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

Melted Wires...

When I went to clean my connections, I found that my female plug had been melted in two of the thick wires, I am currently working on replacing them...
Don't know how this happened but I'm sure it was part of the control problem.
Any replies to how this could have happened
Also sorry for the poor pic quality, my regular digi cam is on the fritz...
 

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um. all I can say is wow. I didn't think there was enough power going through those wires to heat up that much. of course, it could've been a loose connection and the arc of electricity flowing could've melted the plastic/metal. again - wow. Sorry to see this man.
 
When I went to clean my connections, I found that my female plug had been melted in two of the thick wires, I am currently working on replacing them...
Don't know how this happened but I'm sure it was part of the control problem.
Any replies to how this could have happened
Also sorry for the poor pic quality, my regular digi cam is on the fritz...

I opened up mine yesterday and have same problem all those contacts has melted just like yours. Called the dealership to buy that connector but they says that they do not sell the contact housing connector. I was curious what did you do to fix your problem. I am thinking about soldering all this contact as it shown in this thread. Please tell me how did you fix yours so I can tackle mine.
 
I'm not positive, but I also believe that the archs of electricity due to improper contact is what caused the melting. I saw sparks when I took a look at my wires while operating the A/C. My wires were also very hot. I can't remember, but I believe that even after soldering, the wires were still warm, but not as bad. And there's no arching once the wires are soldered in place. My advice is to disconnect your battery (or at least make sure your key isn't in the ON position) and solder the wires to the switch as shown. Cut-off the female connectors if necessary. Should work great. I'm the one that originally started soldering these wires and I still no longer have problems with the A/C light flickering. Please let us know what happens! Good luck!
 
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Ok, so mine started the flickering last week, then speed #2 went out completely.

Took mine apart. Tip #1 for anybody else who does this - there are 3 snap in tabs holding the thing together, but they are not all the same. One of these has an indent on the back side, and the other two don't. (It is obvious with the switch in your hand, impossible to photograph though.) Start with the tab with the indent. There you can get a small screwdriver in and pop the tab out easily, then the others come off too. I tried for a while on one of the other tabs, and couldn't get anywhere. Tip #2, measure the resistance between the tabs on the back of the switch, and if all positions work as they should (open when they are supposed to be, shorted to the common in the appropriate position) don't take it apart. Tip #3, if you must take this switch apart open it over a tray of some sort - when the switch finally pops open the little springs and the ball bearing may fall out and bounce away.

Bottom line though, is that the AC problems are not due to this switch. At least not on my car, probably not on most of them. There are only 5 connectors on the back, these are common and speeds 1,2,3,4. If the fan is turning at the right speed then the switch is working. If the AC light is not also on, then the problem is elsewhere. Before opening the switch I had thought that these 5 connectors were used in a more complicated manner, with the AC part separate, but that is not the case.

Anyway, it appears that your switch was in fact defective. When I opened mine there were already two springs in the holes you found empty. Additionally, there is a spring that sits on a ball bearing that lives in a hole on the other side. The ball bearing provides the clicks for this switch as it rolls into the depressions in the casing. In the first picture the parts are laid out in order. Left to right, these are the front part of the case (on the screwdriver, with the 5 detentes for 0->5 visible), the ball bearing, the spring, the plastic piece that fits on the shaft and holds the inner switch plate (with its two springs seated in it), the anterior switch plate, the posterior switch plate and case.

In the second picture the back switch plate, the one attached to the external contacts, is shown. The contacts are all coper, everything else you see is plastic or grease. The inner wiper on the other switch plate moves across the 4 separate pads to select speeds 0 (no connection) or 1->4. It looks to me like in the 0 position both the inner and outer wipers are sitting on plastic.The outer wiper moves on the long continuous pad. There is gunk all over the innards which is probably dielectric grease.

While I was at it I pulled the blower resistor, and it appeared to be fine. (As expected, the blower never failed, only the AC). Once it was off I could see some bits of leaves in the chamber behind it - probably a good place to look for those mysterious "sounds like there is a leaf in my AC" sounds.

My best guess now is that either the controller board is defective, or the AC needs servicing so that it draws less current under high temperature conditions.
 

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Anyway, it appears that your switch was in fact defective. When I opened mine there were already two springs in the holes you found empty.

:confused:I wonder why there were no springs in mine? Is your car '02 or '03? mine's an '02. But my a/c is still working fine. I wonder if there's a way to make the A/C wires not heat up? Maybe route some of the cold air down to the back of the A/C control unit?
 
:confused:I wonder why there were no springs in mine? Is your car '02 or '03? mine's an '02. But my a/c is still working fine. I wonder if there's a way to make the A/C wires not heat up? Maybe route some of the cold air down to the back of the A/C control unit?

Mine is on O3.

The temperature issue is just odd, because it depends on the initial temp of the car. Park it in the sun and the AC is off on positions 2 and 3. Run it on 4 for long enough the problem goes away and it will then run for hours on 2 or 3 with no problems. Doesn't sound like the compressor is screwed up or the freon low, else it wouldn't recover. My best guess is that as the control board ages it becomes more sensitive to temperature. That sort of thing can happen when capacitors age, for instance. If anybody has a can of dustoff (something cold when sprayed) it would be interesting to squirt some in various places (at the control board, on the fan, etc. to see exactly where the heat sensitivity is. My money is on the controller board, with a side bet on the fan motor resistor.
 
My connector was partially melted and 'gunky' with corrosion.

i cut the wires and crimped on new female blades (you need two yellow and three red). Connected them and reassembled. Ops check good. WooHoo!

This post gave me the confidence to tear into it and fix it.

I will say it again! I love this forum! [fistpump]
 
hmmm....i'm going to have to look into this...

i bought my car in the winter and it had the a/c flickering problem (fan speeds work fine though)

i also have a spare hvac control box i can use for troubleshooting...
 
I opened up mine yesterday and have same problem all those contacts has melted just like yours. Called the dealership to buy that connector but they says that they do not sell the contact housing connector. I was curious what did you do to fix your problem. I am thinking about soldering all this contact as it shown in this thread. Please tell me how did you fix yours so I can tackle mine.

I cut out the old female connectors, crimped on new female connectors and just ran the wire thru the cutout holes. But now I'm working on switching my A/C control panel to blu LEDs so it's taking a while before I put it all back together.

Thanks for all your responses!
 
When I went to clean my connections, I found that my female plug had been melted in two of the thick wires, I am currently working on replacing them...
Don't know how this happened but I'm sure it was part of the control problem.
Any replies to how this could have happened
Also sorry for the poor pic quality, my regular digi cam is on the fritz...

I had this same problem, but done what was shown in this thread and had 0 problems works fine, and no more melted plug :p
 
I cut out the old female connectors, crimped on new female connectors and just ran the wire thru the cutout holes. But now I'm working on switching my A/C control panel to blu LEDs so it's taking a while before I put it all back together.

Thanks for all your responses!

I just did this last Sunday. A/C work fine for all 4 position for may be 3 times and now it only works on 1 and 4 position switch. I might have to open again and clean the switch contact inside but don't have time right now. Has to be something else which melts the wire as the other friend says in his answer.
 
This DIY is awesome, much thanks! My switch was flickering on and off causing the A/C to randomly come on and off. I cut the wires from the plug and re-crimped them into steel spade connectors and finished it off with a coat of liquid electrical tape, fixed it like a charm!

-Matt
 
did anyone buy a brand new a/c switch from the dealer yet to fix the problem? Im might just do it.
 
Wow. A year later and still going! Thanks for all the replies and compliments! I'm really glad this helped some of you! It's been over a year since I soldered my wires to the switch as shown here and still zero problems. Post if it worked for you, post if it didn't. Later!
 
Mine was flickering when I would switch it from 1-2,2-3,3-4 etc. I tried all the tricks related to the wiring.. cleaning, tightening, etc and it didnt fix anything. Finally it really broke and would only work on high. I replaced the blower fan resistor and its perfect. No flickering either :)
 
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