P38A Testing a sub woofer speaker.

The paper bit has totally rotted away but the cone bit looks ok. Pic below.
I've googled a bit and tested for a circuit between the + and - and that's OK I think..3 ohms resistance average. Next test is to put a 9v battery on the terminals and see if the cone goes up and down. Haven't got a battery to hand but would it still move with the paper missing? Thinking of glueing new papers on to save a few quid like what @kermit_rr did.

Flossie said:

The paper bit has totally rotted away but the cone bit looks ok. Pic below.
I've googled a bit and tested for a circuit between the + and - and that's OK I think..3 ohms resistance average. Next test is to put a 9v battery on the terminals and see if the cone goes up and down. Haven't got a battery to hand but would it still move with the paper missing? Thinking of glueing new papers on to save a few quid like what @kermit_rr did.
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I've used two layers of toilet paper with puncture repair glue. They've lasted a few years now
I did the same some years ago on some marantz speakers my dad had. Cheap and easy fix.

Flossie said:

The paper bit has totally rotted away but the cone bit looks ok. Pic below.
I've googled a bit and tested for a circuit between the + and - and that's OK I think..3 ohms resistance average. Next test is to put a 9v battery on the terminals and see if the cone goes up and down. Haven't got a battery to hand but would it still move with the paper missing? Thinking of glueing new papers on to save a few quid like what @kermit_rr did.
View attachment 313754

Click to expand...

Careful with the 9 volt battery, only a brief touch is needed to see if the coil moves.

Datatek said:

Careful with the 9 volt battery, only a brief touch is needed to see if the coil moves.

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Roger that.

Mark Piercy said:

I've used two layers of toilet paper with puncture repair glue. They've lasted a few years now
I did the same some years ago on some marantz speakers my dad had. Cheap and easy fix.

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I know you did, ya posts came up on a search, right in the middle of the great toilet paper shortage iirc.
I've logged the suggestion ta.

Speakers tested and all good so I've ordered the refurb kits £6.95.

Personally I would just replace those rotted speakers with decent modern replacements like these

Amazon product

Speaker refurb kits have come so I'll be getting on with that probably tomorrow.
@nigelbb Bust the monthly p38 budget buying a new led boot lamp £14 , that's £20.95 and its only the 3rd .
Getting the whole system working could run into a fair few quid yet.
I still can't find out what would cause the 2nd row speakers not to work, I haven't got the dsp amp in the boot but individual ones in the doors, I believe (need to check that out visually) plus the sub amp.
Hk system, no satnav, so 3? Speakers in the front doors and 2? In the 2nd row doors. Lots of speakers to replace orrepair plus maybe knacked amps too?
The sound system is the only thing left that doesn't work properly.

You can swap the door amps from rear to front to see if it's the amps, speakers, or more likely the connectors in left & right front footwells ?

I've done the white connectors both sides, solder and heat shrinked.
Are the sound system wires in them?

Yes. C207/C357 on left side, and C208/C308 on right side (although the connector numbers change on later cars).

There's also connectors inside the B-Pillars feeding the rear doors, that could be a problem. These also feed the window motors & latches, so any issues there ?

pwood999 said:

Yes. C207/C357 on left side, and C208/C308 on right side (although the connector numbers change on later cars).

There's also connectors inside the B-Pillars feeding the rear doors, that could be a problem. These also feed the window motors & latches, so any issues there ?

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No issues at all. Did have a osr window that worked off the switch pack but not off the door itself which a replacement door switch cured. Pity nanocom can't diagnose ice issues .

Getting the old glue off was a bit of a faff.
Instructions say to glue the edge of the new thingy to the cone edge first, once that's had an hour or so to set, you glue the outer edge of the thingy to the steel ledge of the speaker frame.
Cleaned up speaker

My able assistant applying the glue and getting high off the fumes.

Bits of timber were used to lift the cone up a bit to make the mateing surfaces easier to errrr....mate?
Now drying out.
Next exciting episode to follow in an hour or so. Depends if my able assistant has come down.

And done. With hindsight I should of screwed them back into the sub box for the last bit but pegs hold the clamp ring down OK.

Boom boom.

Now you have to investigate rear door amps, speakers or wiring ?

Meanwhile you need another use for the pegs.

Being as I'm ice clueless, but learning more and more, would I be still looking for other faults with the sub if it still doesn't work? Seems a daft question that but I'll explain.
With the knackered sub speakers I wasn't getting even a pop or buzz, nowt, from them. Only a hearing test though, maybe if I'd got the sub box out I may have seen some movement of the cone.? I can see 2 heavy cables going to the sub mounted amp so I guess I should get voltage there as a test and voltage out going to the sub speakers as another test.
Any idea of what voltages I should expect in and out the amp?
It's also possible that I didn't have the sub woofer enabled for want of a better word. If I press the tone button (2001 alpine) on the radio I get bass, treble, balance (they all work) then sub woofer, when subwoofer comes up am I supposed to press something to enable it or is it on all the time and I can turn it up/down using the rotary knob as you would for bass, treble, balance?
But yes, onto the door stuff next, quite looking forward to it.

if you locate the wires feeding one of the working door amps, just wire them temporarily to the sub amp. That will show if it’s working

It works !. Going to see if I can get the cd player working again. It didn't work when I first got her 2 and a half years ago, took it apart and found a copy cd jammed in it, removed that and it worked great but packed up again at some point as I didn't use it all that often.
I'll look at the door amps/speakers when the weather settles in a week or so.