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I screwed up

Hello,

I bought a Profile AP740 Car Audio Amplifier and could not get it to turn on. I had 12.7VDC reading between the power and ground wires (8 G), and I had 0.1 ohms of resistance between the ground point and any bare chassis around it.

I could not get it to turn on, even after trying to bypass the remote turn-on lead by putting a little 16G wire between the B+ terminal and REM terminal to bypass the head unit's turn-on thing. It still would not turn on.

Well, I screwed up bad. After all of this and a lot of frustration, I disconnected the amp and inspected it and all that stuff. I started to put the wires back into it and I put the ground in the B+ terminal and without realizing this, I put the Power cable in the Ground terminal. It made a spark and I pulled the power/ground cables out realizing what I had just done.

Is the amp fried now? Any hope of it working again? What exactly did I do to it? I wonder if the amp was even working in the first place because it wouldn't freaking turn on!!

Thanks for your time

Reply to
pruitt4
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It looks like it was fried before.

Again ? It wasn't working originally was it ? Did it ever work ?

Graham

Reply to
Eeyore

See if you can convince the people you purchased it from that it was faulty when they supplied it to you (is there any evidence that it was not?)

Many places budget for replacing units accidentally destroyed by customers, so they won't ask awkward questions - it's a cheap way to advertise.

Bye. Jasen

Reply to
jasen

Circa 12 May 2007 10:33:17 -0700 recorded as looks like snipped-for-privacy@clemson.edu sounds like:

Yeah, baby!

Reply to
Charlie Siegrist

Reversing power leads on a consumer 12 volt car operated device ain't necessarily the end of the world (but it could be).

They frequently incorporate a reverse biased diode inside the unit for just that protection since there are idiots out there who will reverse connect battery jumpers, chargers and switching transients may go below ground in a car.

You may just need to replace a fuse.

The internal diode may be shorted as a result - and is easily replaced and a power trace on the board or internal fuse may be open. You have to open it up to check that stuff, and opening it may void a warranty. Some manufacturers depend on the vehicle fuse or an in line fuse on the power to the radio.

Your best course of action, after checking the fuse, is probably to return it and let the retailer send it back as defective, but that is your call and depends on your circumstances and those under which the purchase was made.

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Reply to
default

default wrote in news: snipped-for-privacy@4ax.com:

*snip*

*snip*

It's not just idiots who connect the polarity wrong! Diodes are cheap protection for crossed wires.

Puckdropper

--
Wise is the man who attempts to answer his question before asking it.

To email me directly, send a message to puckdropper (at) fastmail.fm
Reply to
Puckdropper

Of course.

I figure I'm not an idiot.

I built a relatively complex "one-off" tachometer for my motorcycle. Used no diodes and still connected it backwards... (in my defense, the wire colors were bleached out by the sun, after a few years - but I should have double checked). The only thing that died was the first eight volt three terminal regulator - and it died shorted, protecting the rest of the linear ICs and five volt regulator.

Reverse bias diodes are cheap protection. I am a believer; oh yes, yes I am.

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Reply to
default

If I read this right, it never did work no matter how it was hooked up. Take it back and tell them it didn't work, you want your money back, a replacement or the unit fixed. Any reputable merchant will stand by his merchandise and take care of you. Don't go into details about reversing polarity, it doesn't matter. If you bought it on ebay or from the back of a pick-up truck at the swap meet you may have a harder time returning it but still try.

Reply to
Bob Eld

If the whole thing was bolted into the car at the time, the ground path was probably from the ground terminal to the chassis to the frame of the car. If you didn't melt the connector itself, you may have had no effect on the amp at all.

--
Ben Jackson AD7GD

http://www.ben.com/
Reply to
Ben Jackson

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