2555 HST Cab Electrical problem- Need to jump starter posts to start

[sdoubledub]

Having an electrical issue. Have full charge on battery, and connection to battery is solid. Have full lights on dash when key is on. Will not start without jumping starter posts. When it runs throttle will only idle- I have no throttle control, regardless of position. Oddly, it will engage in fwd and reverse, but only limping at idle. When trying to start brakes are engaged, pto disengaged, hydraulic controls all in center. Mid pto is disengaged as well. Does anyone know where all of the different safety switches are located? I checked the seat and the ones under the hst pedals under the cab. Hopefully someone can give me a little guidance as to how many there are, and where they are located.
Thanks in advance

 

[Jabonee]

Safety switch would not effect throttle.

 

[sdoubledub]

Safety switch would not effect throttle.

I was told by dealer to check the 10 amp "engine stop" fuse. I checked the "controller" and that was fine too. (I have NO clue what controller is for).
Unfortunately now I dont have glow plugs, which I had yesterday. This is fresh off of the tractor coming back from the dealer to chase down a short in the radio wiring that was draining my battery. Do you know what might be keeping the throttle disabled?
Thank you.

 

[L120]

In the olden days, I could confidentially tell you it is the starter solenoid has gone bad. With today's outterspace alien tech just to make a simple diesel engine run, it gets complicated real fast. They're designed that way.

 

[Jabonee]

What you are describing is a power issue. Mahindra tractors are notorious for faulty connections do to corrosion. Your unit has a power connection just below and behind the battery. I've seen that plug fail on several tractors. Locate the Mega fuses on the left side of the battery and follow the wires. Note one is for cab power the other is for the tractor. I suspect the circuit is opening when a load is applied.

 

[sdoubledub]

In the olden days, I could confidentially tell you it is the starter solenoid has gone bad. With today's outterspace alien tech just to make a simple diesel engine run, it gets complicated real fast. They're designed that way.

Interesting you mentioned that. It failed while it was at the dealer (new development) and they replaced it. Even when I had to jump the starter yesterday, we are at a loss for why I have no throttle control. When they previously jumped it, they had full power to bring it in, move around the yard, etc. I guess we'll have to verify the starter solenoid again. Is there a condition that could make a new solenoid go bad in a couple of days, or just lousy luck with a bad part?
Thank you.

 

[sdoubledub]

Safety switch would not effect throttle.

Update for others. According to Mahindra service tech, they advised checking for loose wire/ pushed in pin at the connectors coming into cab. All pins and wires appear connected properly. They now think it may be transmission controller, as voltage checks out, starter switch engages, but no start (new solenoid). Glow plugs operate only in the on position - turn key to glow position and still nothing. Service rep driving up to dealer today. Will update.
Thank you to all.

 

[sdoubledub]

Final (hopefully) update. There were 2 issues that apparently happened simultaneously. I find that a little hard that there appears to be no direct cause and effect.

The no starting and having to jump the starter solenoid was after all the messing around the white harness clips from the firewall to behind the dash. We must've tried that no less than 8 times, so be patient and aware. They are greasing the connectors, zip tying them, packing the engine side back of the clip and siliconing around the clip to seal the access to the cab better. The clip also was responsible for the no glow plug side of the ignition.

Jabonee was correct. The throttle issue was not from a safety switch, it was from a bad transmission controller.
So even though the engine ran (after starter jump) AND moved fwd and rev, the controller over ride the throttle. As a short term solution, I wrapped a bungee around the loader frame and manually attached it to the throttle mechanism and was able to get ample rpms in a pinch.
Still at a loss as to how chasing down a battery drain and installing some goodies turned into a new starter, harness problems and a bad controller, but it should be fixed nonetheless.

Thanks for all of your responses

The loss of throttle

 

[Jabonee]

It sounds to me like your dealer is NOT up to speed. There is a " Field Mod" for those bulkhead connectors you are referring to. They should have checked that by sn#. You run the risk of uncomanded movement as well as the electrical issues you have described. Shorting can occur causing the controllers to fail. Did you by this unit new ?