krypto

all of a sudden my rear left speaker and sub are not working....I've read from this site that there's an amp in our cars...I'm am electronically skilled, used to be a componant level repair tech...so, if the concensious is that it's my amp(?)....fronts speakers are fine...anybody have a real (not block diag) schematic for the amp? Cause if it's the amp i can repair myslef....probably output transistors.....still gotta check the spk ohms.....hmm....

Not to be obtuse here, but does the amp only power the sub and or rear speakers? If so, guess I have my answer....


Thanks again to everyone for all the help......

Ali SC4

It really depends on which audio system you have.
The Nakamichi has one five channel amp under yout CD changer.
If you have the lexus premium system, you have a 4 channel amp under the cd changer that powers the car speakers and a seperate amp for the sub mounted next to the woofer on the underside of the rear deck.

akmpres

I have the same problem in my 1992 sc400 the right front passanger speaker does not work, the tweeter in the upper part works but the midrange in the door is out, and so is the back right passanger side speaker is out too, and the back left driver side speaker is cracking, but with the Nakamichi sound, i never noticed it untill i had to listen to each one indidualy, how do i fix it. do you guys think they are blown or the amp went out or loose wiring, how do i check?

c_irie

I just replaced my front nakamichi speakers the left one which recently went out and the right one which I replaced about two years ago (still working) the speaker surroung in the left one which is made of foam actually had holes in it as well as the coil seemed to be blown ...two years ago when I replaced the right one the coil was also blown...a new nakamich door speaker cost 180.00 so I replaced them with kenwoods components

lex400sc

akmpres,

You have a blown driver. If you're going to replace it, replace them in pairs.

krypto,

You probably have blown speakers too, as it's unlikely that only two channels went out on the amp. But if the amp is busted and you're going to fix it, consideration this... Because only one of two speakers connected to the left channel is dead, it is safe to say that the input circuit is sound and most likely you're looking at a cold solder break somewhere in the output stage (such as the transistor board). It may be very tedious work isolating the breakage this way, so before you bust open the amp, I would diagnose the problem thoroughly.

If you have a spare car amp, or even a home audio amp, connect speaker wire to it and the front left speaker and feed in some input signal. If you can't hear anything it's probably the speaker. Now do the same with a spare speaker or speaker driver and wire it to the left channel on the amp. If there is no sound here the amp is broken. If you are getting sound on both sides, then it is a wiring problem in the car.

the_ez_rhino

How do you tell the difference between the nakamichi and the pioneer premium?

lex400sc