: problem with aftermarket cd player

01-28-09, 01:12 PM
hey guys.
when i got this car in november, it had 1 working tweeter, and 1 working 6x9. the radio knobs were missing, and the cassette player wouldn't play anything, so all i had was 2 speakers and FM radio.

i had some pioneer 5.25" that i put on the front doors, and replaced the tweeters with cheapo metra ones from the auto part. at least i could have volume now...

i bought a new Kenwood KDC-MP238 cd player, with the appropriate wire harness and dash kit. took out the old radio, put in this one using the wire harness. it was all plug and play, and it worked right off the bat.

when testing after the install, i noticed that if i cranked the volume too loud, the letters on the cd player would fade in beat with the bass of the song (remember, i have no bass!) and if i went louder, the cd player would shut down. it would then restart and when it got to play again, it would shut down again. and so on.

i thought at first it was a battery issue, but then realized it also happens when the car is on. i had the battery tested at autozone and they told me it's like-new, working perfect. since the cd player still turns off both with the car on and off, i'm doubtful it's a bad alternator.

now I replaced the speakers with brand new Polks, hoping for better sound. they sound better indeed, but i still can't go too loud!

the "sound system" now consists of 2x Polk 5.25s, 2x Polk 6x9s, the Kenwood CD player, and what looks like oem amplifiers in the trunk. still missing more speakers and then the sub/amp to add, but not until i figure out what's causing this issue.

keep in mind i can play with no problems whatsosever for hours on end, just not with the volume cranked too high.

so then the question is, where is the problem? why does it fade and/or turn off? is it because i wired something wrong? is it a lack of power going to the unit? or is it one of the many oem amplifiers in the trunk that turn the whole thing off?

any ideas are greatly appreciated:worship:

01-28-09, 01:20 PM
You should post this down in Technical Tips, Audio/Alarm.....

What year car and model? What OEM sound system? Part of these sytems is also tied into the alarm and theft system, as well as having cabling which also carries serial data between modules. The head unit drives the amps in the trunk, so it sounds as if you have a bad voltage supply somewhere - high volume = too much voltage drain.

That's the end of my total knowledge about the system......the folks down in Audio have all the tricks.

01-28-09, 04:36 PM
sorry for the missing info.

the car is a 1995 4.9L. by "oem" system im referring to the cassette player/fm/am radio combo. no oem cd player. the car originally had 4 speakers on the front doors, 2 6x9s in the rear deck. no middle front speaker and no speakers on the rear doors. im assuming that was the basic audio package?:rolleyes:

01-28-09, 05:01 PM
Something is drawing a lot of power, and the car could be shutting down your unit to protect the battery. Remember that making loud bass notes requires a large amount of power, which means that your system is sucking down a lot of power all at once. See the image below, the large dark blue lines are bass notes, you can see how much the power draw is when low notes come in just by looking.

http://img89.imageshack.us/img89/473/amillidl8.jpg (http://imageshack.us)

The problem: Your system is drawing too much power.

The solution: A variety of things. Try turning off an amp or two. They may be overloading the power system.

01-28-09, 06:07 PM
Maybe it's not grounded good enough or maybe the stock wiring can't handle the amperage of that stereo.

01-28-09, 10:31 PM
so you are saying the grounding was good enough for the oem system yet not enough for the aftermarket?
likewise, enough voltage for the oem system with (originally) 6 speakers, yet not enough for a cd player with only 4 speakers?

how can i go about checking amperage and grounding?:bonkers:

01-29-09, 05:57 PM
why do you have multiple amps for only 4 speakers? My head unit amp alone provides enough power for four tweeters, two 5.25's, two 4.5's and two 6x9's.

01-29-09, 10:23 PM
honestly i am way beyond my capacity here. i only say that i have multiple amps because it looks like more than one unit in the back of the car. i'll take a closer look this weekend to verify. remember, all i did was use the wire harness to wire the new cd player to the same wires the oem head unit was using, so whatever amps that unit was using, i'm using now....right?:bonkers:

01-31-09, 06:10 PM
well guys today i tried fixing some of the many issues. among them tried to deal with the dimming/shutting off of the cd player.

i can now say i'm 99% sure it's not a grounding issue. today (for other reasons) we changed the bolt for the battery ground terminal, and we made sure it was in tight. the cd player was still doign the same thing, so i thought of reinforcing its ground. so now it's actually grounded in two places, through the oem ground (using the wire harness) and to the chassis of the car via another 16-gauge wire i ran to the back of the unit into the unit's ground wire. so its doubly grounded (tested both grounds as well, they are working!)...so then what the heck is it?

i dont want to be paranoid/overexcited, but i think the cd player now goes louder and the bass hits harder before it starts to dim, but its still turning off:mad2:

so, what else can i try?

01-31-09, 06:24 PM
In my opinion is just the quality of the CD player. Theoretically (based on the fuse size) the power wires are able to provide to your CD up to 120W.
You can always run thicker wires directly from the battery to make sure you got all the power you need.

01-31-09, 06:38 PM
that seems like a harsh comment on Kenwood's quality:suspense:

i had a Kenwood DVD player for 2+ years on the maxima and cranked that real loud, and did all sorts of things with it, and had nothing but good experiences. you think their cd player line is not a reliable as their dvd player was?:confused:

02-12-09, 04:13 AM
i belive its the quality of the stereo and how you have it wired. your rdio is spec for four speakers not six also the speakers could be wired wrong. check your polarites and try again go to only four speakers and see if you get the same results. also how many amps you have plugged up.

02-12-09, 09:01 AM
thanks for the replies, but i already fixed my problems with the stereo.

it was a poor connection to the battery. now that is fixed and i can crank it up all the way, though i probably wont ever...

i had to unplug some speakers, 'cause i had 8 Polks, putting 2ohm loads on each channel and it was creating crazy distortion on the signal. until i can afford a 2-ohm stable 4 channel amplifier, i'll keep only 4 speakers plugged in:nono: