Memphis 16-MCD1000 burnt gate resistors

Justinh722 · 14th September 2011, 03:06 AM

A friend of mine has this amp which would power on and go into protect. I opened it up and found the gate resistors to be severely burnt. I tested them with an ohm meter and got 31 ohms on both. The Board had burnt so bad that the traces are completely gone on the one side of the resistors. I removed them and cleaned up the board but I can't find what trace they went to. The other side of the resistors go to a set of 4 diodes.

I don't understand how the board could have melted but yet the resistors are still good. Does the other side of the resistors go to a 12 volt pad on the board? I'm not having any luck finding a schematic for the amp. Here's a pic I took that didn't turn out the best but shows the burnt board.

nigelwright7557 · 14th September 2011, 08:11 PM

I would guess the output mosfets have gone drawing a lot of current through the gate resistors.

Justinh722 · 16th September 2011, 08:10 AM

I know the fets would be easily replaced, but how would I go about replacing the traces to the gate resistors?

Justinh722 · 17th September 2011, 03:45 PM

The guy I got the amp from has another one of these and let me open it up. I took a pic and verified that the gate resistors each go to a diode on one side but the other side I couldn't see what trace they ran to because it was on the bottom of the board.

The amp I have still has the diode traces intact that lead to the resistors. Where do the gate resistors go to before they go to the diodes? I see the trace under C50 and C51 says LED GND. If I remember right, I tested voltage on that trace and it read 12 volts. Anyone know? I appreciate the help.

nigelwright7557 · 17th September 2011, 10:20 PM

The easiest way to fix fried traces is with wire links.
Scrape off the solder resist, tin the track and solder your wires to that.

Justinh722 · 18th September 2011, 02:04 AM

Yea I know how to repair a trace. I was just wondering if someone knew how I can find out what trace the resistors go to. What component goes to the resistors and then to the diodes? The board is literally melted on the amp right where it says C51.

It has no trace, just the inside of the board showing through and the 2 holes for the resistors. Does someone else have this amp or resources to a schematic? Maybe someone has come across pics of the board? Appreciate the help

leester18 · 26th September 2011, 02:13 PM

i have the same problem with my amp but my board is not melted and my amp will turn on and some what play but you can tell it has fried resisters and diodes. i have called memphis and they wont release the schematic because they still repair these amps

14th September 2011, 03:06 AM	#1
Justinh722 diyAudio Member Join Date: Sep 2009 Location: Iowa	Memphis 16-MCD1000 burnt gate resistors A friend of mine has this amp which would power on and go into protect. I opened it up and found the gate resistors to be severely burnt. I tested them with an ohm meter and got 31 ohms on both. The Board had burnt so bad that the traces are completely gone on the one side of the resistors. I removed them and cleaned up the board but I can't find what trace they went to. The other side of the resistors go to a set of 4 diodes. I don't understand how the board could have melted but yet the resistors are still good. Does the other side of the resistors go to a 12 volt pad on the board? I'm not having any luck finding a schematic for the amp. Here's a pic I took that didn't turn out the best but shows the burnt board.

14th September 2011, 08:11 PM	#2
nigelwright7557 diyAudio Member Join Date: Apr 2008 Location: Carlisle, England	I would guess the output mosfets have gone drawing a lot of current through the gate resistors. __________________ http://www.murtonpikesystems.co.uk PCBCAD40 pcb design software.

17th September 2011, 10:20 PM	#5
nigelwright7557 diyAudio Member Join Date: Apr 2008 Location: Carlisle, England	The easiest way to fix fried traces is with wire links. Scrape off the solder resist, tin the track and solder your wires to that. __________________ http://www.murtonpikesystems.co.uk PCBCAD40 pcb design software.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
MTX JH600 w/burnt gate resistors	Ronode	Car Audio	2	2nd August 2011 06:38 PM
Memphis 16-mcd1000	bdgf2004	Car Audio	17	9th May 2011 05:47 AM
Memphis 16-MCD1000 output filter capacitors	Ronode	Car Audio	1	23rd March 2011 04:54 PM
Memphis 16-mc1000d	mike49504	Car Audio	46	9th July 2010 09:06 PM
memphis 16-ST500D	frt96	Car Audio	2	9th May 2008 07:16 AM


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

16th September 2011, 08:10 AM	#3
Justinh722 diyAudio Member Join Date: Sep 2009 Location: Iowa	I know the fets would be easily replaced, but how would I go about replacing the traces to the gate resistors?

17th September 2011, 03:45 PM	#4
Justinh722 diyAudio Member Join Date: Sep 2009 Location: Iowa	The guy I got the amp from has another one of these and let me open it up. I took a pic and verified that the gate resistors each go to a diode on one side but the other side I couldn't see what trace they ran to because it was on the bottom of the board. The amp I have still has the diode traces intact that lead to the resistors. Where do the gate resistors go to before they go to the diodes? I see the trace under C50 and C51 says LED GND. If I remember right, I tested voltage on that trace and it read 12 volts. Anyone know? I appreciate the help.

18th September 2011, 02:04 AM	#6
Justinh722 diyAudio Member Join Date: Sep 2009 Location: Iowa	Yea I know how to repair a trace. I was just wondering if someone knew how I can find out what trace the resistors go to. What component goes to the resistors and then to the diodes? The board is literally melted on the amp right where it says C51. It has no trace, just the inside of the board showing through and the 2 holes for the resistors. Does someone else have this amp or resources to a schematic? Maybe someone has come across pics of the board? Appreciate the help

26th September 2011, 02:13 PM	#7
leester18 diyAudio Member Join Date: Sep 2011	i have the same problem with my amp but my board is not melted and my amp will turn on and some what play but you can tell it has fried resisters and diodes. i have called memphis and they wont release the schematic because they still repair these amps

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read