TC35D run problem

[Steve in ATL]

Hi all,

I'm troubleshooting my Operator Safety System. The tractor will not stay running if I leave the seat (in neutral, parking brake on, PTO off, etc).

I've checked the following:
both diodes
seat switch
PTO switch
neutral gear switch
parking brake switch
fuel control relay
PTO control relay
Safety system module

All seem to function just fine. I knew the neutral switch was working properly as the tractor will not start in hi/lo range (as it should). I'm getting all the indication from my PTO switch and pparking brake switch.

Any ideas? The only thing that I can figure is the wiring from the PTO switch to the fuel control relay, or possibly the same on the parking brake.

Help!

 

[jinman]

Steve, I'm guessing by your post that you have had the cowlings off so you can check the diodes. Did you swap relays? It could be a relay problem if you have checked everything else. I haven't looked at the circuit in response to your post, but I'm guessing you can see that the PTO light is not on and the Parking Brake light is ON. That's what I get from your saying the indications are that they are working.

I'll try to look at the circuit and get back to you. Right now I'm at my job and don't have the manual.

Frankly, I've had my seat switch bypassed from the first week I owned my tractor, but I understand everyone does not want to do that. I'll see if I can help with some ideas.

 

[Steve in ATL]

Jim,

All indications (PTO on/off, parking brake, etc) are normal, all the way down the the tractor will not start if not in neutral. I pulled every relay and diode in the safety system, including the fuel shutoff relay, and all of them checked OK.

I may try to order a couple just to play "find the broken component through swapping."

Thanks,

Steve

 

[BarnStangz]

IS this TC new or at least with in its warranty? I'd be calling my dealer... I had a problem like yours, except that it was my seat switch cutting out. I jumped it and have not had any problems. You might want to try that just in case... Gotta love all this electronic crap...

Max

 

[jinman]

Jim,

All indications (PTO on/off, parking brake, etc) are normal, all the way down the the tractor will not start if not in neutral. I pulled every relay and diode in the safety system, including the fuel shutoff relay, and all of them checked OK.

I may try to order a couple just to play "find the broken component through swapping."

Thanks,

Steve

Steve, after looking at the circuit, I would suspect either the parking brake switch or the operator safety module...most likely the switch. The parking brake switch has two sets of contacts 1-2 and 3-4. The 3-4 set runs the Parking Brake light, and the 1-2 set operates the "brake set" logic in conjunction with the seat switch. If that set is not working, your tractor should work exactly as you stated, the light would work, but the tractor would die. Most all switches in this circuit only have one set of contacts, but the parking brake switch has two.

Do you also have a mid-PTO? I didn't see where you mentioned that and it also has contacts to consider. They are in series with the parking brake 1-2 contacts.

After looking at the circuit, I think all relays are working properly.

 

[Steve in ATL]

Steve, after looking at the circuit, I would suspect either the parking brake switch or the operator safety module...most likely the switch. The parking brake switch has two sets of contacts 1-2 and 3-4. The 3-4 set runs the Parking Brake light, and the 1-2 set operates the "brake set" logic in conjunction with the seat switch. If that set is not working, your tractor should work exactly as you stated, the light would work, but the tractor would die. Most all switches in this circuit only have one set of contacts, but the parking brake switch has two.

Do you also have a mid-PTO? I didn't see where you mentioned that and it also has contacts to consider. They are in series with the parking brake 1-2 contacts.

After looking at the circuit, I think all relays are working properly.

Jim,

I pulled the parking brake switch and it checks OK.Same with the safety module - checks fine per the shop manual. This is a real head-scratcher. No mid-PTO.

It's gotta be a bad wire somewhere.

Max,

Nope, not under warranty any longer, unfortunately. I'd jumper the wire, except I'm considering selling the tractor (for one wiht more HP), and I don't want the liability of the safety system being non-operational.

 

[BarnStangz]

Jim,

I pulled the parking brake switch and it checks OK.Same with the safety module - checks fine per the shop manual. This is a real head-scratcher. No mid-PTO.

It's gotta be a bad wire somewhere.

Max,

Nope, not under warranty any longer, unfortunately. I'd jumper the wire, except I'm considering selling the tractor (for one wiht more HP), and I don't want the liability of the safety system being non-operational.

I hear you on the safety... Don't want that monster running over someone! Any luck with your issue yet? Or still working on it! I hate things like this, they can drive you crazy!

M.

 

[DieselMonk]

Did you check for broken wires yet?

 

[Steve in ATL]

Just to follow up -

This morning (the first time I've had a chance to use the tractor since I last posted) the tractor would not start. Starter motor would not turn over. I also found the 10A safety system fuse was blown open. I replaced it, tried to start the tractor, and it was blown open again. It was at this point that I noticed that when I turned the tractor on, the PTO light, and both PTO speed (RPMS) warning lights were illuminated, with the PTO lever in the off position. The PTO safety switch still checks OK, but I unplugged it. The PTO light still remained illuminated. I pulled / exchenged several relay with the PTO safety relay and noted that when the relay was removed the PTO light went out. Also, the tratoctor would still not turn over, even after several swaps of the relay. To experiment, I removed the PTO relay and jumpered (on the tractor) pins 1&2, and 3 & 4, and the tractor turned over and started. The tractor would continue to run even with the relay and the jumpers removed. Also, when attempting to re-start, I noted that if the PTO Safety switch was plugged in, the 10A system safety fuse would blow.

I've looked for worn / frayed wires and can find none. I pulled the relay panel and it appears that ever wire there is OK. The only thing abnormal (to me) that I could find were two wires up under the fuel tank where the seat safety switch wiring joins the chassis harness looked to be cut. I'll try to post a picture of that shortly. I'm about to call the dealer and see if I can have the tractor picked up and looked at, as I have very little time to "play" some more with this problem.

Thanks for everyone's thoughts. If you have any further suggestions, I'm all ears, but very frustrated right now...

Cheers,

Steve

 

[Hooked_on_HP]

Steve try jumping one switch at a time just to identify which swich is bad then replace it. When you are checking the switches ,try to do it with them in place but unpluged and see if one of them is grounding out.