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owlmeat

1990s 12.5 LTH Electrical Issue

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owlmeat
First off, thank you all for hosting and contributing to such an informative website. I'm glad to be a new member. Ive got a Model 1691886 LTH from the early 90s. Its a great mower and Ive had few problems with it. Recently I was checking the amp draw on the PTO clutch to verify it was within spec. Well, I accidentally dropped the jumper wire I was using and it touched the frame for a moment. The mower immediately turned off. Now the mower will not start with the key. However, I can still start it across the solenoid terminals manually. It fires and runs fine. However, as soon as I take it out of neutral, the neutral switch kills the engine. Here is what I have done: 1) I ohmed the ignition switch, the PTO switch, the seat kill switch, and the neutral switch and all terminals are behaving as they should. 2) When checking the solenoid (4 terminal), I am getting 4 to 6 ohms across the relay terminals. This sounds to me like a partially shorted solenoid. (to me at least) 3) The leads going to the solenoid BOTH read positive voltage. 12v on what I consider the positive lead and 4.3V on what I consider the ground lead. BTW, I also checked ohms across the ground lead to ground, it was an open loop. 4) I tracked the 4.3V offending voltage across the neutral interlock switch, across the PTO switch and back to the mysterious "module" Simplicity part number 1703972, made by marlintech.com. By the time I get to the module, the voltage is reading 12v at the module terminal. 5) Im thinking "yep I need a new module and solenoid." So I go buy both. I installed the solenoid, checked the tractor, same results. I then installed the new module, same results. I check the resistance across the relay terminals of the solenoid and guess what? 6ohms. Did my bad module break my new solenoid, then my new bad solenoid break my new module? Anyway, I cant seem to find any info on the "module", so I cant troubleshoot past it. The tractor still runs fine if I jumper across the solenoids starting terminals. Still dies if I try to take it out of neutral. Am I missing something? (I'm very close to throwing this "module" down my driveway and rewiring the tractor myself without it... but I figure that is the wrong way to tackle this problem. Any experiences, thoughts, or ramblings you have on it would be much appreciated! (sorry for the long post, tried to be thorough) Roy (owlmeat)

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