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Can someone help me decipher all this?







I'm a little salty about the jazzmaster I've got, as it was a made to order and finished around the time the American Pro II line started getting publicity. I really like the wiring setup they've got going on with them, but I'm having trouble figuring it all out in order to replicate it in my guitar. I typically reference fender service manuals, but I haven't found one posted for these yet.

For reference, the "rhythm" circuit has now become an in series circuit. It looks like it uses a 4PDT two way slider switch, and I assume the pots are both 1 meg.

The tone pot is a push/push that makes the bridge pickup have more body and output. I'm not 100% sure what's going on with that circuit either.

I know they used 500k pots for the lead circuit on the AmPro 1st gens, and I'm not sure if they went back to the 1 megs or if they stuck with 500ks.

Any help would be appreciated.

The parts/wiring manual usually drops several months after the guitar is released. The last complex-circuited JM was the Ultra. Its wiring was traced by a member here who had access to an Ultra, before the manual came out. With the Am Pro II JM adding circuitry for which there is no real precedent - series rhythm circuit with roller volume and tone pots, plus the bridge coil tap - an early wiring diagram would probably similarly require someone to have the guitar in their hands so that they could trace it out. The pics alone are too hard to do that with. Do you have access to the actual guitar or just the wiring pics ?

I can totally understand that. These are some of the only pictures I've been able to find that actually shows the loaded pickguard off of the body with close ups of the wiring. I found this on a Reverb listing, and it's the best I've been able to find so far.

Bumping this thread, would like to wire my JM build similarly, maybe now more people have the Am Pro II that are willing to trace the wiring for the rest of us, I haven’t found a service manual for it as of yet.

gibs wrote: ↑

Sat Jul 24, 2021 12:18 pm

Bumping this thread, would like to wire my JM build similarly, maybe now more people have the Am Pro II that are willing to trace the wiring for the rest of us, I haven’t found a service manual for it as of yet.

I've been watching for the service manual for what seems like months now. For some reason Fender has not posted them for any of the Am Pro II series yet (strat, tele, JM). Strange times for sure, but they're really late.

Here is a messy drawing. The lead pots are both 500K, while the upper circuit are both 1MEG. Both caps are 223k (0.022uf).



The blue wire on the bridge pickup is the mid-coil tap, so with the switch in the innie position blue is disconnected from the circuit and you get the full ~11.35k (black to yellow), with the switch in the outtie position the yellow is disconnected and you're only getting 7.35k (black to blue).

tammyw wrote: ↑

Wed Jul 28, 2021 3:40 pm

Here is a messy drawing. The lead pots are both 500K, while the upper circuit are both 1MEG. Both caps are 223k (0.022uf).



The blue wire on the bridge pickup is the mid-coil tap, so with the switch in the innie position blue is disconnected from the circuit and you get the full ~11.35k (black to yellow), with the switch in the outtie position the yellow is disconnected and you're only getting 7.35k (black to blue).

Awesome, thank you so much!

Great explanation and scheme, thanks. I was wondering what is going on with the wiring (blue wire). Makes me wonder how to change the bridge pickup to some aftermarket ones, since now Fender has added the "mid-coil tap" as a third wire? Or do you just lose the push-pull -functionality / rewire to get the full output on both positions?

mauri wrote: ↑

Tue Aug 03, 2021 11:39 am

Great explanation and scheme, thanks. I was wondering what is going on with the wiring (blue wire). Makes me wonder how to change the bridge pickup to some aftermarket ones, since now Fender has added the "mid-coil tap" as a third wire? Or do you just lose the push-pull -functionality / rewire to get the full output on both positions?

Could repurpose as a mute/kill switch. Up position mutes your signal, and the down position activates the electronics.

The official service manual/wiring diagram has finally dropped from Fender:
https://www.fmicassets.com/Damroot/Orig ... master.pdf

In the Fender diagram, on the tone pot push-push switch they've mixed up the blue and yellow wires from the bridge pickup. The blue wire should be on the pin closest to the pot body.

tammyw wrote: ↑

Wed Aug 04, 2021 5:11 am

In the Fender diagram, on the tone pot push-push switch they've mixed up the blue and yellow wires from the bridge pickup. The blue wire should be on the pin closest to the pot body.

Strangely, they got it right on the switch in left hand version !
https://www.fmicassets.com/Damroot/Orig ... ter_LH.pdf

gibs wrote: ↑

Tue Aug 03, 2021 12:02 pm

Could repurpose as a mute/kill switch. Up position mutes your signal, and the down position activates the electronics.

I was thinking the same, but it would only affect on the bridge -pickup. I'm thinking of replacing the tone knob with the traditional knob if the wiring isn't too complicated to rework. Ofcourse I could just leave it as it is and the other position just doesn't work. I don't find that much use for the push-push anyways, atleast for so far.

mauri wrote: ↑

Thu Aug 05, 2021 5:05 am

gibs wrote: ↑

Tue Aug 03, 2021 12:02 pm

Could repurpose as a mute/kill switch. Up position mutes your signal, and the down position activates the electronics.

I was thinking the same, but it would only affect on the bridge -pickup. I'm thinking of replacing the tone knob with the traditional knob if the wiring isn't too complicated to rework. Ofcourse I could just leave it as it is and the other position just doesn't work. I don't find that much use for the push-push anyways, atleast for so far.

If you take the line from the center lug of the 4pdt switch running to the jack tip, and run it first to the push/push switch, then one side of the switch to ground and the other side to the output jack, it would then mute both pickups.

gibs wrote: ↑

Thu Aug 05, 2021 6:53 am

If you take the line from the center lug of the 4pdt switch running to the jack tip, and run it first to the push/push switch, then one side of the switch to ground and the other side to the output jack, it would then mute both pickups.

Thanks, nice to know it could be done. I almost understand what needs to be wired, but still not enough without a diagram So maybe I'll just try the pups and see how it goes. Starting to get regrets with Antiquity ones, maybe I should have gone with 2 instead..