blown a2300hct audiobahn amp (need help!!)

[BTNH2144]

I have a a2300hct audiobahn amp. I was hooking up a battery isolator using the same remote turn on lead as the amp so they would come on at the same time. The car was off but the amp was still hooked up. When i used a positive wire from the battery to turn on the isolator and test it, i heard a crack from the amp. I thought i unpluged the remote from the amp while i was testing the isolator, but i didn't. All the fuses in the amp blew, so i replaced them. As soon as i put the first one in the amp caught on fire. I took it apart and one of the smaller transistors blew up. I'm trying to find a replacement transistor but i dont know how to match the numbers. The amp has about 30 transistors half small and half larger. The one that blew up was a smaller one. This is what is one the face of the transistor.

IRFZ48V
I*R 306H
3D 17

The pic is the half with the small transistors.
Thanks for any help.

[1moreamp]

The top number IRFZ-48 is all you need to replace that item with. Its available just about everywhere including e-bay of all places.


Good luck

[Perry Babin]

You can't simply replace the single transistor. You must replace all of them that are in the same supply as the one that blew.

You need to check the ones in the other supply also to see if any have failed. Measure the resistance between the first and second legs of each power supply transistor. None should read near 0 ohms. If they do, the transistor is defective.

After you replace the FETs, you need to power up the amp through a 10-15 amp fuse (in series with the B+ supply line). Clamp all of the transistors to the sink BEFORE applying power. If there is another fault, the new FETs can fail within seconds. If the transistors are clamped to the sink and you use the small fuse, the new parts will likely survive and you'll only have to find the other fault. Without these precautions, you'll also have to replace the new parts (again).

Since you have to order parts, I'd suggest ordering a new power supply driver IC (TL494/594?) and new driver transistors (marked a1266 or a1023?).

If you pull all of the defective power supply FETs and power it up, you can do a few tests to determine if the power supply driver circuit is working properly.

[ppia600]

Have fun swapping all those mosfets.Hopefully you don't have to swap the power supply rectifiers too. I just recently got the same amp going with the help from Perry and justonemoreamp. Hopefully the guy doesn't fry it, so far he hasn't. Very helpful guys here

[Safe_Cracker]

It is an audioblah amp, is it really worth it in the price of parts? Polo..

[ppia600]

Originally posted by Safe_Cracker
It is an audioblah amp, is it really worth it in the price of parts? Polo..

I'm definately not a fan audiobahn, but some people have been known to pay $150 to get 'em repaired.

[BTNH2144]

Thanks for the advice, just one more question though. The transistor that blew was IRFZ48V. Do I have to get that exact model number or could I get a IRFZ48 or IRFZ48N? I've found a IRFZ48N.

Thanks for your help.

[Perry Babin]

The 'V' is rated for higher current than the rest. It would be best if you use those as replacements. Digikey has them.

[Safe_Cracker]

http://www.mouser.com/search/Product...ey512-RFP70N06

[Perry Babin]

Those will probably work but it's always best to use the exact replacement unless you have the knowledge and test equipment to know if the replacements are working properly.