I picked up and older Hifonics Z440 and went to power it up and none of the LED's light up. I opened the case and it looks like someone was in here. Iam not sure where to start trouble shooting this one. Here are a couple pictures. Any help would be greatly appreciated. Thank you!
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I see that one mosfet in the power supply misses. Check the idle current, measure the mosfets in the power supply.
When the amp is working normal, idle current is about 1,5A. I understand that it doesn't turn on at all, so it will be very low.
Did you check the fuse?
Looks like the legs have been clipped on one of the rectifiers.
Looks like the legs have been clipped on one of the rectifiers.
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I have .001 when no power on the remote turn on and then around .300 when 12vdc is applied to the remote turn on. The fuse is good and D411 was clipped.
When you connect power and ground of your power supply to the amp you should have 12volts when you measure with your volt meter between power and ground at the power terminals. If you have power there then leave your black probe on ground and check the center leg of the power supply mosfets. You should have 12 volts there. If not then you have a problem with your power supply, the fuse, or an open trace on the bottom of the board.
Was the diode shorted?
This board design is awful if there are solder connections on top and bottom of the board. All connection where there are solder connections on both sides are suspect. They should be desoldered, the leads scraped and then resoldered.
This board design is awful if there are solder connections on top and bottom of the board. All connection where there are solder connections on both sides are suspect. They should be desoldered, the leads scraped and then resoldered.
I have 13.45vdc on the power terminals and 13.40vdc on the center pin of both sides of the power supply mosfets.
What IC is that amp running in the power supply I can’t tell from the photo? That would be the one with 16 legs in the power supply section.
Connect the remote power now along with the 12 volt battery and ground. With the black probe on ground check for battery voltage at pins 8,11, and 12 with the red probe. Pin 12 is connected to the remote turn on voltage. That will make the chip operational.
If you have correct voltage there then check pins 3 and 4 to see if they are below 3.5 volts.
If these pins go above 3.5 volts it will shut the chip down.
If you have correct voltage there then check pins 3 and 4 to see if they are below 3.5 volts.
If these pins go above 3.5 volts it will shut the chip down.
What is the voltage on pins 14,15,16 of the 494 ?
Also what’s the voltages on all 3 legs of the power supply fets
Also what’s the voltages on all 3 legs of the power supply fets
494
pin 14=5.0v
pin 15=2.39v
pin 16=1.402v
fets
pin 1= all around 5.07V
pin 2= all around 13.42V
pin 3= all around 05.0mV
pin 14=5.0v
pin 15=2.39v
pin 16=1.402v
fets
pin 1= all around 5.07V
pin 2= all around 13.42V
pin 3= all around 05.0mV
494
pin 1=2.49v
pin 2=4.60v
pin 3=70.2mv
pin 4=16.2mv
pin 5=1.518v
pin 6=3.65v
pin 7=02.4mv
pin 8=12.63v
pin 9=4.99v
pin 10=4.99v
pin 11=12.63v
pin 12=12.78v
pin 13=5.0v
pin 14=5.0v
pin 15= 2.38v
pin 16= 1.39v
pin 1=2.49v
pin 2=4.60v
pin 3=70.2mv
pin 4=16.2mv
pin 5=1.518v
pin 6=3.65v
pin 7=02.4mv
pin 8=12.63v
pin 9=4.99v
pin 10=4.99v
pin 11=12.63v
pin 12=12.78v
pin 13=5.0v
pin 14=5.0v
pin 15= 2.38v
pin 16= 1.39v
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