Hey all, I'm a new member to the forum, been wanting to join for a while and I finally got around to it, haha. I was wondering if you guys could help me out with a little dilemma. So I just picked up a Yamaha SJ550HR, incredible guitar, same pickups Carlos Santana used in the '70s. Everything works fine. Except when the bridge pickup is selected. The bridge should sound like a really good Les Paul, it has a bit of a PAF feel (except with more sensitivity), yet when I select the bridge, it sounds incredibly thin and weak, as if it were stuck on coil split (the coil split is a common problem on these). So I investigated with the ohmeter in the electronics panel.
First off, the neck pickup works perfectly. Splits perfectly, goes back to humbucker mode, resistance doesn't change even when the bridge is selected, flawless.
When the neck pickup is selected, the bridge pickup measures 13k ohms, which is what it should be, so I think we can rule out the pickup itself. With the neck pickup selected, the bridge also splits correctly at the split pot and reverts back to its original resistance, so I think we can rule out the coil split.
But when I select the bridge pickup, everything changes. At the switch, it measures about 3k. At the coil split pot, it measures 3k whether the split is activated or not.
So the problem is obviously at the switch, correct? Now, is the bridge pickup just wired incorrectly at the switch, or is the switch itself (which is what I suspect) defective? All the solder joints are pretty solid, and as far as I can see (I'll check again later) there are no bare wires making contact anywhere, everything is covered and neat.
The electronics layout is this: dual humbuckers, volume pot X1, tone pot/coil split X1, 3-way selector switch. I only checked the selector switch and tone pot, everything else seems above suspicion.
Again, I'm new to the forum, and I'd greatly appreciate any help I can get, thanks.
P.S. There's a crackling sound when I switch from the neck to the middle to the bridge, I'm just gonna assume it's the switch.
Also have no idea why no one's replying... I get that I'm the new guy, but everyone else seems to have their threads answered within the hour, anyways I'd really appreciate it if anyone could confirm my suspicions of the pickup switch.
First off, the neck pickup works perfectly. Splits perfectly, goes back to humbucker mode, resistance doesn't change even when the bridge is selected, flawless.
When the neck pickup is selected, the bridge pickup measures 13k ohms, which is what it should be, so I think we can rule out the pickup itself. With the neck pickup selected, the bridge also splits correctly at the split pot and reverts back to its original resistance, so I think we can rule out the coil split.
But when I select the bridge pickup, everything changes. At the switch, it measures about 3k. At the coil split pot, it measures 3k whether the split is activated or not.
So the problem is obviously at the switch, correct? Now, is the bridge pickup just wired incorrectly at the switch, or is the switch itself (which is what I suspect) defective? All the solder joints are pretty solid, and as far as I can see (I'll check again later) there are no bare wires making contact anywhere, everything is covered and neat.
The electronics layout is this: dual humbuckers, volume pot X1, tone pot/coil split X1, 3-way selector switch. I only checked the selector switch and tone pot, everything else seems above suspicion.
Again, I'm new to the forum, and I'd greatly appreciate any help I can get, thanks.
P.S. There's a crackling sound when I switch from the neck to the middle to the bridge, I'm just gonna assume it's the switch.
Also have no idea why no one's replying... I get that I'm the new guy, but everyone else seems to have their threads answered within the hour, anyways I'd really appreciate it if anyone could confirm my suspicions of the pickup switch.
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