PDA

View Full Version : PRS McCarty Wiring Problem


dk_ace
05-29-2012, 10:46 PM
I did some work on my McCarty over the weekend. One of the things I did was put the stock pickups and wiring back in (changed them several years ago to try something new).

Everything is working as it should except for the bridge pickup coil split. The push/pull tone pot that splits the coils works fine for the neck pickup, but it does nothing for the bridge. I've checked the wiring diagram a dozen times and my connections a dozen times. I can't see anything wrong, but it doesn't work on the bridge. Even though the joints looked good, I re-did the relevant solder joints to see if I might have had a cold joint somewhere. That wasn't the case though as I still have the problem.

I still have signal, but the pickup remains in humbucker mode. When in the middle pickup selector position while the tone pot is pulled out, I have the neck pickup in split mode and the bridge in humbucker mode.

I'm not a guitar wiring afficianado by any stretch. I've done a few succesfully, but generally there are a few mistakes I have to go track down after the first try. This guitar was no different, and I've corrected the few other issues I had but I just can't find why this isn't working.

Anyone have an idea of what to look for?

I'm wiring it this way (current diagram):

http://www.prsguitars.com/csc/schematics/schem08/mccarty.pdf

D

Clorenzo
05-30-2012, 03:12 AM
If you're positive the wiring is as it should, something is not closing the circuit between the bridge pu white wire and ground: either the push / pull got fried from soldering - desoldering, or the wire was pulled and came loose on the pickup side, or even broken somewhere in the middle. Easy to test: just short those two lugs of the p/p, where the bridge white and ground go, with a screwdriver and see if that splits the pu. If it does, it's the p/p (replace); if it doesn't, it's the wire (open the pu and see if you can re-attach / replace the wire).

dk_ace
05-30-2012, 09:57 AM
If you're positive the wiring is as it should, something is not closing the circuit between the bridge pu white wire and ground: either the push / pull got fried from soldering - desoldering, or the wire was pulled and came loose on the pickup side, or even broken somewhere in the middle. Easy to test: just short those two lugs of the p/p, where the bridge white and ground go, with a screwdriver and see if that splits the pu. If it does, it's the p/p (replace); if it doesn't, it's the wire (open the pu and see if you can re-attach / replace the wire).

Awesome, thank you! I will test it later and report back. I'm not familiar enough with this stuff to know how to troubleshoot it properly. I wondered if it might be the switch or the white wire but didn't know how to test it. Both problems are possible. The switch might have endured some abuse at my hands due to a wiring mod I unsuccessfully tried a few years back. This test should sort it for me though. I'll look over the wiring again but I'm almost 100% certain all the connections are made well and in the appropriate place.

D

dk_ace
05-31-2012, 08:22 AM
That screwdriver trick is exactly what I needed. I guess the heat got to me the other day when I did the wiring. I had the connections in the proper places, but when I was trying to troubleshoot the bridge pickup tap I was reading the diagram backwards and focusing my efforts on the connections that affect the neck pickup tap (which was already working). Playing with the screwdriver showed me that I was working on the wrong thing. I bent one of the posts back that I had bent slightly when wiring everything up and them resoldered the real bridge tap connections. Everything works and sounds great now, thanks!

D

blong
06-03-2012, 09:13 PM
I think PRS reverses the wire color on the two coils on their guitars. On one pickup the white is for one coil, the black for the other. On the other pup, they are reversed. If you switch those two wires it should work. Look up the wiring diagrams on PRS website. I will open mine up or look at the diagrams and post back so I can be of more help.

I wired Dragon II's into a Santana SE and was having the same problem til I looked up the wiring diagram and had them backwards for one pup. I flipped 'em and problem solved.

I hope this helps. I will check and post again in a bit.

Bob

blong
06-03-2012, 09:20 PM
I was mistaken in my recollection. I checked my notes from that job and I had the issue b/c I dropped an RSGuitarworks McCarty upgrade kit in. They wire their kit slightly differently, that's why my wiring was wrong. PRS does it one way, RS does it slightly differently. I don't think my last post was quite accurate for your issue, but it might be. Sounds like you figured it out.

Sorry if added any confusion. I reread your last post and realize you fixed your problem.

Bob

walterw
06-03-2012, 09:48 PM
prs does indeed reverse the wire colors for their neck and bridge pickups (can't recall how just now, but if you wire them both with the same colors as hot, ground and coil-split to ground, you won't get what you want).

johnmfer
06-04-2012, 02:08 PM
The PRS wire color issue you're talking about only applies to pickups that are also compatible with their 5 way rotary. The McCarty pickups he's working with are not compatible and have a vintage style braided wire for the main humbucker, with a completely separate smaller white wire for coil splitting.