If your car amplifier is not providing any sound or power and the wiring side of things is perfectly fine, chances are the amp is in protection mode due to being blown. A blown car amp can have many possible causes it can be a mechanical failure interms of wear and tear on the parts or accidentally. Here are the top common causes that blows out a car amplifier.
1) Crosswirng power and ground wires.
2) Too low ohm impedance.
3) Clipping running into a distorted signal, basically gain not setup correctly and turned all the way up.
4) The speakers wires accidently shorted.
5) Amp being mounted onto the box parts internally getting damaged from vibrations from the subs.
6) Overheating.
Now that you are aware of the different causes, it will give you an good indication to whether or not your car amp is blown out. Before we explain how you can fix it, ensure that the amp is getting at least 12 volts by using a digital multimeter to measure the volts at the terminals on the amp. If the voltage is 12 or higher thats fine. Now the most common part that blows inside a car amp is the mosfet transistors. All you need to do is look at your amps service manual which you can find online and find out the type of FET Mosfet transisters it takes. Then you simply test which ones are bad with a multimeter and replace them one by one. Most likely takes around 15 minutes to complete if you are good with soldering.
1) Flip the amp over and remove all the screws holding down the back panel.
2) Lift of the panel and place it to a side.
3) Locate all the mosfet transistors. There will be usually at the top or bottom in blocks of two mounted onto a metal heatsink held by a clamp and a screw.
4) In most cases you will need to remove the circuit board from the amp. There will be screws holding it down, unplug any connectors if you need to. Remember to take a picture of the amp before hand so you know how to put it back together on your phone. This will makes things easier for you later on.
5) Use a desoldering pump to remove the old solder from the mosfet transistor. Now that it is removed, test for shorts by setting your Digital multimeter to ohms between all three pins. That way you will know which ones to replace.
6) Cut the legs of the new mosfet transistor and position it into inline with the section on the circuit board. Using a soldering iron, solder down the three points neatly, ensuring that the connections don't bridge across.
Do the same procedure for all of the different mosfet transistors. Replacing all the bad ones will 99.9% fix your blown dead car amplifier the very first time. So definitely give this an attempt if you have a dead amp that you want to fix but don't want to send it in for an expensive repair. If you need any help or have any questions then please let us know in the comments.
My amp will power up I hear the relay click on the protect light combed on then goes off but the green power light so vvt com be on idk if that light is blown but I gave no sound output. My fets seem fine none burned and they seem to measure the same on my multimeter idk what else it could b. Any thought appreciated. Thanks
ReplyDeletei recently bought a amplifier jbl gtr 1001 it doesntsound right every timei connect the rca you here a louad thump but it only happens when i connect the left one so i opened te amp everything looked good so i removed the circuit board from body and on the circuit board you can see a capacitor that got burnt i want to replace it but itgot to burnt that i dont know what capacitor to replaceit with my question is do u happen to knowwere i can get a picture or anything to tell me whats the part number for that bad capacitor
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