JD 180 electrical issue

[bobsphotos]

I can get up from the seat while in gear and the motor does not shut off. I can also get off the tractor with the PTO engaged, snd the motor does not die. I have checked the seat switch and it seems fine.
Any ideas?
Thanks,
Bob W

 

[beenthere]

From your explanation, the seat switch does not "seem fine"... is this a new "to you" tractor?

 

[bobsphotos]

I have had it for 20 years.

 

[bobsphotos]

Maybe my testing of the switch is flawed. When I check accross the seat switch contacts in the not activated situation ( not in the seat), it shows continuity across the contacts. When I depress the plunger, it opens the contacts.

 

[davesl708]

When testing the safety switch the switch should be closed when you are seated and break the circuit when you get off to shut off the engine.
As beenthere stated, check the switch for damage or a broken spring. At 20yrs old it could be worn out.

 

[tomplum]

If the seat switch was the problem and the modes were strangely reversed- wouldn't the PTO die when he got on the seat? I'd have to look, but I think lots of these were normally closed switches. There isn't lots on these. The seat wiring makes its way through the PTO switch. Sans something being altered along the way, that would be a consideration. You could probably find a schematic online to help sort things out. I don't have a digital copy myself.

 

[beenthere]

When I try to understand, do you mean the seat switch has operated like this for 20 years? If not, what transpired between the time it worked to now that it does not work like it should (or did) ??

I put a jumper wire in the connector and leave the seat switch dangle.. you might try that to see what the results are (i.e. bypass the seat switch).

 

[bobsphotos]

I have had the tractor for well in excess of 20 years and it all worked as it was supposed to until last summer. Just digging into it now because I am not comfortable letting my wife use it to mow the lawn. I found a wiring diagram online and the seat switch tests as it is supposed to.
I just went out and unhooked the seat switch and the behavior is unchanged and I put a jumper across the seat switch connector, and the behavior is also unchanged. I am going to study the schematic and try to see what the seat switch talks to and go from there.

 

[beenthere]

it all worked as it was supposed to until last summer.

And you don't recall doing anything to the wiring or other things at or near that same time?

 

[bobsphotos]

No sir...
I believe that somehow the ignition system and the PTO see the seat switch as always "open", as if the driver is always seated.
Just my take on it.
Bob W

 

[bobsphotos]

Problem solved....
K7LN was spot on with suggestion #3, as the picture will show. The snap together connection had gotten very, very hot at some point in time. I cut out the bad area and reconnected the wires and it works as it should.
Thanks all.
Bob W

 

[Richard001]

Yep,

Connectors are wiring's downfall. I worked for meany years as a electrical system design engineer for an over the road transportation refrigeration manufacture. With equipment that is exposed to the weather and vibration, connectors are always a problem.

My goal as a designer was to eliminate as many connectors as possible. However, for serviceability and assembly, some connectors are necessary.

I hate to say this, but those connectors that JD used on that tractor are about the cheapest and poorest connectors that they could use. Sealed connectors are the best.

Richard