezel and squeeze the contacts worked...but then I decided to go all the way. I took everything apart and SOLDERED the wires to the fan switch. Now, I don't have ANY problems at all. I used to still get a slight flicker of the A/C light if I slowly turned the fan position switch between 2 and 3. This no longer occurs. The A/C light stays absolutely SOLID the moment the fan switch leaves position 0. I'm gonna post pics tonight or tomorrow. Hope this helps someone. Be cool....

EDIT:

OK, I just added the pics...
FIRST, make sure your key isn't in the ignition!!!
1) the switch
2) I cut the black housing to expose the male contacts
3) Plug-in the wires
4) Solder the wires. Make sure you heat the contacts properly (ESPECIALLY the male) or the solder won't stick properly! Use flux, it helps. This is very important.
5) Hot-glue the S**t out of the entire contacts. Let cool, then glue again. Make sure there aren't any contacts exposed.
6) shown below...wrap in electrical tape for good measure

Ok so i have tried to get at this switch with no avail a couple times now(of course I always try at night....(freak)(hand) So how exactly do you get at this dang switch? I wanna try this fix because I keep blowing my resistor; I have gotten the faceplate off but cant get the F&%'ing switch out! thanks!
 
Ok so i have tried to get at this switch with no avail a couple times now(of course I always try at night....(freak)(hand) So how exactly do you get at this dang switch? I wanna try this fix because I keep blowing my resistor; I have gotten the faceplate off but cant get the F&%'ing switch out! thanks!

if you already got the hvac face off, i believe there are some screws to remove the clear plastic piece, then you remove the switch using a 1/2" socket
 
******* A'!!! i need to try this, living in south florida with only 1 speed working isnt pleasent at all!!
 
btw...i've compared an old switch with one that came from a car w/ working a/c. the flakey switch had a yellowed look to it while the other one was a lot whiter. anyways, if the plastic fan switch housing looks kinda yellow, it has probably been overheated due to the large amount of current flowing through it.
 
I’m still fighting the old fan switch positions 2 &3 problem on my 2002 Mazda Protg 5, i.e. the problem where fan speeds 2 & 3 do not work with A/C selected. I’ve done all of the switch things but the problem persists. My guess is that the electronic threshold points on the logic/control are marginal. It appears that Mazda has ultimately corrected the problem with an upgraded logic control unit (TSB MT000003895). I’m trying to avoid the cost of replacing the unit with a new one.

Do you know what component values were changed on the upgraded logic board(s)? I’m hoping that it is a simple resistance value change. Do you know what the changes are? If the change is internal to the chip well, of course we’ll have to forget that.

If I were to try to purchase an upgraded control unit from an auto salvage dealer what part numbers would identify the upgraded electronics?

Mike O'Hara
Edinburg VA
 
Do you know what component values were changed on the upgraded logic board(s)? Im hoping that it is a simple resistance value change. Do you know what the changes are? If the change is internal to the chip well, of course well have to forget that.

I asked the same thing a few months ago in another thread, with no response.
http://www.msprotege.com/forum/showpost.php?p=4675248&postcount=8

A complete list of controller part numbers was put up by TheMAN a couple of posts before the one I linked.
 
Alright I'm having a similar issue, except that the blower only works on 4! This happened overnight on a super cold day. Is this the same issue as the A/C going off on 2 and 3? Would the same fix work or do I need to replace something?
 
2002 Mazda Protg 5 fan switch positions 2 & 3 problem, a summary of my efforts from Spring 2009 until now (12/14/09);

1 Cool day. Problem wasn’t apparent. Thought at this point was that the problem occurred only when ambient temperature was high and thus not noticed with cooler temperatures and no requirement for A/C. This subsequently proved to be correct….for the most part.
"Ohmed out" all 4 switch positions, all ok. I went ahead anyway and proceeded to remove, take apart, clean, and lubricate the switch. Later, when the outside temps were up and A/C required, the position 2 & 3 problem proved to still be there.

2. Hot day, switch positions 2 & 3 not working. Made a jumper cable and one-by-one provided a switch connection bypass for all 4 positions. The fan and A/C worked OK in all positions. At this point thought maybe there's another problem with the switch...who knows what? So, bought a new switch. Installed the new switch (on a hot day) and all worked OK...for about two weeks!

3. At this point I disassembled the original switch and installed stronger springs as described in this forum. As usual things worked OK for a short while and then the position 2 & 3 problem returned. The problem was noted today (with the temperature in the low 30s) while calling for A/C aided defrost

4. I am convinced that the problem is related to a marginal threshold with the associated electronics, i.e. control circuit board. The "cures" listed above may or may not be effective depending on the specific situation. Apparently the only 100% for sure correction for this problem is to replace (or modify) the control PC set (there are two boards)

Thanks,

MJO
 
Alright I'm having a similar issue, except that the blower only works on 4! This happened overnight on a super cold day. Is this the same issue as the A/C going off on 2 and 3? Would the same fix work or do I need to replace something?

I had the same issue last year. You need to have a resistor pack replaced. It's located behind the glove box. I guess you can do it yourself but I believe you'll have to get the pack from Mazda. Don't remember the pricing...
 
I failed to mention that I had done that also. Actually I haven’t replaced the resistor pack but checked it with an ohmmeter against Mazda service specs (found on the Mazda Forum) and all was OK. My check included heating the pack with a hair dryer. I got it quite hot but the resistance values all remained OK. Besides, the resistor pack is there to set the various blower speeds. Any defect here would affect the operation of the blower motor with or without A/C.

I am amazed at the very detailed and accurate information presented in this forum. I’ve read different sides and potential solutions to this problem (A/C operation intermittent in fan positions 2 & 3…sometimes expanding to position 4). I’m now solidly now behind the replacement or modification of the control electronics (a set of two circuit boards) as the only permanent correction to the problem. Unfortunately it’s expensive ($360) which by the way includes the whole control panel assy.

The following link; http://www.protegefaq.net/tsb/mt000003895.html found in the Mazda Forum, pertains directly to the problem and its resolution. Of course TSB 000003895 doesn’t describe what component changes were made or provide the part numbers of the original and upgraded PCs to allow one to purchase an upgraded unit from a salvage yard. The forum is still awaiting these specific answers. Hopefully someone will come along with this information soon.

Thanks,

MJO
 
I failed to mention that I had done that also. Actually I havent replaced the resistor pack but checked it with an ohmmeter against Mazda service specs (found on the Mazda Forum) and all was OK. My check included heating the pack with a hair dryer. I got it quite hot but the resistance values all remained OK. Besides, the resistor pack is there to set the various blower speeds. Any defect here would affect the operation of the blower motor with or without A/C.

I am amazed at the very detailed and accurate information presented in this forum. Ive read different sides and potential solutions to this problem (A/C operation intermittent in fan positions 2 & 3sometimes expanding to position 4). Im now solidly now behind the replacement or modification of the control electronics (a set of two circuit boards) as the only permanent correction to the problem. Unfortunately its expensive ($360) which by the way includes the whole control panel assy.

The following link; http://www.protegefaq.net/tsb/mt000003895.html found in the Mazda Forum, pertains directly to the problem and its resolution. Of course TSB 000003895 doesnt describe what component changes were made or provide the part numbers of the original and upgraded PCs to allow one to purchase an upgraded unit from a salvage yard. The forum is still awaiting these specific answers. Hopefully someone will come along with this information soon.

Thanks,

MJO
 
as i have stated before, if it was a resister that controlled the fan speed, then why does it only affect the a/c?

I really want to run a temporary switch to the a/c compressor. turn it on that way, then leave the one in the dash off.

if the a/c comes on, and works in all speeds, then i'm just gonna wire up the a/c compressor to the switch in the dash directly, maybe through a relay that is only fed when the hvac is on. then it will work just like normal, but actually work in all speeds.
 
Attached is some technical info from a link that I found on this forum. Check page 3.

Good luck.

MJO
 

Attachments

  • 07-40.PDF
    513.4 KB · Views: 1,418
I just now went back into pasadina commut.s post (above), this time drilling further into “TheMAN’s 6/12/09 post.. Went I went there before didn’t notice the link in the upper right hand corner “How-to: Identifying 2001-2003 Protege HVAC switch unit revision”. There it is, complete with photo, one of the answers, “Rev D” in my case!
Thanks so much pasadina commut and TheMAN.

MJO
 
I really want to run a temporary switch to the a/c compressor. turn it on that way, then leave the one in the dash off.

I have been considering the same thing. Have to wait until it is hot again to do some tests though. The idea I was toying with is wait for the system to stop working on speeds 2 and 3, then immediately disconnect the existing wiring for the A/C compressor, and plug in instead 12V -> fuse -> switch -> compressor -> ground. Throw the switch and see if the fan works. It might not though even if the compressor goes on. Depends what the $#($&#($& circuit board is looking at. Also the most it would do is run the compressor all the time, and I'm pretty sure the controller board is turning it on and off to maintain the proper temperature.

Another option would be to run the existing wiring to a relay, and have that relay turn the compressor on or off. That seems more likely to work, since the current needed to throw the relay should be much less than that needed to directly activate the compressor.
 
Back