Ive had this amp in the box for over 2 years, last week picked up a used 12" kicker L7 and box and wired everything up with a scoshe loc to the rear speakers on my car, 6awg pos to batt, 4awg ground with no remote cable because i planned on using the signal sensing feature. As soon as i powered up the amp it started smoking really bad
I shut everything off opened the amp and noticed 3 badly burnt IRZ44N transistors and one resistor. I checked resistance on the woofer and one coil is 4ohm the other is open the meter reads nothing.
Any suggestions on my issue? I plan on ordering all new Irz44N and a few resistors, do u guys recommend me replacing any other parts maybe the output transistors also.
thanks in advance
Carlos
I shut everything off opened the amp and noticed 3 badly burnt IRZ44N transistors and one resistor. I checked resistance on the woofer and one coil is 4ohm the other is open the meter reads nothing.
Any suggestions on my issue? I plan on ordering all new Irz44N and a few resistors, do u guys recommend me replacing any other parts maybe the output transistors also.
thanks in advance
Carlos
Here is the measurements of the four output resistors on the form from Perry's link to basic amplifier repair thanks again for your help.
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An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Q506 and 507 appear to be shorted. There could be damage to the components that drove those transistors. You need to remove them and the IRFZ44s so that you can test the driver components. For the outputs, check the resistors.
To test the power supply, remove the Z44s and the rectifier and apply power. Measure the DC voltage on the gate resistors (the end not connected to the Z44s). They should all read approximately the same voltage (~5.5v DC).
To test the power supply, remove the Z44s and the rectifier and apply power. Measure the DC voltage on the gate resistors (the end not connected to the Z44s). They should all read approximately the same voltage (~5.5v DC).
Perry I removed all the IRFZ44s and the 2 in Q506 and Q507, are u saying to remove all the resistors to test them? One resistor in slot R605 I had already removed because it was burnt. Im assuming the rectifier is SF1606G in slot D600 is this correct? Should I remove the other 2 output transistors to test the power supply?
Thanks again Perry
Thanks again Perry
After removing the defective output and power supply transistors, you should be able to check most of the resistors.
Yes. D600 is the rectifier.
When you replace all of the power supply gate resistors (replace them even if they're within tolerance), install them a bit off of the board (see attached). This will help prevent damage to the board if the amp fails again.
Yes. D600 is the rectifier.
When you replace all of the power supply gate resistors (replace them even if they're within tolerance), install them a bit off of the board (see attached). This will help prevent damage to the board if the amp fails again.
Attachments
Perry I checked the voltage at the resistors all read between 4.94v-4.97v (at the end not connected to the irfz44ns) and 4.92 on the other end connected to the irfz44n. Does this mean that everything else on the amp should be fine or are there any other components I should test? I used a small jet ski battery as my power source I hope is sufficient for testing. Another question i got is the rectifier i removed is this likely no good either or is there a proper way of testing it.
Thank you
Thank you
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Thanks again Perry, I checked the small Resistors connected to the output transistors with the number 470 on top.(I believe the ones in slots R505,R506,R513, and R516) They all look good to me but is there a way of testing them with a multimeter? I've been looking for the parts I need on Digi-Key but there are so many options on the IRFZ44N and the IRF540. I already found the power resistors 47EBK-ND but can u recommend me witch thermal grease to use and if I should replace the thermal conductor what should I use. I'm trying to order everything all from the same place and at the same time if possible.
Thank you
Carlos
Thank you
Carlos
There are other resistors besides the ones marked 470. The ones marked 470 are 47 ohm resistors.
You can check the resistors with a multimeter.
I've never used the following compound but it should work.
345-1007-ND
Re-use the old mica insulator.
Post links to the transistors that you're considering buying. There shouldn't be that many options. You want the TO-220 package. Vishay, IR and Fairchild are all reliable manufacturers.
You can check the resistors with a multimeter.
I've never used the following compound but it should work.
345-1007-ND
Re-use the old mica insulator.
Post links to the transistors that you're considering buying. There shouldn't be that many options. You want the TO-220 package. Vishay, IR and Fairchild are all reliable manufacturers.
Perry these are the irfz44n's I found http://search.digikey.com/scripts/DkSearch/dksus.dll?vendor=0&keywords=irfz44n+ and the irf540'shttp://search.digikey.com/scripts/DkSearch/dksus.dll?vendor=0&keywords=irf540+to-220ab could u help me decide witch ones to get.
Thank you
Thank you
Got the parts from digi key on Friday, and soldered everything up the same day. Saturday I put the amp together and hooked it up to the car with a 10" Memphis mojo and it sounds great, only problem I had was the signal sensing feature on the amp, it takes like 30 seconds to turn off when u turn off the car and there is a loud rumble from the sub. I couldn't figure out why it was doing that so I installed a remote wire to an acc slot on fuse block and no more problems.
Thank you very much Perry you're the man
Carlos
Thank you very much Perry you're the man
Carlos
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