Rear speakers & sub intermittent/cut out randomly

J

Joe Morgan

Registered User
Joined
May 23, 2017
Messages
12
Reaction score
0
Points
1
Having read every post on this forum regarding the B5 speaker system I've realised that people are very bored of the problems it produces, however, my rear speakers & sub keep cutting out randomly and it's extremely annoying.

I have a non-bose system (I think - will double check today) with an aftermarket Sony HU, using (again, I think) a PC9-401 harness. I've tried the PC9-404 harness and both produce the same results, so I'm 99% sure that's not the issue. All 4 speakers + sub work maybe 60% of the time, but then randomly as I've driving the back 2 speakers + sub will just stop working for maybe 30 seconds up to 15 minutes. Nothing seems to trigger it, other than perhaps when I turn the volume up too high (I've resorted to just keeping it at a low volume as it seems to happen less, but it still happens regardless).

It's driving me insane. I've got basic knowledge of how these sound systems work, but not enough to troubleshoot the problem. I'm going to try and get into the sub today and check the wiring, but other than that (and possibly replacing the HU as it may be overheating(?)) I'm stuck for ideas and hoped someone may be able to point me in the right direction. The front left speaker has blown which I'll be replacing today, but from what I can tell the front 2 speakers are powered separately from the rear 2 speakers + sub.

Thanks in advance!
 
Okay, so after ripping apart my boot and finding the sub/amp, I think the problem is with the amp. Messing around with the wires doesn't seem to anything, so I don't think it's a loose connection. Unplugging the amp (obviously) cuts out the rear speakers and sub.

My thinking is that the power to the amp is cutting out. Just need to determine why. Again, if anyone can point me in the right direction I'd be very grateful!
 
I think you just hit the nail on the head yourself, it has to be power cutting out to the amp. I know you said you played with the cables and it didn’t do anything but how far back did you play with them? There could be a break in the cable closer to the head unit. Have you taken h/u out with it connected and played with it? And did it do it with the original h/u?
 
I had the entire trim in the boot off, didn't seem to be any loose connections. The HU was already in the car when I bought it, so not sure if the original HU had the same problem. I've messed around with the Sony HU before and again there doesn't seem to be any loose connections, although it does get very very hot. Without tracing the wires from the HU under all of the trim to the amp in the back I don't think I'll be able to tell if there's a break in the cable, and I don't really want to have to do that.

I'm tempted to just buy a new HU and see if it's that that's causing the problem. Frustrating that there doesn't seem to be anything obviously wrong with anything, and yet it'll just cut out sporadically.
 
It’s ok you don’t need to take up all the trim. If you have a multi meter you can set the meter to give a tone when you touch the tips together then you find the ends of the cable and put the meter on them if you get a tone then your ok. Obviously make sure you have the ends of the same cable though. If you don’t have one there only £25 get one from halfords or some place. Or get an electrical to do it for you. I’d do that before buying head unit.
 
its either the amp itself, or a problem with the trigger from the car. The aftermarket radio will have a blue wire, which connects to the amp to switch it on. Perhaps that wires poorly connected or shorting out or something?

On non-bose models, the front speakers are driven directly by the head unit.
 
You must log in or register to reply here.
Top
Back