Bypass seat pressure switch on an XR4155HC

GSVette · Oct 23, 2024

I am experiencing an intermittent no crank condition on my XR4155HC. I’m pretty sure the seat pressure switch is the source of the condition and am considering bypassing the pressure switch.

Pulled the seat bottom and see that it is a simple pressure pad with two wires-I suspect I can jumper the two wires and ‘ simulate’ the seat being occupied.

Before I do this, I thought I’d query the group and see if anyone else with an XR series tractor using a seat pressure switch had done this to bypass the pressure switch? Have a small concern since the machine is all computerized that just jumper in the switch might have unintended consequences.

scootr · Oct 23, 2024

I believe you are correct. Simply disconnect the 2 wires, hold them together and see if the tractor starts without a person in the seat.
If the wires are push on spades plug them both into a small push in fuse.

Eagle1 · Oct 23, 2024

Works on the XG, I put a toggle switch to bypass as needed. Helps to move the tractor from the ground to remove/install backhoe or cutter.

GS650GL · Oct 23, 2024

Sorry to break it to you, but the seat switch has nothing to do with starting. But it's still a good idea to bypass it anyway. If all the safety switches are working, you don't have to be in the seat to start it. The safety switches that affect starting are the hydro pedal neutral switch, and in the pto switch. On gear shift models, there is one on the clutch pedal and the F-N-R shuttle lever. Check your hydro pedal switch on the right side of the transmission. Make sure the pedals are returning completely to neutral. If not, the switch won't let it start. The switch should make a clicking noise when pushing the pedals and letting them return to neutral. The switch itself could be bad or just need adjustment. Hold the key in the start position and wiggle the pedals, you might find the sweet spot where it starts. The pto switch can also cause this sometimes even if you haven't used the pto. There has to be a good off signal from the switch when the pto is turned off. Sometimes turning the switch on and off will let it start. Saw that happen at least 4 times on different tractors. The pto switch could also be bad even if the pto works. All the safety switches feed the VCM control module under the dash. The VCM reads the status of all the switches and decides if it will let it start, and will also shut the engine off if you get off the seat while the tractor is moving. Hydro pedals pushed, or F-N-R in gear on gear shift models. That is the purpose of the seat switch, not for starting the engine. Bypassing it will only allow you to move the tractor without sitting in the seat as Eagle1 said. Still a good idea to bypass it because these seat switches fail or become too sensitive so that if you lean to one side or bounce over bumps, the engine cuts out or dies. If it fails, the engine will start but will shut off when you push the pedals and try to move. A stick or other debris can get up under the tractor and affect the operation of the neutral switch or not allow the pedals to return properly. Key switch could be bad also, but not likely. Make sure all battery and starter and ground connections are good too. The only things computerized are the fuel injection and the emissions controlled by the ECU, so you don't need to worry about damaging anything bypassing it.

GSVette · Oct 23, 2024

Appreciate your insights-there we’re a couple of items that I failed to mention- the ‘ no crank’ condition occurs after the tractor has started and run normally and is then shut down. The ‘ no crank’ condition has been preceded by the annoying beeping alert that usually occurs when I get off the seat with the tractor in a gear range and the parking brake is off however I’m sitting on the seat and usually in motion. Stopping and applying the parking brake silenced the alarm in prior occurrences however yesterday I shut down and got the ‘no crank’. I tried many of the items you noted- cycling PTO switch, neutral on range selector and application of parking brake, shuttling the F/R pedals ( however, I did not try the key in the start position as you suggested).

I will take a look underneath at the hydro position switch- that really seems to be a likely culprit even though some of the symptoms I described above don’t necessarily seem to tie together.

Tractor started and ran a number of times since the last ‘ no crank’ but I am concerned that I’ve not gotten to the root cause of the condition.

Thanks for your insights