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2012 Classic T Electrical Issues

#1

Grhopper

Grhopper

Last year I bought a 2750T from a guy that used it at his house. Not sure if he's the original owner or not, but it has less than 500 hours, so I don't think it was used in a commercial business. When I bought it, the guy said that it wouldn't start by the switch, he had to use a wire to jump from the battery to the starter. In order to do that, he did something to bypass the seat safety switch. I'm not sure what other safety switches are bypassed.

I didn't have any issues with it last year. It started fine the first time I went to use it this year. The next week I couldn't get it to start. As someone that doesn't know much about engines, I figured I'd start cheap and move up. Changed the spark plugs, air filter, and replaced the carburetor. I planned to change the oil as soon as I could move it to another location. I checked the oil level and it is good. Then I got some help from a neighbor, and we figured out that the plugs weren't getting any electricity. He tested the key switch and everything seemed fine.

One day I got it to start, but when I turned the PTO switch on, the engine cut off. I ordered a new key switch and PTO switch and replaced those today. Still nothing. I've charged the battery multiple times during all of this. I'm not sure what to check next.

Usually, when I turn the key to the on position I can hear a faint solid beep sound (best way to describe it). Currently I do not hear that sound. When I got it to start the other day I could hear the sound.


#2

B

Born2Mow

Sounds like your issue is in the starter safety interlock system, and not the starter or engine. The seller definitely had to do some work to bypass the seat safety switch in order to get off and jump the starter. Now, you may have an additional switch failing. Start by testing all the switches and then trace out all the safety interlock wiring to make sure it's in good order.

Bypassing ANY of the safety interlock is a very BAD idea.


#3

Grhopper

Grhopper

I found the wiring diagram in the 2012-classic-t-parts-manual. Is there anywhere that has pictures of the location of the switches?


#4

B

bertsmobile1

No .
Only Deere shows where switches & plugs are located in the technical manual.

You have a problem with the seat switch .
The switch has an anti tamper plug on it o stop people doing what the original owner has done
Reconnect it and your problem will go away.
Usually people bypass the seat switch to prevent the engine cutting out when driving too fast over bumpy ground .
If that is a problem for you then pull the switch apart and put a screw into the end of the plunger to desensatize it


#5

B

Born2Mow

The "seat switch" is usually under.... wait for it.... the Seat !! :ROFLMAO:

What I suspect is that the switches are OK, but that the PO butchered the harness trying to by-pass the safeties. Probably not real pretty.

Good luck.


#6

Grhopper

Grhopper

I've used it both with the seat switch connected and disconnected over the past year.

eSihjsg.jpg


Is this black box a normal connection, or should the grey plug be plugged into something? There are 5 wires that go into the plug. When I disconnect the 2, there are 4 pins coming from the black box to the grey plug.


#7

B

bertsmobile1

As Born2mow mentioned, the DPO butchers the wiring to bypass the seat switch
The grey plug has a bridging terminal in it that shorts the wiring if the other side of the plug is removed ( usual method of bypassing an N/O type switch )
So the black half is part of the original seat switch .
I have one have I use when working on these engines because it is quick & convienant to be able to start & run the mower without any one in the seat for the purpose of diagnosis & adjustment.


#8

Grhopper

Grhopper

With the way things are pictured, does that rule out the seat safety switch? What should my next step be?


#9

Hammermechanicman

Hammermechanicman

I've used it both with the seat switch connected and disconnected over the past year.

eSihjsg.jpg


Is this black box a normal connection, or should the grey plug be plugged into something? There are 5 wires that go into the plug. When I disconnect the 2, there are 4 pins coming from the black box to the grey plug.
Might be a 925 1648 relay


#10

Grhopper

Grhopper

Based on the picture of a 925-1648 relay on Amazon, that is not the same relay. The one on my mower has 4 blades in a row.


#11

Grhopper

Grhopper

While moving the wire harness around I started to hear the low oil pressure tone. It only sounded when I had the harness in a certain position. I began testing the fuses for continuity. They all looked fine visually, but the top one didn't have continuity. I replaced all 3 fuses and the mower is running again.

I still have the issue that I can't start the mower with the switch. I replaced the key switch and the PTO switch. I also tested the seat switch, 2 arm switched and the break switch for continuity. They seem to be working fine. Someone I spoke with said that I probably have a short on a ground wire somewhere. The only wiring that I see that has an issue is the 12v accessory port. It looks like it was cut off. Would that cause issues?

Reminder, to start the mower I turn the switch to on and jump from the positive terminal on the battery to where the blue wire connects to the starter. After the engine starts I disconnect that jump wire and cut the grass. Turn the switch to off when done.


#12

B

bertsmobile1

You have a wiring / switch problem
To help you further we need the full model & serial so we can check the wiring diagrams
Dixie usually use some relays in the starting circuit
If the lap bar & parking brake switches have only 2 pins then a relay or control module is used.
If they have 4 pins then it will be a simple daisy chain


#13

Grhopper

Grhopper

2012 Classic T 2750 serial # 12CT2750KWGTPXXXX

The lap bar switches have 4 pins and the brake switch has 6. All 3 of those switches tested correctly.


#14

B

bertsmobile1

2012 Classic T 2750 serial # 12CT2750KWGTPXXXX

The lap bar switches have 4 pins and the brake switch has 6. All 3 of those switches tested correctly.
My normal method of diagnosing these problems is to bypass the switches one at a time by jumping the plugs
If that does not work I bypass the wiring by jumping from one plug to the next one
If it starts to look a bit overly complicated then I pull the kill wires off the coils just so I don't accidently send voltage down a kill wire

I will see if I can't dig up a schmetic from some where .


#15

B

bertsmobile1

Remember the kid in drawing class who grabbed every colour pencil and used every one in every drawing ?
Well looks like he has done growed up and now works for Dixie Chopper and uses the same pencils to draw their wiring diagrams.
And they are about as useful as his drawings of "my doggy"
   2012-classic-twirel.jpg
   2012-classic-twire2.jpg

Now if you can follow the colours without spinning out.
The starting solenoid power comes from D terminal on the key switch ( again connection from B to D not shown ) via the dark blue wire to the PTO switch where it changes colour to light blue
Then it goes to the right lap bar switch where it changes colour again to dark blue or perhaps purple
This goes to the brake switch when it turns light blue again
Next is the Left lap bar switch when it turns dark blue and from there to the engine plug and the starter solenoid, ( not shown but a good guess )
More of a pansy chain than a daisy chain but there you have it ,
Just be thankful they did not toss some relays in there for the fun of it


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