Grimm0ne

iTrader: (3)

really like this place, still going to hang around after the fact...

figured id fix this before i go and "atempt" another trade in as mine started to give me fits, all i had to do was tap the **** and it would work.

as others have said, the biggest pain is getting the radio out, after that its cake walk. I should of took a picture of what mine looked like under the scope but couldn't get the nikon to focus right but you can see when you go to turn to hot/cold you see the 3 amegos move from the board, hince no heat/ac..
thanks agian.

xtremetreadwear

Excellent DIY! Just did this, took around an hour or two, and the temp control now works perfectly! TYVM!


Soldering will definitely takes some time to learn and is even more difficult without a microscope. There's plenty of online resources to research how to solder. I'm sure youtube is chocked full of intructional videos. However, being an experienced IPC Class 3 military spec solderer, I will give you a crash course on soldering and a list of tools needed to make not just a solder joint that works, but one that is extremely reliable.

Tools needed:
Solder iron - Weller is a good brand for our purpose with well priced, good quality products. 100 watt or better is recommended. Do NOT use less than 55 watts.

Fine point solder tip - Soldering the back side is a breeze with any tip, but the top is harder to get to. Use a small point tip

Flux - Use lots of it. Paste or liquid flux is fine. Any brand is fine.

Solder - Use LEADED solder. 63/27 solder is best. 0.25 diameter

Solder wick - Used to clear the old solder from the holes. any brand is fine

Rubbing alcohol - Used to clean the burnt flux

First, use the solder wick to clear the old solder. The old solder failed and therefore is junk. Get it out of there. Most likely it was lead-free as well, which has a higher fail rate than leaded solder. Do the 3 small pins first. Use lots of flux!

Once the solder is removed, make sure your solder iron is at full temperature. Start with the backside of the board. Make contact with the solder and the joint to be soldered, then apply the heat. 2 seconds of heat is your limit. These boards are low grade and wont stand up to a lot of heat. If it didn't solder fully, you didn't make good contact with the solder tip and the joint for fast, well distributed heat transfer. Try again after 5-10 seconds. Use lots of flux!

Once you have the 3 small holes soldered, fully remove the solder from the 2 large ones with solder wick. Then resolder them to the board. The reason for this order is so the part doesn't come up off of the board. Use lots of flux!

Next flip the circuit board over and solder the top. Be careful not to melt the plastic. Once again, contact the solder with the joint first, then apply heat making sure to have good contact with the tip for fast heat transfer. If you melt the plastic a little bit, don't worry, just don't get to crazy on it. Use lots of flux!

Now you have well soldered solder joints that will last. Remember, when soldering, more is not better. In fact, to much solder can weaken the joint. A hersey's kiss shape is your target when making a solder joint.

Final step is cleaning. If you have water soluable flux, you can just run warm, not hot, water over the board until it's clean. Don't submerge or drench it because the temperature control part isn't water sealed and will corrode. If the flux didn't wash away, use rubbing alcohol or even nail polish remover to clean the flux. Not as critical with no clean flux, but you must take care to clean the burnt flux off the board, which is corrosive.

whitemazda8

im doing this today after work. glad i found this thread. hopefully it will be fixed today.

TBAGG

I know how you feel. I snapped a part pulling out the radio too. I had to use JB WELD to put it back together. it's not as good as new, but good enough.

https://www.rx8club.com/album.php?al...ictureid=32885

lesanaylor

this step didnt work for me , my 2004 RX8 is in the shop $690.00.

mrb1p

When I do the power+scan up trick I can put 0 or 16. Nothing else, and it's always warm Why is it doing this ? I just don't want to take everything out and find out this was not the problem..

SayNoToPistons

iTrader: (8)

It should be the problem... Take it out. It's only a 10-15 minute job.

lesanaylor

i just took mine to Mazda and spent $1074.00, it was to replace 2 boards, best money i have ever spent on my 2004 Mazda RX8

hutch91

my heat stopped working so i found and tried this DIY. I did everything perfectly but still have no heat. When i change from cold to hot or hot to cold there is no difference. Does anybody have any advice for what i could do to fix this without breaking the bank.... I need heat bad, washington is COLD
thankyou so much for the great DIY anyway, pepole like you are what make this site so amazing!

Slidin8

My heat started working after i disconnected the battery for a couple hours and reset the ecu

Unionville_2004_RX8

Is there any way to get more wire to come out? I can only pull my radio out so far that i can only put a screw driver down the back side. I have disconnected the lower 2 connectors already.

JugglerMike

Hey Wingnut

High five man! I got an estimate for $1000 and they thought it was an hvac module!

It took me about 2.5 hours to o through your fix and it works like a dream!

Many thanks!!!!

k_9virus

thanks for this thread specially to TS

JodoKast

Awesome DIY instructions! I was able to confirm that this was the same problem I was having, and successfully fix the issue in under an hour thanks to this post!

Thanks!

Wingznut

iTrader: (1)

Another happy customer! Thanks to my missing-z counterpart!

theashtraysays

+1 on the happy customers. Mine started acting up last week, so I did the radio diagnostic and could tell that was the problem (wiggling the **** jittered the reading).
Took me about an hour and a half, including 10 minutes scrounging through my junk drawer to find a replacement screw for the 10mm "secret" radio bolt which of course I dropped.

Very satisfying to know that I avoided hundreds and hundreds of dollars at the dealer. Thanks again for the DIY.

Tommy Gee

I dont have heater control so how do i check it without that

SayNoToPistons

iTrader: (8)

^... What?

Unionville_2004_RX8

How do you get air to come out of different vents? Take a picture of your centre console. Lets see what your dealing with!

derekfc

i think he means his display is missing so he cant see the numbers.

ive gone through this and replaced with a working unit and still no heat.
started a thread here, if anyone can lend some insight.

https://www.rx8club.com/trouble-shoo...hed%2A-239606/

robert, any ideas?

Tommy Gee

yes it has aftermarket stereo so no display so cant run diagnostics . heater only blows warm out of passanger side vent and barely... ty

mrcomments

You (unfortunately) might have a bad heater core. Did you flush your heater core to get gunk out of it? I did the flush and am going to do this project next weekend, hopefully I won't have to pay the dealership a visit for a new core :l

Vanight

Hey guys, about how many hours is this process for someone mildly mechanical and moderate to expert in soldering? Just want to give myself enough time.

Unionville_2004_RX8

Dude read some comments. It'll take about an hour

THE MECHANIC

I just did that yesterday, it's about 1.5h, and now my heat works perfect, many thanks and great DIY