Typically, the engine killing when engaging the PTO or disengaging the brake is caused bt=y a bad or misadjusted seat switch.
Also, check to make sure the seat switch is plugged in.

I went to the simplicity website to see if there was a manual available and I couldn't get your machine to show up.
IF you can find it and post a link.......

Electric clutch should show "about" 3 OHMS.

Hey thanks Bill. I uploaded the electrical schematic for my machine. I think you may be on the right track about the seat switch. For the moment - I absolutely HAD to get my mowing done after two weeks of rain - I have bypassed the kill circuit by going straight to the magneto from the ignition switch. Funny thing, though. The only way the engine will crank from the ignition switch is if the seat is not only unoccupied but RAISED to allow access to the engine. My jackleg wiring is reversible so as soon as I get the grass back under control I will replace the seat switch as there certainly seems to be something screwy going on there. The open circuit reading at the clutch was likely because I didn't think to calibrate my ohmmeter before testing.
Thanks again, you are obviously quite experienced.

I can't read the schematic you posted. Just too small/low resolution for these old eyes.

It's very odd you have to raise the seat to crank.
I've never seen a mower where the seat switch had anything to do with cranking????

Hi Bill

The schematic is a .jpg file so maybe your photo or image software can blow it up.

I told you it was a puzzle! No doubt my creative wiring has something to do with it, but in any case there is definitely an anomaly there.

prangster
Your image is only 96 dpi, at 640x300, and appears to be a screen print of some online manual. There's not enough resolution, so by the time you blow that up to something reasonable, it's too blurry.

I'll post the obvious, but did you check the circuit breaker? .

Can't imagine why seat position would effect cranking, unless the wires to the seat switch are somehow impacted by the tilt mechanism.

It looks like there's a safety switch on the seat, the transmission (neutral), and on the pedal, all tied to ground. Those should be easy to check.

The seat switch tested OK, but I had the seat up when I tested it. Since it is behaving strangely and isn't expensive I have sent off for a new one. While tracing wires I noticed the fuel cutoff wire looked like it had been hot at some time so that will be another job the next time I have the shroud off. The circuit breaker checked OK. Sorry about the schematic. It's blurry full size, so I don't think I can improve it. This is the first time I've had a serious problem with the mower in 13 years of hard use. I'm pretty confident I'm close to the solution now.

By the way, thank you all for your comments. I have learned a lot and am again amazed at the generosity of folks who post on forums like this. You guys rock!

Prang, if you can find your way back to the site where you screen shot the image, why not simply post the website URL as a link in a post and we can then just click the link and view exactly what you screen shot?
Surely if you can do a screen shot you can copy and paste a URL.