Who knows my stereo system 1999sl320

[Darragh1]

HI
Who is the car stereo guru who knows my model 1999 sl320 129064...so that I may harass him or her with my annoying questions?

The car has Bose door woofer/tweeter and dash tweeters that dont work
It has a seimens amp and a JVC head unit.
Speakers have been crackily at high volumes but speakers were tested not so long ago and you could turn them up as loud as you like without any crackling.
Recently the sound comes and goes in the door woofer and comes back on when I jolt the volume up and then cuts out again.
Maybe it's my HU ??

Thanks in advance
Darragh

 

[Darragh1]

Things I did to troubleshoot-

1. Plugged my head unit into speakers in a car stereo shop and sound came through both speakers - therefore I think the head unit must be ok.

2. Stripped the right hand door card and removed the woofer and tweeter in the housing - unscrewed the woofer from the housing - put a 9V battery to the +- and it popped out and reversed the polarity and it popped in - therefor the speaker is probably not the problem

3. I removed the AMP mercedes part number-A 624 545 8132 and unplugged the left and right sockets from it which made no difference so therefore the amp is not connected at all - hence the dash tweeters do not work????..and therefore it is not the source of the problem I think.

4. Having cleaned connections and checked wiring for damage I re-plugged the door Woofer\tweeter and the woofer worked - then it cut out and in again and out - a quick turn up of volume and in again and out again - the car was parked and no movement was happening to dislodge any loose connections perhaps....

I have a sense that the HU is the problem - I will take off the knee panel and trace the cable from the door speakers to the back of the head unit but I'll bet that's not my problem. I'll borrow another head unit and install it in my car - ....or maybe it's the speaker, but it cant be but it can but it cant can it?????????????????
I have the car booked in with a car stereo specialist but I want to fix it myself.

 

[Sp!ke]

Your head unit is designed to power 4ohm speakers.

What resistance are your speakers?

 

[Howard]

Aren't the BOSE units 2 ohms ?

 

[Darragh1]

Thank you for the responses SP!KE and Howard-
My bose speakers are 1ohm. All speakers have worked on the JVC HU since I own the car (3 years) - until last week.
The immediate problem of the failing woofer I want sorted with my current set up.
.........Then I can relax with my door card back on and take my ease deciding what I might do with my disconnected amp/dash tweeters and HU.
Regards,
DARRAGH

 

[Sp!ke]

I think you've answered your own question here.

Your aftermarket head unit may have worked up until now but the fact is it is not designed to work with your speakers.

Maybe the system has some resistors inline with the speaker cables or something to compensate ... who knows, maybe its more likely to have blown your speakers.... what you need to do is set it up properly with a head unit that matches your speakers or vice versa.

No point mucking around trying to figure out what the current problem is when you are ignoring the fact that your system is a mismatched bodge anyway.

IMHO you need to either revert back to factory fitted state or rip it all out and do a proper custom install.

 

[Darragh1]

Sp!ke,
The cable leading from the dodgy speaker is fine visually and is connected.
I am on the trail of a spare speaker to save me removing my other door card and visiting a dismantler to borrow a HU to test. I ll get back when I learn anything. I hope the anticipation doesn't kill you.
Thanks and I'll get back,
Regards,
Darragh