Need help with amp problem please

[Akshay 10+ year member]

Hi I have 2 amps being run from my head unit. The one for the subwoofer is ok as the sub is powering up and working. But the 4 channel amp has stopped working for some reason. I've had to remove a lot of rear trim to gain access to it but can't see anything obvious. There is power to the amp, there remote lead is powering up (live with tester) but the light on the amp is not coming on and so the speakers not working.

I have just tried with a different amp and the same thing is happening. Both the 12v and remote connections have power but the amp light is not on and no resulting sound. Don't know why the sub amp is working though.

The head unit has not been touched and the RCA's are all intact.

What else could be the problem as the car is in bits right now.

Thanks in advance.

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[dbertoli]

If you have a tester light try it over the power wire and the ground. Sounds like it may be a faulty ground. If not I would check the fuses. Any fuses involved with the amp.

 

[Akshay 10+ year member]

Hi the fuses are all fine. I checked and I'm getting 12V at the power source and 10V at the remote wire. Just hooked up my subwoofer amp to the RCA's and speaker wires and the sound was working again. But when I used the 4 channel amp it wasn't working again.

I have re-checked the earth and that is fine.

But, and here is the but, I used my spare 4 channel amp, hooked up the power, earth and remote, and the front RCA's and speaker connectors. Replaced the fuse by the battery fused supply and the amp started smoking!! //content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif //content.invisioncic.com/y282845/emoticons/eek.gif.771b7a90cf45cabdc554ff1121c21c4a.gif

I have no idea what caused that but the amp is bought as a used model off ebay. Could there be something seriously wrong here? I've never seen smoke from any amp before.

 

[CrossoverOre 10+ year member]

if its a bad amp it will smoke like that.

 

[robert420 10+ year member]

thats no ****^^^

check all of the fuses.. and possibly upgrade to a higher resistance fuse.. and check the grounds. as well as all of your other connections. its possible that the remote wire could be grounding its self out, causing the amp to not work right

 

[Bass4Days 10+ year member]

Something is grounding itself out or you had 2 bad amps and when u get a good one hooked up it will work. Sometimes a amp will fry even a output and it will still turn on and play. Sounds like you were testing it with a bad amp and as you were trying to give it power it burned up and smoked. Plus I think your remote should be 12 volts not 10. Your amp looks for a 12 volt signal and if it sees a 10 volt signal it might not turn on : /. My 2 cents

 

[Akshay 10+ year member]

I have now taken out the sub (was planning to do that anyway to free up space in the boot) and am using that amp to power my front speakers which are now working fine. The amp is powering up fine with the remote lead running at 10V but not sure why both 4-channel amps were bad.

As a result I now have no rear sound so wondering if a cheap 2 channel amp will sort the problem or if I'll be back at sqaure one!

The remote lead runs all the way to the stereo and nothing has been distubred recently to cause it to short out anyway. Strange huh?

 

[Akshay 10+ year member]

Got it working in the end, when I tried the Infinitiy amp again it all seemed fine, even after smoking the initial time. I think it may have been down to bad earth because before with the previous amp I needed a GLI to eliminate alternator noise. Now the noise has gone. //content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif

 

[Akshay 10+ year member]

Hi guys I now have the amp cutting out intermittently so all sound stops. Is this down to a damaged amp (was smoking before but ran fine afterwards) or is it a power supply/earth problem?

 

[robert420 10+ year member]

has to be something with either the power wiring and ground, or the power source its self. how much total power are you pulling and what size of wire?

 

[Akshay 10+ year member]

Hi the amp is 300W RMS and I have 8 gauge power cabling which was fine for my previous amp.

 

[robert420 10+ year member]

something has to be shorting out, preferably the remote wire... try taking a piece of 18 gauge wire roughly 2 inches long, and touch the remote and 12v. it the amps stays on then its something with the remote wire

 

[winkychevelle 10+ year member]

Replace the fuse under the hood its prolly half blow happens alot with glass fuses

 

[robert420 10+ year member]

which is why i never use glass fuses. i prefer ANL fuses or maxi fuses

 

[tommydh 10+ year member]

un hook all power connections using DMM check each wire to ground to check for shorts

I would also unhook from battery