QuestionQUESTION: I have recently upgraded my car sound system. I purchased a
Pioneer Premier DEH-P400UB, 4 Alpine Speakers, 2 Bazooka
10" Subs, all hooked up to a Boss D1800 1800 Watt 5 Channel
Amplifier. I let a store around me with a good rep. install
it. I picked it up, and everything was just fine, it all
worked properly. I was driving it home and it just cut out.
Everything was powered and my head unit was saying it was
playing but no sound came from either my speakers nor my
subs. I got home and checked my amp, it was hot. I figured
I would just let it cool. After a little while I turned it
on and everything was fine again, I could turn everything
up loud with no problems. The next day again everything was
fine. I don't drive for long periods of time, but after I
dropped off a friend it cut out
again. I thought that it was hot again. I checked it, and
it was warm not too hot, but let it cool anyway. 2 hours
later I came outside and no sound again, the amp was cool,
and there was still no sound even though my head unit said
it was playing. I took it to a friend who knows a little
something about car audio and he took a look at it. The
fuses were good, the wiring was good, everything seemed to
be hooked up fine, but still no sound. About an hour of
fussing about trying to find out what it could be we turned
it on and sure enough we got sound. I turned it up and it
cut out. We knew it had to be the amp, but what I was
wondering is if it is something else. Maybe the amp is
getting too hot, or the amp has some kind of technical
problem and I need to send it in. What do you think it
could be and what should I do. The place that installed is
not open on Sun or Mon so I cant take it to them.
I have a 1993 Jeep Cherokee Country
ANSWER: Here are a some possibilities.
ONE: The amp could be defective; the protection circuit itself could be malfunctioning or something triggering it to shut down the amp. In this case you will need to return the amplifier and have it replaced under the store or manufacturers warranty.
TWO: The amp may not be defective, but there could be a short or intermittent short in one of the speaker runs between the output of the amp and a speaker. Also, there could be a shorted voice coil in one of the speakers. So check out the wiring and look for trouble. If you suspect a bad speaker, try this: Disconnect all speakers at the amplifier. Run sound through the amp to see if it goes down with no loads. Then, connect only one speaker at a time. If one of the speakers is defective it will cause cutout when you connect it and run some high energy program to it.
THREE: Another possibility is the dc voltage from the car electrical system is drooping too low and causing the amplifier to drop out. If this would be the case, you may have to put in a high output alternator and stiffer battery. You can test this hypothesis by turning on all the lights (high beam) and heater to max and see if it causes the amp to cutout.
Try these ideas and let me know more if you don't find the solution.
C
---------- FOLLOW-UP ----------
QUESTION: I tested each of the three you had, still no sound. The amp is cool and not in
protect mode. It turns on along with my headunit. It's just not generating
sound. It worked perfect yesterday. I could turn up the volume all the way but
today when I turn it on, nothing happens. It says it's playing but no sound. I
have not changed anything since that last time. I looked online and it seemed
only people with pioneer head units had the same problem as me. Is it
something with pioneer? Please help.
ANSWER: No, I don't think it is a Pioneer default.
It could be the amplifier has been damaged due to overdrive.
Do you know how to bench test or test in-place?
ONE: Obtain a portable cd player, mp3 player or radio player that has headphone outputs. Get cable that will go from output to rca inputs on the amp. Disconnect cables coming from head unit.
TWO: Disconnect all speakers except for one.
THREE: Remove power from amp for 30 seconds to reset it. Then: Power it up and use input from portable player to drive the amp. Listen to speaker on same channel as input.
If you do not get audio then amplifier is defective (or in protection mode).
If you do get audio that will prove out the amplifier. Then, you must go back and find out why you are not getting audio when connected to the system. (Head unit not putting out? Amp in protection mode anyway? Remote wire not turning amp on? Etc.).
See how it goes.
C
---------- FOLLOW-UP ----------
QUESTION: Well I went back out to test my amp, and for some reason it
started working, I got sound. I turned it off, and back
again and got sound again. So I was curious if how loud I
could crank it, I got it up to 41 out of 62 before it cut
out, and now won't turn on again. I think something is
loose in the back of the head unit maybe. What do you
think.
AnswerYes, it is going into overload or protection mode. It takes some time for it to clear itself.
The question is what is causing this.
ONE: Could be some wires crossing each other or touching.
TWO: Could be a speaker that is too low in impedance (speaker must be equal or higher than the impedance rating of the amplifier).
THREE: Could be caused, for example, if you have two speakers in parallel on one amplifier.
Why don't you remove a couple of speakers or the sub and see if it makes a difference. This will tell you if the amp is going into overload.... may take some further experimentation to get at the cause.
C
PS: By the way, those two Bazooka subs could be causing overheating if they are in parallel on one amp and, depending on their impedance, could be a problem. So, check the impedance ratings and hookup for improper impedance matching to the output of the amp. The Boss amp should be able to handle a 2ohm load, but if the Bazookas are dual voice coil and all in parallel it could be a problem for the amp. So, check those out carefully.
