XR4040H Won't Start

Endless47 · Thursday at 1:14 PM

I used the tractor a few weeks ago, no issues. Went out and it won't start now.

Key on - everything is acting normal; glow runs for a few seconds, fuel pump ticks like normal, the battery, oil and park brake lights are on. Nothing happens when I turn the key to start position. No voltage to the starter solenoid.

All lights function.
Fuses are all good.
Hooked battery charger up and it said 80%. I let it charge to 100%. I checked voltage from + post, alternator and main starter wire to the neg post and various other ground points on the tractor and all read exactly the same voltage so I don't think I have any ground problems. I also hooked up another car battery just to be sure the tractor battery isn't shot but no change.
HST Neutral switch seems good. Reads 1.5ohms when the pedals are neutral and goes open when either pedal is pushed. I put a jumper across in the harness plug anyway and still no start.
PTO light on the dash turns on/off as I turn the PTO switch on/off. Tried it several times. I don't know if there is anything else to check here?
Ignition switch seems fine. I get continuity from the BW wire to WR wire when "on" and continuity also to RY when in "start" position.
Starter relay reads 85ohms across the normally closed terminals. I guess that's ok? I don't hear it click but don't know if I would or it may not even be getting signal to close. I'm not sure which pin to check for voltage when the key is turned to start. I swapped in a relay that had the same pin diagram and still nothing.
I disconnected the battery for a while, hoping the ECU might reset, but no help.

I jumped the starter solenoid and it started up like normal. I let it warm up for a min and ran it around for a bit. No lights or codes on the dash. It ran like it should. Still won't start from the key though.

Anything else to check?

Would the cruise control button have any effect?
Is there a switch for HST 1-2-3 range lever neutral?

Avenger · Thursday at 2:21 PM

The cruise control shouldn't have any effect on starting operations, but turn it off anyway.
Did you try to jump the key switch? Can you turn the tractor off from the the key?

Typically, when a vehicle wont start by the key switch, but will by jumping the starting solenoid, the problem is with the switch... Typically.

GS650GL · Thursday at 3:16 PM

It sounds like you have done a thorough job trying the obvious things like key switch, pto switch, relay, and HST neutral switch. On an MT3, the range lever has to be in neutral but on an XR4040 I don't think so. The pto switch and HST neutral switch should be the only safety switches that affect starting. The seat switch doesn't prevent starting, it only shuts the engine off if you get out of the seat while the forward/reverse pedals are pushed. If you have an optional mid pto, the lever has to be in the off position. Is there more than one fuse box on this model? Sometimes there are more fuses somewhere else that need to be checked. Also, there is a control module under the dash (sometimes called HST relay or module, even if it doesn't have HST transmission) that reads all the inputs from the safety switches and decides if it will let the engine start. The small wire on the starter solenoid that energizes the solenoid and starter sometimes doesn't make a good connection. It is a flat spade push-on connector and I have had to squeeze the plug with pliers to make it fit tighter on the flat spade to fix an intermittent no start. Even if your safety switches are good, there could still be a problem with the wiring. The start relay definitely should click when trying to start it. If not, it's not getting power from the key switch which goes through the safety switches and HST relay. Could also be a bad ground, but that usually causes other weird symptoms. Also, the pto switch can seem OK and the pto might even work, but it can still fail to send a pto off signal to the HST relay when the switch is off. Good luck, let us know what you find wrong.