Bought my 05 Shinka this past May. The Head unit has a mind of it's own. Most of the radio buttons don't work. I can get the CD player to work from the steering controls if I press buttons on the radio while pressing buttons on the steering controls but only the steering controls will work. Turned the headlights on today because of rain and it goes crazy. It changes from CD to Radio to all the other options like crazy. All I hear is the speakers beeping. Sometimes it will change my air from feet to defrost all on it's own. When I turned the headlights off it stops flipping out but I still cant use the controls. What the hell can it be that I can do to fix this so I can save myself a trip to the dealership? Maybe a bad Head Unit?

 

Oh yeah forgot to include that the center dash speaker is always on and it's nothing but static. Only the door speakers and tweeters work. None of them are blown.

 

You have a bad grounding point somewhere. If the issues are specific to the dash, find out where that ground is, remove it, clean it, and re-attach securely. If this is also affecting other stuff like steering, headlights, etc... then start with cleaning the battery terminals and clamps (disconnected) and reconnecting securely.

 

The battery terminals are good. Wheres a good place to start? I'm guessing the head unit. Since the Bose has extra amps could the problem be in their grounding?

 

take the head unit out, and MAKE SURE the face plate's mounting bolts to the back is FULLY secured. there is like 10 or 15 of those small little computer-type screws/bolt.

and of course, check all connectors for broken pins, especially the 2 connectors between the face plate and HU.

 

having same/similar issue -- did you ever get this fixed? What did it end up being? -- All fuses looks good, and too many different ground points for me to track effectively unless I know which way to head in. Already pulled radio and dusted out all connectors... same thing.

 

Haven't figured it out yet. It's actually gotten worse. The front center speaker is LOUD static now and the door speakers quit working. Had to pull the fuse so I could concentrate on driving. I've check all the grounds and all are good. I pulled the head unit and check all wiring and everything seems normal. Last thing I tried was taking out ALL the amps and checking the circuit boards for damage. All looked normal. I'm hoping the problem isn't in the wiring harness. I'm gonna start replacing the head unit a little at a time. First thing will be the cd player. It's all pretty pricey so I'll probably buy used things untill I find what it is.

 

@Alupis I looked at your thread Driver Door Speaker Cutout and (I'm gonna do the same thing) I'm pretty sure it's just a faulty amp. I pulled mine and din't see anything visible but it's hard to see through that epoxy. I've seen them on mazmart for a hundred bucks. If that's your only problem then this would probably fix it. Here is the link... Try it out. Mazmart Shopping Cart

 

lol... i actually never got around to doing the amp swap due to the cost (such a small part! so expensive! damn rx8!) lol.

BUT!

I got into the mood to start fixing things again the other day (the little things were adding up on me...) -- so i did the DIY heater fix by pulling the radio and re-soldering the points on the dial's circuit board -- saved me $350 for the circuit board cost plus labor at my local mazda dealer...

So i started researching my door amp problem again....

Now with mine, my radio will "power cycle" every so often, as if there is a loose ground or something. I can usually hear my radiator fans kick on then the radio goes off, sometimes for minutes, other times it just reboots. Very frustrating -- after crawling the forums a bit, some people seemed to suggest that if you have a bad door amp, it could be shorting and sending power back to the head unit -- causing this exact behavior (as well as a lot of other very strange and unexplained stuff to happen).

So this means, --- fix the amps, which will fix the head unit and your other sound-problems (in theory)...

So i did some more research, and stumbled across this nice DIY:

https://www.rx8club.com/do-yourself-forum-73/diy-bose-speakers-doors-not-working-$1-67-relay-fix-218790/

Basically, the part that has failed in the door amp is a super cheap relay, that you can replace if you have some soldering skills (or a buddy that does). Spending $10 on some relays and a few hours of your time may just very well be worth while before you drop a couple hundred on new amps. Worst case scenario -- you bust the amp -- and have to buy a new one -- however that is pretty much the same place you are in right now.

I'm going to try it this weekend if the relay's arrive in time. I"ll post back if something awesome happens...

 

Ahhhh.... guess I never really thought about that. I can solder as well, but haven't had too much experience with it. I got a kit to do it with so if it works for you, let me know and I'll try it out.