KW and o-22 switch wiring question

The center rail hooked up to A and the outside rail hooked up to U is correct with the constant voltage, post D, to the plugs on the switches.  Swapping A & U won't really do any damage right away but every time you hit the horn lever it is trying to activate the horn/whistle through the switches too.  Hitting the direction button will power down the switches as well.

Also, if you are going full speed, there will be no power to the switches.

Somebody has wired the diode or rectifier in the KW backwards. Dollars to donuts somebody "upgraded" it following the Lionel published schematic and didn't test it before buttoning it up.

I have another KW. I will hook it up to see if that is the case. Thanks Rob.

That was it. Now the lights come on when I plug it in and the horn, not the bell, comes on when I activate the whistle. You're the man Rob.

I did buy the other KW at the Allentown train show from someone who refurbishes them. I guess he didn't test it before he buttoned it up.

The good one came from Hennings. I'll take the bad one to him to fix after the holiday rush.

@Lennyski posted:

I guess he didn't test it before he buttoned it up.

If he's going to continue doing these repairs, he should be aware that most of the Lionel schematics have the polarity of the rectifier illustrated backwards. It really didn't make any difference until 1972 with the introduction of the 8206 with the electronic whistle.