That's very strange. There's no continuity between B+ and the secondary windings (you stated that they read OL to the B+). It blows fuses with them in the circuit (only B+ ang ground connected) but not with them desoldered (b+ and ground connected, with or without remote connected). Is this correct?
Have you replaced all of the power supply FETs or only one?
If you replaced only one, remove that one. Desolder the pads and confirm that there is no 0 ohm continuity between the adjacent pads. Does it still blow the fuse with only B+ and ground connected (secondary windings soldered in, extra potentiometer and resistor out of amp)?
Have you replaced all of the power supply FETs or only one?
If you replaced only one, remove that one. Desolder the pads and confirm that there is no 0 ohm continuity between the adjacent pads. Does it still blow the fuse with only B+ and ground connected (secondary windings soldered in, extra potentiometer and resistor out of amp)?
Perry,
It blows a fuse w/ or w/o the remote on. With the secondary soldered in only.
I only replaced the bad FET. After I replaced that the readings are exactly the same on all the FETs on he bad and the good amps.
If you want me to take that FET out I will and then try to power it up with out it. I really don't think its that because now all the readings are the same. I feel it is something else but I really not good at this.
There was so much continuity between B+ and ground that it shorted out a blue top Otima battery with over 700 cranking amps and then shorted out my MBR70 (Orion batery isolator) and then discharged 3 1/2 far. caps.
Thanks,
Sean
It blows a fuse w/ or w/o the remote on. With the secondary soldered in only.
I only replaced the bad FET. After I replaced that the readings are exactly the same on all the FETs on he bad and the good amps.
If you want me to take that FET out I will and then try to power it up with out it. I really don't think its that because now all the readings are the same. I feel it is something else but I really not good at this.
There was so much continuity between B+ and ground that it shorted out a blue top Otima battery with over 700 cranking amps and then shorted out my MBR70 (Orion batery isolator) and then discharged 3 1/2 far. caps.
Thanks,
Sean
If you replaced only one, remove that one. Desolder the pads and confirm that there is no 0 ohm continuity between the adjacent pads. Does it still blow the fuse with only B+ and ground connected (secondary windings soldered in, extra potentiometer and resistor out of amp)?
Perry,
I desoldered the one FET and cleaned the pads. This is what I measured....
0.852 M ohms between pads 1 & 2
0.635 M ohms between pads 2 & 3
84.5 ohms between 1 & 3
Should I clamp it down before I try to power it up?
What fuse should I use?
Thanks,
Sean
I desoldered the one FET and cleaned the pads. This is what I measured....
0.852 M ohms between pads 1 & 2
0.635 M ohms between pads 2 & 3
84.5 ohms between 1 & 3
Should I clamp it down before I try to power it up?
What fuse should I use?
Thanks,
Sean
Perry,
I powered it up(fully) and it works I got sound and LED comes on! Not sure if its clean sound or not. I didn't want to turn it up. I only had it powered for a short time.
What should we do next?
Thanks,
Sean
I powered it up(fully) and it works I got sound and LED comes on! Not sure if its clean sound or not. I didn't want to turn it up. I only had it powered for a short time.
What should we do next?
Thanks,
Sean
What FET did you install in place of the blown one?
If it's all clamped down, let it play for a while as loud as it will with the 15 amp fuse.
If it's all clamped down, let it play for a while as loud as it will with the 15 amp fuse.
Check the FET that you pulled out. With the meter set to ohms, do you read anything other than OL when you place one probe on leg 1 and the other probe on either of the other legs (out of the board)?
What about from leg 2 to the other legs?
Where did you buy them?
What about from leg 2 to the other legs?
Where did you buy them?
Perry,
It plays loud and clear!!!!!!! Never blew the 15 amp fuse. I'm only using this amp to push my front separates (4-ways, 4-tweets, 2-4.5” and 2-6.5 ).
Thanks,
Sean
It plays loud and clear!!!!!!! Never blew the 15 amp fuse. I'm only using this amp to push my front separates (4-ways, 4-tweets, 2-4.5” and 2-6.5 ).
Thanks,
Sean
Perry,
I get OL when I probe 1 to 2 & 3. But when I probe 2 to 3 I get 2.6 M ohms.
Thanks,
Sean
I get OL when I probe 1 to 2 & 3. But when I probe 2 to 3 I get 2.6 M ohms.
Thanks,
Sean
It appears to be OK. Do you think you may have had a solder bridge? It's very easy to do along the edge of the board.
Perry,
I don’t think I got any solder bridge. I check a new IRF3205 and all the reading were the same except pin 2 to 3, it read OL on my meter. It didn’t appear to have any resistance. Is this normal? What should we try next?
Thanks,
Sean
I don’t think I got any solder bridge. I check a new IRF3205 and all the reading were the same except pin 2 to 3, it read OL on my meter. It didn’t appear to have any resistance. Is this normal? What should we try next?
Thanks,
Sean
The reading from leg 2-3 will vary. As long as it's not reading in the thousands of ohms (or lower) and it's OL from leg 1 to the other legs, this type of FET is generally OK. That said... I wouldn't reinstall the one that you pulled out.
Did you do anything other than pulling out that FET between the time it was blowing fuses with only B+ and ground connected and now?
Did you do anything other than pulling out that FET between the time it was blowing fuses with only B+ and ground connected and now?
Perry,
All I have done is pull out that FET and desolder that 3 wire set. I will put the FET back in and try again.
Thanks,
Sean
All I have done is pull out that FET and desolder that 3 wire set. I will put the FET back in and try again.
Thanks,
Sean
Perry,
I’m total LOST. Ok so I did everything like you said and powered up the amp and it work great!. I guess it was a solder bridge because after I solder the 3205 back everything worked fine.
Then I assembled the amp, put the bottom and side plates back together. Applied power and ground and then the 2 30 amp fuses blew on the side of the amp. Check for continuity between B+ and ground and got 0.6 ohms. Then I took the amp apart again and checked. I am right back to where I started from. That 3205 is bad now and maybe more. I really don’t have a clue why this happened. Any Ideas?
Thanks,
Sean
I’m total LOST. Ok so I did everything like you said and powered up the amp and it work great!. I guess it was a solder bridge because after I solder the 3205 back everything worked fine.
Then I assembled the amp, put the bottom and side plates back together. Applied power and ground and then the 2 30 amp fuses blew on the side of the amp. Check for continuity between B+ and ground and got 0.6 ohms. Then I took the amp apart again and checked. I am right back to where I started from. That 3205 is bad now and maybe more. I really don’t have a clue why this happened. Any Ideas?
Thanks,
Sean
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