Rockford Fosgate 1500bd

[mike49504]

I checked them all ill check them once again to make sure they are good

 

[mike49504]

ok checked them all again (outputs)

I only have 1 that measures different

Legs1to2:.598
legs1to3:26.4
legs2to3:.598

Is this defective?

 

[mike49504]

I dont understand this amp.

If i have no outputs in the amp it powers up and idle's fine.

I replaced the output that i thought might have been bad.

If i reinstall the outputs amp draws 60+ amps of current.

Outputs check fine resistors check fine the mic4420's test fine.

Wondering what else it could be?

 

[mike49504]

Perry,

I got this figured out so now with the outputs back in the amp it idles fine.

I checked the Lm6171's and the A2211's I have + - 9.78 on all of them.

i checked the power supply pins and toched everything on the board voltage stays the same.

Anything else i should check before i check the output again and have it blow up in my face once again??

 

[Perry Babin]

What was causing it to draw excessive current?

I don't know what else you could check. The drive signals appear to be OK and it doesn't appear that the amp has any intermittent problems.

 

[mike49504]

I had 1 of my friends help me do a few things on a couple of amps so i can try to get caught up on them.

When he put the outputs back on the mesa strip he had them in the wrong order

 

[mike49504]

Ok i put this amp back in the sink clamped everything down.

Amp powers up and idles fine.

Before i hook a speaker to it and test for output i checked for DC on the outputs and it reads 0.11 volts Is this normal or do i have a problem somewhere?

 

[Perry Babin]

It's a bit excessive but won't be a problem for a sub amp. If you measure the DC voltage directly across pins 2 and 3 of U17, what do you read?

 

[mike49504]

This is the amp from hell I went to measure the voltage across pins 2 and 3 of U17 as as soon i tryed The outputs blew again which probably took out the ic's

 

[Perry Babin]

I'd recommend returning the amp to the owner and refunding his money.

 

[mike49504]

Perry,

I replaced all outputs once again. Also replaced all of the IC'S,regulators and resolder all the joints on the board.

Amp is powerd up and playing perfect for about an hour now.

Finally have this amp working again

Thanks for all your help with this amp.

 

[Perry Babin]

Measuring the voltage on those pins of that IC shouldn't have caused it to fail. I've done it plenty of times with no problems. Are you possibly damaging the FETs when tinning the backs of them or when you're soldering them to the MEHSA strip?

 

[mike49504]

Im not sure. Ive repaired atleast 80 fosgate amps with thoose mesha boards and have never had a problem with any of them.

The guy told me he had it at another shop before me and theyve been in business 25+ years . He said they told him it couldnt be fixed .

Well with your help ive proved them wrong but after alot of time and my own money.

Only problem is i have 2 more of the same amp on my bench for repair also. But i know theese amps very well now.I will probably get to thoose in the next couple weeks first i have to get caught up on other repairs