Hifonics brutus bx1500d

[mike49504]

When trying to power this amp up it draws 40+ amps of current. I took the outputs out of the amp and tryed it again still draws 40+ amps.

I checked the fets all test good but looks like someone messed with them .

The fets that are in this amp right now are FQP65N06 with 100 ohm gate resistors.

Wondering what to check next since this thing is drawing way to much current

 

[Perry Babin]

While powering it up through a limiting resistor, try twisting/pushing/pulling on the transformer to see if the current draw changes.

Does it only draw excessive current after applying remote voltage?

Is it possible that the FETs were replaced? If so, check the driver transistors and the gate resistors.

 

[mike49504]

It only draws 40+ amps when remote is hooked up .
Tryed powering it up with a current limiting resistor and twisting pulling on the transformers nothing changes.

Its possible they were switched (fets) looks like new solder on all of the fets.

checked all gate resistors all check fine also checked the drivers a1266 they also check fine but dont have any to stick in there to see if one is leaking

Also i found a diode in the output side thats bad it says P6KE68A wondering what i can replace it with.

and i think the guy said he smoked one of the IC'S but he didnt know which one

wondering where i go from here

 

[Perry Babin]

The P6KE68A is used to protect the 4080 from over-voltage. You need to replace it with the same part.

Pull the 4080 and power up the amp. Does it still draw excessive current?

If so, pull the rectifiers to see if the excessive current draw remains.

You can check the driver transistors to determine if they're leaking, shorted, open or OK.

 

[mike49504]

ok with the 4080 removed it powers up fine doesnt draw excessive current.

 

[mike49504]

the outputs in this amp 2 are blown also they read ir 425h wondering what the part number is??

 

[Perry Babin]

There should be other numbers also. Wipe some of the heatsink compound onto the face of the transistor and then wipe off as much as possible. That should make it easier to read the numbers.

 

[mike49504]

all the numbers on the fet read 94-2355 I R 425H fc 3a

 

[Perry Babin]

From what I found via google, they are likely IRF3710s.

 

[mike49504]

ok replaced the hip4080 and the diode with no outputs in the amp it idles around 15 amp with the hip 4080 removed it idles at 2 amps wondering what to check next

 

[Perry Babin]

Are you saying that all of the transistors marked 94-2355 have been removed and there are no transistors in those locations?

 

[mike49504]

yes all have been removed bvecause the amp still draws current with them in or out

 

[Perry Babin]

Are you sure that you soldered the diodes back on the IC correctly?

Are you sure the IC was installed properly in the socket (not reversed)?

Did the new 4080 get hot?

 

[mike49504]

positive i put the 4080 in the right way also put the diode in correctly 4080 doesnt get hot.

Well i powerd it back uop again in the sink fets clamped tightly i see a 5w 33ohm sandstone resistor thats buldged in the back

 

[Perry Babin]

It would be unusual for that type of resistor to bulge without significant discoloration. Is it cracked with the area around the fracture darkened?

 

[mike49504]

didnt appear to be craked ui just replaced it anyway. I checked the other diodes connected to the 4080 diode fr105 is the number on it and it reads 4.76 the other larger pk diode reads 5.67

 

[mike49504]

ok this amp has 12 fets in the power supply if all 12 are in the amp idles at 15 amps if u take all of them out besides 2 (1 per side) the amp idles perfect wondering if i might have a power supply problem going on

 

[Perry Babin]

4.7v/5.67 ohms, volts, amp on/off...?

With only 1 FET/side, the power supply can't produce full rail voltage (because the transformers are not being driven properly - assuming that this amp has two transformers) which may be why it's not drawing excessive current. Reinstall all of them and clamp them down.

Remove the 4080 and post the DC voltage on all 20 pins of the 4080.

4080
Pin 1:
Pin 2:
Pin 3:
Pin 4:
Pin 5:
Pin 6:
Pin 7:
Pin 8:
Pin 9:
Pin 10:
Pin 11:
Pin 12:
Pin 13:
Pin 14:
Pin 15:
Pin 16:
Pin 17:
Pin 18:
Pin 19:
Pin 20:

 

[raresvintea]

i try to repair an amp like that and at 12V it draws 15Amps!!!!

the audio part is working ok, all the transistors were changed with IRF3710, on the supply area i need to change probably the driver circuit KIA494(TL494). Also i changed the transistors with irfz48 and the gate resistors. What can cause suck a big consume? What i need to check/recheck???

The guy that put this question, how do you resolved this issue?

 

[Londik]

Hello, I have a problem with Hifonics Brutus BX1500D. I've also experienced the exact problem with similar amps using the HIP4080 IC (Starsound, ...).

The problem goes like this: With no/little load the amp works just fine. Idle current is ok, output signal is ok etc. But when the load is increased the output becomes distorted. Sine wave becomes like this:

An externally hosted image should be here but it was not working when we last tested it.

Nothing fails, no part gets overheated, no exessive current, just this distortion. I've tried replacing output FETs, HIP4080 but with no results. Any idea?