Guitar Gear Forum

The toggle broke off the power switch for my '81 JMP (Canadian version).

I thought it was going to be a straightforward fix but, in my typical fashion, I've screwed something up.

The power light isn't turning on.

The old switch assembly had a blue and brown wire tied to each side of the switch (they weren't soldered but were attached by tightening the screws.)




I bought a new switch rated for the same specs as the old one -- 15a 125 vac, 10a 250 vac -- with four lugs.



I took the blue top right wire from the old one and soldered it to the top right lug of the new switch. I then took the brown bottom right from the old switch and soldered it to the bottom right lug of the new switch.

I then did the same thing for the other side of the switch.



I though the lugs on the new switch would be the same as the old one.

When I turn on the new power switch, the power light doesn't light up.

Any ideas? Did I mix up the lugs?

Just curious... if the original switch had 1 brown and 1 blue wire, how did you wind up with 2 brown and 2 blue wires?

I'm guessing but, maybe you only needed to hook 1 blue wire to the top right lug and the 1 brown wire to the bottom right lug?

The first step would be to use your multimeter set to ohms or continuity test to check the new switch. Verify that it works.

Also, be careful in there. Don't assume it's not on just because the light doesn't come on. Those little lights can blow.

If the switch is good and properly wired, next thing to check is fuses. Check those with your meter also. Fuses can look ok but be bad.

Just measured the switch. I did indeed have it wired incorrectly. I need to switch the blue wires to one side, brown on the other.

Now I just need to find a 3.15a 250v SB ceramic fuse. My local supplier doesn't have them.

Axe wrote:Just measured the switch. I did indeed have it wired incorrectly. I need to switch the blue wires to one side, brown on the other.

Now I just need to find a 3.15a 250v SB ceramic fuse. My local supplier doesn't have them.

Sounds like you're on the right track.

It sucks not to be able to get things locally. You can't even get guitar strings here on Sunday.

All wired and fused up. The JMP lives to rock another day.