Amp Going Into Protection Mode

[abu]

I bought an ALPINE amp second hand a few weeks back, it's a V-12 4CH MRV F340 which I was told was in perfect working oder

Hadn't got around to testing the amp over the last few weeks as I don't have any amp wiring in my car but got the chance yesterday to test it in my cousins car. With the +12v, earth and remote wire hooked up, when the amp powered up it stayed on for about 5 seconds then went into protection mode

After about 5 seconds in protection mode it goes back on and again after about 5 seconds or so it goes back into protection and the cycle repeats it self over and over again

Tried hooking up the 4 CH RCA inputs as well as the wiring up 2 speakers to CH 1 and 2 but still the same thing. There is no issue with the amp wiring as it originally runs a different amp, 2 CH Audioline. Checked the wiring and tested it with the original Audoline amp and no issues

The V-12 doesn't seem to blow fuses at all, has a 30A in it and its fine. None of the wiring is shorting nor are any of the fuses giving way. I opened it up to have a look inside; it doesn’t smell or look blown at all. All resistors and capacitors look intact as well as connections from the main 3 inputs, +12v, earth and remote

There is no burnt sections on the main board it self to show its been fried and it all looks 100%

Anyone have any idea's what would be causing this? My friend's amp was doing exactly the same thing, ALPINE V-12 as well but when we took the RCA cables out and the speaker wiring it would power up fine

Amp wiring is all 4g running to a 1 farad capacitor, from the cap its running a 8g power cable to the amp as well as an 8g ground cable

Is there someone I can get the amp checked and fixed if there is a problem?

Any help would be appreciated

Thanks in advance

[-Stokesy-]

One of my mates had this issue on one of his amps, it turned out to be a poor ground. I would check this first, the reason that the audioline amp works could be that as it's a cheaper amp and therefore doesn't run a protection circuit like the Alpine does.

Or, it could be insufficient power running to the amp. Again this wouldn't show up on the audioline.

If you've got a volt meter then you can check this fairly easily.

Note: I have limited experience with Audioline amps, so I'm assuming that it doesn't have the same level of protection circuitry that the higher end amps have.

[abu]

Thanks again Mark, I will give that a shot

Few others on an audio forum have suggested hooking it up directly off the battery. A 4 - 8g cable off the postive terminal of the battery running to the +12v and remote connection on the amp, 4 - 8g cable running from the negative terminal of the battery to the amp

If it powers up that way and stays powered up then it's an issue with the wiring, if it goes back into protection then it's an issue with the amp. They also recommended changing the 30A fuse as it may be 'partially' blown

Will try the above and see how it goes

How much voltage should be running through the wiring? I hooked up my 2 farad capacitor to the same wiring and it was reading around +12v with the car off but when started it was reading around +14v

Any other idea's, feel free to post

EDIT:

Funny thing is there is two amps running off the wiring, the other amp is a ALPINE monoblock MRP-M1000 and it's running fine with no issues!

[turbo_brian]

Could be the amp...

When ever testing amps, first point is to throw it directly on the battery to test, get an RCA to 3.5mm stereo headphone jack cable, plug in a walkman, CD player, or similar, plug the RCA's into the amp, hook the amp up to the battery using the Positive to Positive, Negative to Negative, and then a paperclip from positive to remote (to turn the amp on), and have a spare speaker with some cable running off that you can touch on the terminals for sound.

If it fails when set up like this, you have issues with the amp, but if it works perfectly, you need to check your cabling back.

Amps should run on 12 volts without issues, but ideally 14.4 Volts continuous feed is the aim.

B.

[abu]

Thanks Brian, I will give this a go tonight

If it is the amp is it worth trying to get it repaired or best off just getting another amp?

[Johnney_aussie]

Thanks Brian, I will give this a go tonight

If it is the amp is it worth trying to get it repaired or best off just getting another amp?

I had this same problem the amp (Pioneer 800 watt mono block) kept going into protection mode, so i hooked the amp to different speakers worked fine. It was my sub its was f**ked it was a Pionner 800 watt sub so i thought a better Pioneer 1200 watt champion series sub works great . Just tick off the problems like have you got power running to the amp, running out, ground, check the terminals of both battery and amp are clean, then hook it up to something else, open up your sub/speakers to see if they are f**ked. It took me about a month to really find out what was wrong, cause it would sorta work then not but no way near as good as it use to. Hope i gave you some more ideas and hope its not the amp.

[-Stokesy-]

Thanks again Mark, I will give that a shot

Few others on an audio forum have suggested hooking it up directly off the battery. A 4 - 8g cable off the postive terminal of the battery running to the +12v and remote connection on the amp, 4 - 8g cable running from the negative terminal of the battery to the amp

If it powers up that way and stays powered up then it's an issue with the wiring, if it goes back into protection then it's an issue with the amp. They also recommended changing the 30A fuse as it may be 'partially' blown

Will try the above and see how it goes

How much voltage should be running through the wiring? I hooked up my 2 farad capacitor to the same wiring and it was reading around +12v with the car off but when started it was reading around +14v

Any other idea's, feel free to post

EDIT:

Funny thing is there is two amps running off the wiring, the other amp is a ALPINE monoblock MRP-M1000 and it's running fine with no issues!

Oh, well if the other Alpine is running fine off that cabling then it isn't looking good for your amp unfortunatly

That voltage looks spot on, with the car off you should be getting around 12V and when it's running you should have around 14.4V

You might as well try and replacing the fuse, however; i wouldn't have thought you'd even get the protection light if the fuse had blown, but never having blown a fuse in an amp I can't confirm this.

[abu]

I had this same problem the amp (Pioneer 800 watt mono block) kept going into protection mode, so i hooked the amp to different speakers worked fine. It was my sub its was f**ked it was a Pionner 800 watt sub so i thought a better Pioneer 1200 watt champion series sub works great . Just tick off the problems like have you got power running to the amp, running out, ground, check the terminals of both battery and amp are clean, then hook it up to something else, open up your sub/speakers to see if they are f**ked. It took me about a month to really find out what was wrong, cause it would sorta work then not but no way near as good as it use to. Hope i gave you some more ideas and hope its not the amp.

Thanks for that man, see how I go tonight. Hopefully it's not the amp and it's just the wiring

Oh, well if the other Alpine is running fine off that cabling then it isn't looking good for your amp unfortunatly

That voltage looks spot on, with the car off you should be getting around 12V and when it's running you should have around 14.4V

You might as well try and replacing the fuse, however; i wouldn't have thought you'd even get the protection light if the fuse had blown, but never having blown a fuse in an amp I can't confirm this.

hmm yep that's what I'm thinking..

ah ok that's good then. It's pretty stable the voltage with the car off and on, there's a 1 farad cap in the car which reads almost exactly what my 2 farad cap reads

Will give it a shot, at least this way it will eliminate everything around the amp and only leave the amp it self in question. I'm hoping it is just the wiring man, I don't want to chase up with the guy I bought it off because I have a strong feeling it's not going to get anywhere and I will be out of pocket for this amp..

Thanks for the help again guys

[abu]

OK guys I tested it straight off the battery and it's doing exactly the same thing. Switches on and the light goes blue.. stays on for a few seconds then switches to red, after a few seconds back to blue then it repeats it self again..

Any other ideas?

Thanks