Hey guys

I recently had a few upgrades done to the Car Audio system in a TJ Magna, and now I find the subs ain't working. I had a Sony Xplod Head Unit, Sony Xplod Monoblock Amp and 2 Sony Xplod Subwoofers in boxes installed.

The Headunit is fine as it is still playing music through all the other speakers. I'm not getting ANY bass from either of the subwoofers that suggests to me something has gone wrong with the amp or the wiring.

As it is currently the middle of the night (which is when it occurred) I haven't had the opportunity to see if the Amp is still working (which I would be able to tell by the LED's on it), but I do have an idea. The Magna's ride is VERY bouncy due to some savage modifications (lowered extremely low, 19" rims) and I'm pretty sure I lost the bass over a particularly bad piece of road.

Shortly after it had occurred, I tried making sure some of the wiring was in properly and it felt like it was in the Amp + Sub area, but I don't have too much knowledge of these things.

I think the Amp RCA for the Sub may have disconnected within the dash, but I will have to take it back to the people who installed it to work that out.

Does anyone agree, or have any other ideas as to what has happened?

check connections at the amp itself. make sure all wiring is tight. if the amp is not turning on, check the earth cable that's attached to the body. I doubt both lots of speaker wiring has been ripped out. I also dont think it's anything serious.

Start with the basics, check the wiring, as much as you can, and go from there.

If it was installed recently, get the guys who fitted it to check it, make sure its done for free though.
First, check power, usually green led's. Means its getting power, when the head unit is turned on and playing.

There should be fuse under your bonnet you need to check, or there may be a thin wire from the head unit to turn the amp on, thats if you have no power indicator on the amp.

Confirm the power status and get back to us.

Some other stuff to check

There are usually fuses on the amp itself, check

Does the amp smell burnt.

Are all the wiring (power and speaker) neat with no exposed copper.

Are the rca signal cables stretched, cut or damaged where they enter your boot.

Is the amp getting hot without making a noise.

And I should have said this first, could you have accidently bump the bass setting to off on the head unit while driving.

most likely, u have lost ur ground or main power from the battery.

Check the inline fuse for ur amp as mentioned above. Also check the wiring, make sure there is good contact with the battery, and that the wire is connected properly to the amp. It is very unlikely that ur wire is burnt out, as these days the wires have great volt capacity.

If thats fine, make sure ur ground cable hasnt gone loose.. this happened to me before, was working fine one minute, then the next i had no bass!

The ground cable is usually a wire from the amp to somewhere in contact with the car body that is metal. without this, ur amp will not turn on, therefore not powering ur subs =) if ur amps are seen to be working fine (power to the led light) then make sure ur cables to ur subs are connected properly or in working order.

Oh and dont forget to check the remote wire. The remote wire is usually connected to the back of the deck, so when the car turns on, so does ur amp. make sure that wire is all intact, usually a thin black wire.

good luck!

I've had a bit of a closer look today, and I'm finding there are no lights coming on on the amp, the ground wire appears to be pretty stable on the metal in the boot, and my father reckons the fuse is fine.

I've got to find that receipt asap :-/ Maybe the amp is broken, or its just a bit of a wiring mishap.

Check your fuses then get a test light onto the power, ground a remote wire to ensure they are all doing their jobs.

If there's no power at the amplifier, then the amp should have a large power cable going to the battery's +ve terminal and very close to the battery should be an in-line fuse. Have you checked this one?

But there's a lot of potential causes - the remote wire from the head unit to amplifier may have disconnected - this will stop the Amp from turning on, even if it has power. You didn't play with the head unit's settings and turn the SW OUT to 0 or OFF, did you ? :)

If you are close to 'the hills' I can have a look at it with you and help diagnose / locate the problem. I can't say that I can fix it, but knowing what's wrong is the first step.
(and with luck it is something simple, just tricky to find).

Thanks for the offer, I'm in Campbelltown though

The place that installed it had lifetime install warranty, and the amp has 2 years warranty (with the vast majority remaining) so I don't see any harm in taking it back.

I am just hoping I haven't blown it or anything, which seems incredibly unlikely considering the circumstances in which it stopped working (it wasn't too loud, etc)

check everything i said in my post! sounds like ur fuse under the hood to me

Hi guys, problem is fixed!

I opened the bonnet, and found the power wire had disconnected itself from the battery. It would appear that the crimp wasn't strong enough to hold the wire, so I would imagine it's been falling out over time until this particular knock wiped it out.

Put it back in, tightened the crimp a bit (it's much more solid in place now) and subs were back in action!

Thanks for the help guys.

Good work but with that being the issue i would solder the wire into the terminal aswell as crimping it.

No matter how hard you crimp it, over time the wire will still come loose if not soldered.

Good work but with that being the issue i would solder the wire into the terminal aswell as crimping it.

No matter how hard you crimp it, over time the wire will still come loose if not soldered.

Correct, as you know now, its relying on a join purely held in by pressure. you need a solid physical connection that will withstand anything. Go to an auto electricians and get them to solder the lug on properly.

;1359226']Correct, as you know now, its relying on a join purely held in by pressure. you need a solid physical connection that will withstand anything. Go to an auto electricians and get them to solder the lug on properly.

Or if they have a hyrdaulic crimper get them to stick some hex crimps on there for you.

Those things could tow a car if done properly lol.

Or if they have a hyrdaulic crimper get them to stick some hex crimps on there for you.

Those things could tow a car if done properly lol.

We only ever used that crimper for A/C joints, when we did crimps we only ever soldered them.....I mean eh do SOMETHING other then how you have it now, but personally get it soldered.