Kenwood KAC-7005PS Problem

[Frycztech]

I don't know where you're located so I can't recommend electronics distributors.

The IRFB31N20D is obsolete. Any you find may be counterfeit. The IRF640 or IRF640N may be a suitable replacement. You must replace both the defective FET and the one that was parallel with it.

Does the sub channel now produce audio?

Ok. I didn't play music through it because i had things not fully clamped down. Should I?

 

[Perry Babin]

You need to know whether the shorted output was the only problem or if there are other problems. Clamp everything down and check for audio.

 

[Frycztech]

I don't know where you're located so I can't recommend electronics distributors.

The IRFB31N20D is obsolete. Any you find may be counterfeit. The IRF640 or IRF640N may be a suitable replacement. You must replace both the defective FET and the one that was parallel with it.

Does the sub channel now produce audio?

I would be buying offline usually I use Mouser.

I connected everything and iam getting a pulsing coming out of the sub channel even if no music is being played.

 

[Perry Babin]

Are the gate resistors for the output transistors within tolerance?

Check the driver transistors for the output transistors and all resistors between the drivers and the output transistors.

 

[Frycztech]

So the gate resistors would be R320, R318, R319, R317?

They all read about 10.2ohms

 

[Perry Babin]

Were all of the drivers and resistors in that area OK?

 

[Frycztech]

Iam I looking just by the bad FET that I removed? I don't see anything else besides the resistors I checked.

 

[Perry Babin]

Check the transistors highlighted below. Check the initially in the board and if you find any that look bad, pull them and re-check.