Accidently Reversed booster cables, now starter engages when key is in 'run' position

helomech

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
Could not see any voltage on what I believe to be the 'trigger wire' (blue). That one eems to be grounded (or a continuity close to ground). By a piggy back solenoid, I assume you mean it's physically attached to the starter? If so, yes it is.

I've attached a wiring diagram.

If there is no voltage on the blue wire, that means the key is not the problem. Power has to be flowing through the relay to get to that starter.
 

helomech

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
Yes that's right. When I turn the key to the 'run' position, I hear the solenoid click to engage the starter. Pretty sure that's only supposed to happen when I turn the key to the 'start' position, not 'run'. When key is off, there is no continuity across the two large terminals at the solenoid so it does appear to be 'stuck' on.

Sounds to me, like the solenoid/relay is burned closed.
 

meteors63

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
But if it was burned closed, I should read a closed circuit when I put the VOM across the main posts, shouldn't I? But it shows an open circuit while the key is off. I can hear the clunk of the relay when I turn on the key (just as it starts cranking). Or am I out to lunch on this? I'm no mechanic so maybe I'm missing the point. Sorry about that.
 

mechanic mark

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
But if it was burned closed, I should read a closed circuit when I put the VOM across the main posts, shouldn't I? But it shows an open circuit while the key is off. I can hear the clunk of the relay when I turn on the key (just as it starts cranking). Or am I out to lunch on this? I'm no mechanic so maybe I'm missing the point. Sorry about that.

do not remove starter or anything else, be patient & let Rivets weigh in, bertsmobile 1 & ILENGINE, are all very knowledgeable Men!


do not pull engine, let Rivets weigh in on this one, he is a retired instructor, very knowledgeable troubleshooter. i'll send him a message regarding issue.

message sent!
 
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meteors63

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
OK thanks Mark!
 

mechanic mark

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
OK thanks Mark!

your quite welcome meteors63, hopefully Rivets will reply soon, he is a retired instructor & works for a Toro dealer in Wisconsin!
 

helomech

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
But if it was burned closed, I should read a closed circuit when I put the VOM across the main posts, shouldn't I? But it shows an open circuit while the key is off. I can hear the clunk of the relay when I turn on the key (just as it starts cranking). Or am I out to lunch on this? I'm no mechanic so maybe I'm missing the point. Sorry about that.

Yes, but the power is coming from somewhere. The blue wire has to have power if the relay is pulling. There are only 2 sources of power going to this relay correct? From the battery, then from the switch. Maybe the key is fried, disconnect and check the blue for continuity with the key in the run position.

I agree with mark, don't pull the engine. the starter is working, something is telling it to turn on.
 

bertsmobile1

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
pull the key switch out and then pull the wiring plug through the hole so you can get to the wires.
To start the key switch connects the B = Battery wire to the S = Start wire.
'The letters are on the back of the switch.
To run the key switch should disconnect the S wire ( blue wire )
If the S is still connected to the B with the switch in run position then the switch is faulty

NExt you replace the switch with patch leads
Connect the B to the A & L terminals on the plug with the switch removed.
If the starter cranks then you have a problem in the wiring.
 

meteors63

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
I bought a new ignition switch (key) but apparently I didn't need to. I tested both switches and they both work exactly the same (as as they should be working). But I have no "A" on m my key switches. Only G, B, M, L and S. In the OFF position, G and M or connected. In RUN, B and L or connected, and on the spring loaded START position, L, B, and S or connected. From what I've researched, that's the way they're supposed to work too. Hopefully this is right and I don't have TWO bad key switches.

I'm uploading a video of some of the things I've observed. Will post it as soon as I'm able to. Thanks guys.
 

bertsmobile1

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  • / Accidently Reversed booster cables, now starter engages when key is in 'run' position
SO as you know how the switch connects the wires, make the connections at the plug as per my previous post.
If the engine cranks with just the B & L connected then you have a short between the blue wire and a power wire.
There are 5/8 of SFA power wires on a mower, most circuits are ground circuits.
So it should not be hard to trace the wire back in the loom.
 
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