Traction Problem with load mode 4120

[tschwerm]

Have a 4120 and when i switch the load switch to the on mode the drive doesn't move the tractor unless you run the tractor at above 1500 rpm is that normal?

 

[fuseboxer]

Load match is a mystery to me I will be looking fwd to expert knowledge imparted in your thread. I think of it as an improved CPU controlled governor. The old style mechanical governor is not on our units. If you push load match on with the RPM at low idle and the engine not running when you start your tractor do you find it a nice anti-theft feature? Will not move? I think I have experience this but not totally sure. Using the search engine of the old threads on load match is interesting.
Scooping dirt with my 300CX with load match in the off position and the trans in the "A" position my RPM's can drop some. With the load match switch turned on the RPM's and probably the torque stay constant sounding.

 

[fuseboxer]

Just got back in from out side playing with the tractor in the different gears and with and without Load match on. It likes the lower gears and higher RPM but will move at idle in all three gears with load match on. What I believed that it would not move I could not replay. Must have been in netural.

 

[tschwerm]

Thanks for the input fuseboxer I remember when I got the tractor about a year and a half ago that it did run even at idle. I was working on my sisters horse ranch where she had about 100 trees to clear and put it in the load on position and it would not move.

 

[tschwerm]

UPdate I had the JD dealer out today to check out the load match mode.

Worked on it most of the day could not figure out the problem. he decided to recalibrate the sensors . tried many times but the tractor would not calibrate.

now it doesn't move at all.... this is horrible I am not happy. now he is thinking it might need a new control module... 580 bucks..

Any one have any ideas???

 

[fuseboxer]

You wrote: now it doesn't move at all.... this is horrible I am not happy. now he is thinking it might need a new control module... 580 bucks.

Having a JD tech on a house call is like having a medical doctor making a house call with advice. Very few people are going to offer advice, many that post on tractorbynetare are JD tech's or connected.
I assume he is comming back with a CPU in the near future. I am supprised the tractor was not taken to the shop.

Be sneeky and reset your CPU and when he comes back before he swaps out your CPU for the big charge have him try to calibrate once more.
I believe if you disconnect the battery Positive for a Minute then reconnect the memory error of the cpu may clear. Let me know if you tractor at least moves after you disconnect the battery. Leave to Load match on off.

 

[tschwerm]

We did disconnect the battery but not for 1 minute. I then turned on the ignition while the battery was disconnected thinking if there was any charge left in the module turning on the ignition would discharge the module capacitors
I think it did because the start up sequence seems quicker.

 

[fuseboxer]

Too bad they do not give a credit for your old CPU. Your JD tech is the way to go you tried the best you can. Was you tractor left on top of a hill in a lightening storm? When you use search on tractorbynet ,CPU, many threads but did not see confirmation of replacement. JD mfg does a good job sealing up the CPU and having a triple seal on the grounded massive plug. The whole unit is sealed in a can. When I took mine out to examine I question if it has the ability to withstand an "electro magnetic pulse ".

 

[tschwerm]

Tomorrow the replacement module should arrive at the dealer. They winched my tractor on a truck and hauled it back to the dealer yesterday. they claim they may have it back to me before the day is done....we will see. They are trying.

 

[tschwerm]

Problem is not going away JD dealer does not have an answer... Now they are consulting with tech support module is not talking to sensors

 

[Kyle_in_Tex]

Yes it is normal. I really hate to tell you this, but load match doesn't work or should I say it works too much at low rpm. It is designed to keep rpm from stalling, so how can it possibly work if the rpm is already at a low setting? Don't use it except for A or B gear and at higher rpms only. Like 2000 on up.

Hope your dealer doesn't charge you for nothing. Wish you would have waited a bit more.

 

[chevyman29]

well after two trips to the dealer i'll tell you how I fixed my load match problems on my 4520 . I traded that sucker back in on a 5095m with power rev plus . cause im telling you right now the people at my dealer DONT have a clue as to how to fix loadmatch problems or even really understand how it should work . i wish you the best of luck and will stay tuned ......

 

[PioneerMan]

I have a friend with a car that has a 'sport' mode, which basically adds more fuel. I think it is the same thing, just when the engine struggles. If it is at idle, or low rpms, it cant really recover no matter how much fuel is added. If it is what I am thinking, it will not help at full throttle either, because it is at max fuel burn. My .02.

 

[Kyle_in_Tex]

Re thinking a bit more how to explain it. Load match is designed to get the maximum HP out of a tractor. So it works when the engine is at full RPM. In motorcycling terms we say WFO. It is designed for getting a full load of dirt in the bucket, or for mowing thru various thickness of grass. It will automatically slow the speed down to keep the RPM up when you hit really thick grass. All too often, owners think they are taking better care of a machine if they don't "rev it up full". Nonsense, these engines are designed to run for thousands of hours at full power. Don't baby them. It is far worse to have an engine working hard and then stall it so much it dies. If this happens, start it immediately to get the coolant circulating to the hot spots in the engine per JD's recommendation.

 

[tschwerm]

Why wouldn't the dealer know? When it is working right.

This is very frustrating

 

[tschwerm]

Kyle does your tractor move at all at idle in power match mode? Mine did not until you hit about 1500-1800 rpm

 

[fuseboxer]

Without load match my rpm's and power drop under load. When I put a 5 foot garden box with 5-chisel plow tines down I have to have load match on or the unit will die. I need to have the rpm's up near the 540pto mark and then push the load match on. The clay soil/grass untilled soil will rip or tires spin some and rip. Without the loadmatch the engine rpm's drop and the engine dies. I do not hear any rpm drop with load match. Old mechanical governor tractors you could tell the fuel was increased/throttle. Load match is different its engine is computor controlled sequential fuel injection with high tech sensors. I am sure it is high tech.

Compare the old gas auto's that lost power climbing the mountains now they do not miss a beat. High tech, Mass air flow, cpu control and fuel injection with lots of sensors. Europe had the technology applied to car diesel engines and the USA only had it on gas engines. USA diesel engine high tech I am sure has improved in the last 5yrs but I do not know if it matches the EU. The old Cummings and other diesel trucks would continue to down shift uphill and the low flow turbo helped. High psi turbo can peak hp but cut engine life. My son had a full race cam gas v8 the life was about 500 miles and dead eng.

 

[Kyle_in_Tex]

Kyle does your tractor move at all at idle in power match mode? Mine did not until you hit about 1500-1800 rpm

No, it won't work until you get up to full power rpms.

 

[tschwerm]

Great news tractor is back, they found the throttle speed sensor loose and it had rotated 180 out of position.

They upgrade all the current codes in my module and did not charge me.
They felt the sensor was loose from the last time they serviced the tractor.

 

[chevyman29]

glad to hear that lets hope it stays working right for you !!!