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Wiring Diagram

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  • Wiring Diagram

    I have been trying to get a wiring diagram for a Craftsman lawn tractor for about a week now entailing about 10 hours on the phone and many hours online. I don't understand why the manufacturer won't provide this info, it seems like it's some sort of national defense secret or something.

    They keep refering me to a picture of the wiring harness and telling me thats all I should need to diagnose my problem ( I guess they don't know what a schematic is?) I've tried through Sears, AYP, and local authorized repair centers and no luck. Any ideas where I might turn for help?

  • #2
    If you are not just trying to rebuild a lost harness, then drop a description of the problem here and the mass of brains might be able to help out.

    Civil engineers build targets, Mechanical engineers build weapons.


    • #3
      Try this website:

      Its a site that requires you to join but it has many members with a great deal of knowledge.



      • #4
        OK, heres a little more information about my problem. Recently bought this lawn tractor at an auction. It looked real good but everyone said the engine was locked up. I needed a cheap tractor so I figured if I could get it cheap enough I could rebuild the motor and still come out OK. Only one other guy bid on the tractor and I got it for $200.

        When I pulled the motor out for the rebuild I found there was nothing wrong with the motor, only the electric PTO clutch was locked up from a bearing that had seized. Great news! I ordered a new clutch and reinstalled everything.

        The thing fired up and ran great and I drove it around and all the gears etc. seem fine, however when I turned the PTO on the blades do not turn.

        I then disconnected the wire at the PTO clutch and hooked up a voltmeter. Then I drove the thing around and tried different gears, mower deck up, mower deck down, and no matter what I tried there was no voltage to the PTO clutch.

        I checked the only fuse I could find, replaced the relay (not sure what all goes through the relay, that's one reason troubleshooting without a schematic is a pain). I checked the safety switch under the seat and even put a jumper across it and still no voltage.

        The PTO switch has about seven wires going to it and it performs other functions so without the schematic again it is difficult to know what terminal does what. The PTO switch also has a safety function in it which won't allow the starter to work if the PTO is on. These safety features which I realize are necessary but they sure make it hard to troubleshoot.


        • #5
          I'm a real good electrician, I gutted the wiring harness on the Murray here.

          Tired of all the saftey stuff for the lawyers to have to have. Seat switch, bahh humbug, that is just if you turn it over and the blades land on your head and give you a haircut.

          Machinery is dangerous, no amount of switches will make up for common sense. And the more you complicate things the more problems.

          David Cofer, Of:
          Tunnel Hill, North Georgia


          • #6

            [This message has been edited by japcas (edited 04-02-2005).]
            Jonathan P.


            • #7
              You might want to try this site.


              There is a wealth of information on there. Also, unless you are just trying to keep the tractor original, why not just bypass the original switch, and wire up another if you can't figure out the original setup. Sometimes just running new wires is easier than trying to figure out the original stuff.
              Jonathan P.


              • #8
                Sounds like safety interlocks. The safety switches often go bad. The primary culprit is usually the seat switch but this one will usually keep the engine from starting or kill it if the blade is engaged. It's meant to shut the engine down if you step off the tractor.

                I just bought a new Sears GT last year (22hp/54"). The "wiring diagram" looks like it was drawn by a six year old using crayons. There's no wire color or markings on it! What model is it? I can check the wires on mine tomorrow and let you know, if you like.


                • #9
                  My murray does not have a Electric clutch.

                  Seat interlock, handle for Mower interlock with starter, oil switch interlock, Hydrostat pedal interlock plus a couple more going into the motor case I don't have a clue about. Seat interlock went bad first, then the Mower switch, now the Solonoid is bad. Probably the cause of it all. (too much power going through that circuit smoked the contacts) You have to start it by bumping between the battery cables on the solonoid. No pull rope.

                  Things are too complicated. I just want to mow the yard, I hate to feel I am rewiring the control rod positioning robot in a nuclear plant. I got plans for that mower, a small dump truck. I am looking at self propelled walk behinds.

                  What ever happened to the mowers where you pulled a rope, they started, you pushed a metal bar in and shorted out the spark plug to kill it? Simple, no problems. My father gave me a old mower that was about 15 years old, it had a iron flywheel and would cut tall grass without problems. I still see it, rusted out mower deck and all but still cutting grass.


                  • #10
                    Viking: One good way to isolate the defective part : Hook your battery (or other 12 volt source) to the clutch. If it engages, you know the clutch is good. Then just follow the wires (by cable and color) back toward the battery, relays, interlocks etc. Somewhere you will most likely find that your battery "jumper wire" will energize the clutch on one side and not on the other. Most likely this is where you have a defective or mis adjusted part.If the problem appears to be at a relay, put the voltage to relay coil.

                    If the clutch fails to energize at all, be sure you are getting both plus and minus 12 volts to the clutch (poor grounds are just as likely problems as the "high" side circuit.

                    I usually find it easier to trace from the part not getting voltage back toward the voltage source than to try to figure out where the voltage is supposed to go to get to the load.


                    • #11
                      I would try a couple of is the seat. Mine is bad on the bolens, they wanted about 30 bucks for a replacement switch. I am the only person that uses it, so I bypassed it.

                      The other that is sometimes found is for reverse, automatically kills the clutch when you go into reverse. Mine doesn't even have that option.

                      Do like what was suggested, just hook the clutch up to the battery to see if it works. If it does, and you are comfortable with it, bypass all the wiring that exists for the clutch and wire in a switch that just gives it power.



                      • #12
                        I have a Cub Cadet mower. I have opened the wire under the seat to allow me to lean over to pick up a limb and not kill the engine. I removed the spring that shut the blade off when I went into reverse.

                        I still have the interlock that requires holding the brake pedal down when starting. I think after the engine has oil pressure this lets the engine stay running.

                        There is a relay that controls all the interlocks just above the battery on my mower. Under the hood behind the dash board.

                        I think the reason why you can not get a manual is this would let you see how to disable all the interlocks and the manufacture does not want you doing this.

                        My .02


                        • #13
                          Thanks for all the input and suggestions. It's seems were all on the same track, and yes I already have a switch set aside to "hot wire" the clutch if I can't get a diagram. Also If I were to cut off all the cable ties that bundle the harness it will be easier to manually trace the wires. It just would be so much simpler if I had the diagram. I can't wait much longer as the weeds are about to take over if I don't get them mowed soon!