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dsp26
26-08-2006, 10:19 AM
Was wondering if the gurus can help me out as my process of elimination has turned up blank.

Firstly, i've previously had an amp in my car.. sold it and retained all the wiring in place within the boot.

i've now purchased a new 4ch amp and the 40amp fuse on it keeps blowing.
- No shorts around the amp
- Battery +ve connected and chassis grnd connected
- tried remote on connected and un-connected
- doesn't require amp chassis to be ground.. just ground terminal to car chassis
- bridged to 2ch to power both front components i have.. still blows.
- tried using 2ch non-bridged and same thing.
- tried turning gain up/down

the moment i connect my battery ground back up the fuse blows. whats the go??

but yeah any insight or things to try that i haven't will be much appreciated!!!
teaseR
26-08-2006, 11:41 AM
Faulty amp
i had that problem to my monoblock fuse keeps blowing up ... dont try bigger fuse amps like i did. i went to 80amps and the power bypass that and blew up the fuse on my amp. was hard to look afor another one as it was old model
... something on the line of MOSFET is screwed cant remember tho
cost me around $140 to fix
hope that helps
EuroDude
26-08-2006, 12:36 PM
Have you tried connecting the positive battery cable AFTER the Negative cable?
What brand / model is the Amp?
dsp26
26-08-2006, 03:36 PM
teaseR: cheers for that, though the fuse i was talking about was the one on the amp already and not the inline one. but was wondering, who/where fixed it for you??

EuroDude: is that the correct way? i always thoguht anything electrical ground goes on last... i'll give it a try though. i bought another 10fuses from supercheap hehe. its a cheapo amp, BUT it was all the safety stuff like thermal shutdown etc... even my remote-on line from deck is fused....
dsp26
26-08-2006, 05:42 PM
also, LED power light doesn't come on once even just before the fuse blows... as i safe to assume then that the short is around the power supply area?
EuroDude
26-08-2006, 05:44 PM
What happens if you only connect the Positive and Negative cables to the Amp, leaving the speakers, RCA's, and remote-in disconnected. Does it still happen?
dsp26
26-08-2006, 08:32 PM
What happens if you only connect the Positive and Negative cables to the Amp, leaving the speakers, RCA's, and remote-in disconnected. Does it still happen?

yep.... also regardless what combination of LPF/HPF/gain i fiddle with when speakers/rca are connected/disconnected.

i just pulled apart the whole amp and pulled out the board... nothing seems to be amiss apart from shonky soldering work.....

does my answer above further confirm a power supply issue?
EuroDude
26-08-2006, 08:59 PM
Yeh sounds like the amp is at fault.

If its a brand new amp, return it to the place of purchase.

Dont tell me you got it from eBay :eek:
dsp26
26-08-2006, 09:34 PM
Yeh sounds like the amp is at fault.

If its a brand new amp, return it to the place of purchase.

Dont tell me you got it from eBay :eek:

all i have to say is... LOL.

although they offered warranty i didn't wanna bother as it will cost me half the unit to send it back... especially at the chance i screwed it hence why i opened it and tried troubleshooting it.

oh well, i'll be posting in the WTB section then. thanks a heap for your help!! at least prob is isolated and i can tinker when i have the time.
dsp26
26-08-2006, 10:41 PM
after looking at the open board further, turns out it was a returned and repaired item evident from the shonky soldering of 2 replacement r402l transistors which regulate voltage as well as a dead regulator diode on the ground end which they forgot to replace. this is what resulted in me blowing 12 fuses on this amp trying to figure out whats wrong
marte
02-09-2006, 05:51 PM
lol so everythings good now?
EuroDude
04-09-2006, 10:00 AM
all i have to say is... LOL.

although they offered warranty i didn't wanna bother as it will cost me half the unit to send it back... especially at the chance i screwed it hence why i opened it and tried troubleshooting it.

oh well, i'll be posting in the WTB section then. thanks a heap for your help!! at least prob is isolated and i can tinker when i have the time.

u get what u pay for I guess. :angel:
rule of thumb, never buy cheap car audio from ebay :p