Safety switch problem on Husqvarna Z248F zero-turn mower

Loose_Screws

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I have a problem with a Husqvarna Z248F zero-turn mower. It's a 2015 model. When I move the steering levers inward with the seat occupied, the motor stops. It seems logical that the problem is probably with the safety switch under the seat. I've removed the seat switch and by using a c-clamp, I am able to depress the switch to close the electric circuit and keep it closed while I move the steering levers inward. The motor still stops after doing that with the seat sensor circuit closed. Can someone suggest where I should look next to fix this problem? BTW, I put a piece of PVC pipe between the steering levers so I can start the motor and keep it running while the seat is not occupied. I have the electric wiring schematic for this mower but it is the worst schematic I have ever seen and of little help. May I hear your suggestions and comments, please. Thank you.
 

Bertrrr

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There are safety switches on each of the leavers you mentioned
 

StarTech

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Don't forget the seat switch connector has a shorting strip that activates when the connector is loose. It also can become damage and still short out the connector. Also seat must be tested electrically not just mechanically. The switch and the lap bars switch are double pole switch with the none depress position being a normal closed switch contacts on both poles.
 

Loose_Screws

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Don't forget the seat switch connector has a shorting strip that activates when the connector is loose. It also can become damage and still short out the connector. Also seat must be tested electrically not just mechanically. The switch and the lap bars switch are double pole switch with the none depress position being a normal closed switch contacts on both poles.
StarTech, can you please tell me more about this "shorting strip?" Is that the same thing as a shorting block? Thanks.
 
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StarTech

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In the seat switch connector they installed this strip. Most time is for both poles of the switch, othertime a two prone version is use. But full version looks like this.
1732204438093.png
What I call fingers of the strip get bent and they continue shorting as lifting tabs on the switch just can't lift them the contacts(pins) of the switch assy. Back probe the connector using a continuity (ohm) meter while the connector is attached to the switch and the switch is depress and if these are working as intended then you get an open circuit reading. Otherwise you get a closed circuit reading.

If these are not working as intended simply remove the strip since the connector is not available except as part of the complete harness. Needle Nos pliers usually does the trick.

Personally I would rather replace the connector but I have yet to find a source just for it.

EDIT> I better post the switch details too.
1732205161715.png
 

Loose_Screws

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In the seat switch connector they installed this strip. Most time is for both poles of the switch, othertime a two prone version is use. But full version looks like this.
View attachment 70140
What I call fingers of the strip get bent and they continue shorting as lifting tabs on the switch just can't lift them the contacts(pins) of the switch assy. Back probe the connector using a continuity (ohm) meter while the connector is attached to the switch and the switch is depress and if these are working as intended then you get an open circuit reading. Otherwise you get a closed circuit reading.

If these are not working as intended simply remove the strip since the connector is not available except as part of the complete harness. Needle Nos pliers usually does the trick.

Personally I would rather replace the connector but I have yet to find a source just for it.

EDIT> I better post the switch details too.
View attachment 70141
I can't do it now, but later I will look at the seat safety switch connector again. It would be great if this is where the problem is. Husqvarna's wiring schematic is so poorly done, I can't make much use of it. It would be nice to be able to put my fingers physically on each wire coming out of that connector and examine the connections end to end. I'd run some temporary jumper wires around the connector if I could better understand the schematic.

Husqvarna Z248F Electrical Wiring Schematic.jpg
 

Loose_Screws

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I just figured out the schematic. The black wire going into the connector is the power supply. The blue wire coming out of the connector goes to the left steering lever. If I'm going to bypass the seat safety plunger switch temporarily, I'll want to run a jumper wire from the black wire to the blue wire. If after doing that, the motor no longer stops when I move the left steering lever inward, then I've proven there is a faulty connection in the connector or the seat safety plunger switch.
 
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StarTech

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One problem. Jumping the switches that are NC (normal closed) would the same as you have not activated them or basically you are shorting to ground

And BTW the Black wire is the ground circuit and not the 12V positive circuit.
 
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