Small Engines (Lawn Mowers, etc.): Interlock Switch Troubleshooting, blade switch, jumper wire

Question
Hello - I have a Sears 21 hp riding lawnmower model 917-274032 with electronic blade engaging switch (PTO Switch). When you push in the brake it starts fine but when you let out the brake it dies. As long as you hold in the brake in runs. If you engage the electronic blade switch (called the PTO switch) the engine dies - even with the brake pushed in. This problem appears to be caused by either the brake interlock switch or the PTO switch. How do you test, troubleshoot or figure out which switch it is? Thank you.

Answer
dean
Temporally remove the brake switch lock out and install a jumper (get a small wire ) and strip the ends and insert the wires in the socket of the brake switch do that and try it again,leave the jumper in and continue to do the rest the same way.Now if it corrects the problem remove 1 jumper wire and insert the switch try it again.Just keep trying until you find the bad switch