Problem with Kicker Kx 500.2 Amp

[Perry Babin]

Replace all of them, clamp all components tightly to the heatsink and insert a 10-15 amp fuse in the B+ line before applying power.

You need to insert some sort of insulator between the clip-on heatsinks or otherwise make sure that they cannot make contact. Apply heatsink compound between the clip-on sinks and the transistors.

[tireman406]

All parts installed.

+15 v has .860
-15 v has -1.30

Rechecked all solders and they are good. Tried a sound test and nothing.
Any suggestions?

[Perry Babin]

Did you install the 6488 and 6491 as shown in the photo?

[Perry Babin]

Did you install the 6488 and 6491 as shown in the photo?

Q15 is the 6488.

[tireman406]

Confirmed Q15 is the 6488. They are installed exactly like picture other than I have yet to install the headsink. I wanted to verify sound before installing. The ones that came out had part numbers facing me with the power supply on my left. I installed the new ones the exact same way.

[Perry Babin]

Are you sure that you have them as shown in the photo? In the photo, you can see the preamp board in the lower left corner. The fronts of the transistors are facing the right side of the photo.

[tireman406]

I couldn't see the fronts in the picture. So with that said I believe I have them in flipped the wrong way. I put them in the same way the old came out. Would putting them in backwards fry them?
I will switch them around and see what happens.

[Desafinado]

Not to hijack but my amp went to inoperative and was for the voltage regulators. I did what Mr Babin said but be absolutely sure that the solder in the B649 is good. I was having erratic -15v readings and rechecked everything with no luck, so i desoldered my mod (as you can see in my thread, i put the voltage regulators directly to the heatsink), removed all the old solder, resolded them and reinstalled everything and the amp was working as normal. Note that i reused the old parts because where i live i never found replacements for b649,i would like to do that in the future.

I have learned from this amp a lot!

[tireman406]

Status update. Got Q15 & Q16 turned around and installed heat sinks. Powered up amp had proper voltage at +/-15 volt pins. Hooked speaker to amp with audio input through RCA connection. Worked like a champ. Thank you again Perry for all of your help. I will remember you if I ever have amp problems in the future.

Will let you know how it works when reinstalled in vehicle and hooked to subwoofers.

[Desafinado]

Be sure to reinstall properly the amp when you are going to wire with the woofers. I did not install mine properly (loose conection in the B+) and the fuses got melted. My amp is still working right now, i had mine powering two CVR´s 12" 8 ohm each, bridged. Sounds very good.

Glad that everything works now.