I have an Alpine CDA 7856 model that puts out a whopping 16 watts RMS. Whenever I have the radio turned up to a good volume, the lights that illuminate all the buttons on the faceplate dim with the music. Doesn't matter whether it is bass or treble. I have heard of some people adding a ground wire to the back of their radio and running it to chassis ground. Will this help me or do I have another problem? I want to find out what it is because I just ordered a new head unit, and don't want this same problem to happen. I look at it as the radio isn't being supplied with enough power to keep the lights illuminated fully all the time. And if the small amount of power required to light the faceplate isn't there, it makes me wonder if my speakers are getting the full amount of power from the radio in the first place. Any help/ideas/opinions are welcome.

 

did you attach it all to the stock wiring or did you make a new battery connection directly from the bat to the headunit with a fuse?

just asking this because my CDA9815 required a separate battery line directly from the battery to work properly as well as a separate ground from headunit to chassis.

 

I had it installed at a stereo shop because I am colorblind. If it needed to be hooked up to the battery directly, they would have done it. Supposedly, all the radio needed was the aftermarket wiring harness and GM antenna adapter to make it all work. I have had that cd player in the car since Christmas of '03. The whole time that I have had that cd player, I have also been running an Orion amp and 2 JL subs. I have since taken the amp and subs out to redo all the rest of the audio stuff with new head unit and speakers and stuff, but still noticed this problem without and of the high powered components.

 

well one way to check is if theres a lead directly off either battery lead with a fuse or a wire directly hooked up to the battery. not all installers do things correctly and sometimes skip that part. about the wiring harness all that is, is a plug that will go into your stock wiring so if you decide to change the radio back to the old factory radio, you just plug it in and play. with my car i do not have a wiring harness in it since the adaptor/connector was cut out by the last owner. and if he used the power lead which is incorporated into that connector, you may have to run your own line to the battery and run a new separate ground to the chassis.

 

That HU dosn't require a direct connection to the battery. It might help but I doubt it. Some HU just have that problem just due to the design.

 

Like 9177 said, that HU doesn’t pull a lot of current. But a 12-gage wire to the battery and better ground may help. Only thing to do is try.

 

The use of an external amp would most likely cure the problem. Most of the time the power to run the internal amp will make the lights dim when turned up.
Will

 

even if your lights didn't dim, maxing out the internal amp will cause it to heat up greatly, and also cause clipping...

on my pioneer, I can essentially limit how high the volume goes... so my maximum setting is slightly below the point where my speakers start sounding like crap...

 

Could be several things...

If they did use the factory wiring (which there's a good chance they did, depending where it was installed), that could be your problem... Face it, our cars are old!

Do you have any problems with lights dimming on idle while listening to your hu? Is you voltage meter lower than it should be, on your dash? Your alternator could not be putting out the amperage that it should be, and that could be at fault.

Or it could just be a bad internal amp in the headunit itself.

I'd say when you get your new hu, have it hooked up, and if it's still doing the same thing, go to a respectable car audio shop, and have them look into it. If you're just running a headunit, there's no reason you should be having dimming issues, unless like I said, your alternator is on it's last leg. Don't take it to like a circuit city or best buy... those guys don't need to be MECP certified to get a job installing, and honestly, I've seen some of their work... we spent a lot of our time correcting their messups... Go to a local shop, or maybe a tweeter, and make sure their installers are at least certified!!!

Good luck man... hope you get it fixed!

 

not necessarily... I've seen cars with good wiring that dim the lights in the car, as well as the lighting on the headunit itself... this is definitely no power hog... the wiring was hooked up right, and the battery fine. I just think that when some head units try to put out bass to 6x9's or what not, it just takes a lot out of 'em...

lukily our cars require subwoofers, so I have an amp for bass.. no worries there.