4210 ehydo calibration help

[Big Jon]

I had lost my cruise control years ago never thought about it much as not really used. A few years ago started loosing power to the load match, drain and changed fluids and cleaned suck screen, everything seemed back to normal. Then I noticed forward and reversal pedals were getting weak and tractor not moving. When I pushed pedal (either one) they were not coming back up fully and replaced the torsion springs and back to normal again. load match lost power and I did not see any codes. Tractor runs fine in MFWD without load match. I should have left well enough alone but wanted to get by green buddy back on its feet. I received a manual from another person on this forum ( a shout out to and big thanks to another 4210 owner in Georgia), and started tinkering.

Well I am not a mechanic buy no means but can worm my through many different tasks. I put my tractor in calibration mode (big mistake as once it goes in you must clear all codes). Well I am stuck with my tractor on stands and cannot get it out.

Started going through this forward pedal pot, reverse pot, then throttle pot kept coming back to forward pot, adjusted forward pot and finally got it to pass from many minor tweaks. Then start over, forward pot passed the rear pot passed and to throttle would not pass, RPM set to low, adjusted, forward pot passed, reversed pot passed, then throttle pot passed, now on to forward valve, did not pass, spit code of mfwd sensor and flywheel sensor. Replaced both back through it again. Forward pot passed, rear pot passed, throttle passed, went to forward valve then rear wheel moved went to reverse valve and nothing and spit code of flywheel sensor. Tested again forward pot passed, rear pot passed throttle will Not pass and spits flywheel sensor. Voltage at all pots 5 and continuity at ground, sinal wire if reading this correctly has 2 volts at throttle pot and I think should be reading .04v at low idle, I think.

I noticed when I adjusted the rpm as it was to low for calibration the linkage arm has been adjusted (I adjusted the stop per manual) that it was set previous at factory about 2 inches away from it is now farther down the rod. Tractor went in for a few warranty issues not related to any of this.

I am looking for some serious help here as I know that in this forum there many more intelligent mechanics than I.

Sorry for such a long post but really wanted to give a history before questions come in.

 

[mfreund]

I was going to say flywheel sensor, but you changed it. I would adjust the arm to make the v at the potentiometer be .4v and try to calibrate.


I would caution anyone who thinks Calibration mode is going to fix any problems. Most of the time it is a pain in the rear and causes more problems. There are a list of repairs that require you to recalibrate. If you did not do any of the do not move the fuse!!!!

 

[Big Jon]

I was going to say flywheel sensor, but you changed it. I would adjust the arm to make the v at the potentiometer be .4v and try to calibrate.


I would caution anyone who thinks Calibration mode is going to fix any problems. Most of the time it is a pain in the rear and causes more problems. There are a list of repairs that require you to recalibrate. If you did not do any of the do not move the fuse!!!!

Agreed and lessoned learned

 

[Big Jon]

I really hope I get some serious inputs from all you master mechanics. :anyone:

 

[Big Jon]

I was going to say flywheel sensor, but you changed it. I would adjust the arm to make the v at the potentiometer be .4v and try to calibrate.


I would caution anyone who thinks Calibration mode is going to fix any problems. Most of the time it is a pain in the rear and causes more problems. There are a list of repairs that require you to recalibrate. If you did not do any of the do not move the fuse!!!!

Mfreund
Question- I am definitely trying to adjust as know this makes the only logical step for the throttle pot but my mind just doesn't get how a mechanical linkage can change the voltage. As I said not a mechanic.... Definitely thanks for input.

The set screw is seized and tried lubricants etc. What would you think of some precession heat?

 

[mfreund]

Is the rpm right at idle? Can you adjust the potentiometer at the throttle linkage instead of actually changing the rpm speed? That is what I would try first. It is under the plastic rt side of throttle.

 

[mfreund]

I really hope I get some serious inputs from all you master mechanics. :anyone:[/QUOTE

Unless you have one there would be no way to learn. My local dealership kept putting me off until I got mad and bought a tech manual and fixed it myself. Not a huge base of knowledge. There is a couple more than me. Proably better too! Lol

 

[Big Jon]

I have the throttle pot exposed. I adjusted the RPM from the stop before I exposed the throttle pot. That's were I noticed the set screw marks on the linkage rod has changed once before. Book calls for 1000 rpm low idle plus or minus 50, it is running after adjustment at 975 rpm.

 

[mfreund]

Now can you adjust the POT to spec? It is at the right speed now need the POT to read correctly.

 

[Big Jon]

Mfreund,
Its been hectic at work and have not had time to get back to it will try it tonight.

 

[Big Jon]

Now can you adjust the POT to spec? It is at the right speed now need the POT to read correctly.

Mfreund
Let me rephrase previous post.
I have tried adjusting the throttle pot after I got the rpm to spec 1000rpm + - 50. On a cold start it is near 975 as she warms up around 1000 rpm. After rpm set played with pot from one one adjustment far left to another far right and it would not pass.

 

[Big Jon]

Mfreund
Let me rephrase previous post.
I have tried adjusting the throttle pot after I got the rpm to spec 1000rpm + - 50. On a cold start it is near 975 as she warms up around 1000 rpm. After rpm set played with pot from one one adjustment far left to another far right and it would not pass.

Set screw is seized sprayed down with lubes waiting to break free to reset linkage arm to original spec then I will adjust pot again to see if I can get it to pass...

 

[mfreund]

If you use a digital volt meter, check the V between the middle wire and ground. You should be able to set it at Bottom Of Travel (BOT) and Top O Travel(TOT). Then try the calibration.

 

[Big Jon]

Well finally got it. Replaced the throttle pot and adjusted, and adjusted and adjusted. Had nothing to do with the lower linkage. You can actually complete this without JD part to calibrate and just complete with a descent digital meter. It is spitting another code of the cruise which I believe was causing me problems. The low idle voltage was just barely within spec the fast idle was dead on. Just cleared the low idle voltage by 0.1v.

I trace the code of the cruise down to a bad switch.

Thanks mfreund for the help.

 

[mfreund]

I have been off for a while, I am glad you are back running. As I said before the calibration will not fix any problems and will likely cause more problems. That is the voice of experience.

 

[TheBusGuy]

Good morning everyone. I apologize in advance for this post being long winded.
Jon and I have been working feverishly the past couple days to get to the bottom of this "code 4" flywheel speed sensor issue.

What we have:
1. 5v reference on all potentiometers, throttle, fwd, reverse.
2. Both the mfwd (org/blk) and flywheel speed sensor (red/blk) show 5v reference.
3. Their signal wires brown and green are both showing 2.395/2.4v with the key on.
4. The mfwd reference voltage drops iirc with the tractor in motion and the throttle signal Voltage follows the throttle position so both sensors seem to check out.
5. Battery voltage at the rear pto, load match switch, and brake light switch.
6. 925+/- 25rpm low idle speed and 2810+/- 25rpm high idle speed.

I'm sure I'm leaving a few things out since I don't have the tractor in front of me at this time. Hopefully Jon will be along soon with input on what I may be missing.

 

[beenthere]

Who's "Jon" ??

:welcome: to TBN

 

[TheBusGuy]

The OP. The gentleman who started this thread

 

[beenthere]

OK, got it. Last post 2 and half years ago. Goes by "Big Jon"

 

[TheBusGuy]

Roger that. No sense in starting a new thread for what is somewhat the same issue. Glad we're on the same page here now, BeenThere.