Error 33 on TN75DA... ??

[rorkin]

Tractor won't move.. Anyone know what this error code is..
Fuses OK and seems to be plenty of fluid.. No forward or reverse on
shuttle..

 

[RickB]

Transmission dump valve solenoid coil short circuit. First thing to do is locate the dump valve solenoid on the transmission control valve and unplug it. If the fault code changes to 36, you probably have a bad solenoid coil. If not, you have a harness or ECM problem. DO NOT swap the wiring between the dump solenoid and the 'A' or 'B' clutch solenoids.

 

[rorkin]

Thanks for the info.. Any chance the solonoid is stuck ?? tractor was sitting for a while.. Would a tap help ?? How do I find the solonoid ??

 

[rorkin]

Same as error 35 ?? see other post below.


RickB
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Joined: 16 Oct 1998
Posts: 2186


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Posted: Sun May 11, 2008 3:39 am Post subject: Re: New Holland TN70

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Open station TN's without SuperSteer have the diagnostic connector just in front of the firewall, I don't remember which side. All cabbed and SuperSteer TN's have the diagnostic connector (black) near the clutch pedal and fuse panel under the lower left cowl panel. Fault 12 is Clutch Pedal Potentiometer signal voltage shorted to 5 or 12 volts and indicates faulty wiring, potentiometer, or ECM. There are tests in H9, H5, and HA to troubleshoot. Code 35 is Dump valve solenoid or ECM short circuit to 12 volts and indicates faulty wiring, dump solenoid coil, or ECM. There are no H menu diagnostics for this code, but disconnecting the dump valve solenoid coil wiring connector should change the fault code to 36 if the coil is shorted (which is unlikely since there is no 12 volt source at the coil). Be sure to check the shuttle handle/switch for looseness and shorted connections to the mounting bracket as well as running the switch test routines on the FNR switch before buying that new ECM.

 

[RickB]

Similar, but not exactly the same. The source of the short circuit, if one actually exists, would differ. As a solenoid coil has no moving parts, hammer therapy won't help. The TCV is inboard of the left rear wheel; the dump valve solenoid is at the bottom of the TCV and the A. B, and dump solenoids are labelled in the valve casting.

 

[rorkin]

Ended up at dealer who said ecm had no memory.. Suggested that battery had run down.. I explained that there was enough battery to start the unit
and that was not the problem.. He said that even though there was an error code it was not in the memory.. I thought that the memory was non volatile
flash.. Is it possible for it to loose memory with dead battery ??
If so how long for memory to die ?? He says they can not re flash and had to put in new module.. $500 +.. Could this be so poorly designed that it can end up costing that amount from a dead battery ??.
Since he can come up with no other answer I guess the module just failed
on its own.. Which is odd since the tractor was parked and when I came back .. Would not move..
Any thoughts ?? I do not have a lot of confidence in this dealer.
Thanks

 

[RickB]

Ended up at dealer who said ecm had no memory. Is it possible for it to loose memory with dead battery ??

It is possible, although not common OR normal. If your battery isn't dead, it's a moot point.

If so how long for memory to die ?? He says they can not re flash and had to put in new module.. $500 +.. Could this be so poorly designed that it can end up costing that amount from a dead battery ??.

If he can't re-flash it, his staff is underqualified and/or his shop is underequipped. Again, a DB should not cause this problem and if that alone was the cause, a reflash would cure it. Based on your description of the symptoms and surrounding events, I pretty much agree with his diagnosis, (assuming the rest of the troubleshooting tree was followed for that fault code) but disagree with the way he reached that conclusion, and his unwillingness/inability to reflash your controller. Reloading the existing or better yet, later level software should be part of the repair process in many cases where a controller failure is indicated.

Since he can come up with no other answer I guess the module just failed
on its own.

Unfortunately, that does happen occaisionally.

 

[rorkin]

Well first he told me there was no such error code. What he did was simply
install a new module, which I would assume would have the latest revision.
He is letting it sit to see if anything else knocks out memory.. Seems like a rather weird approach to me. He offered welding on the machine or lightning as a possible cause.. All of which did not happen. Is there anything else that you know of that could have taken out the memory that he may not have found or looked for ?. I suspect he did not trace out that error code but will check with him.

 

[RickB]

Well first he told me there was no such error code. What he did was simply
install a new module, which I would assume would have the latest revision.
He is letting it sit to see if anything else knocks out memory.. Seems like a rather weird approach to me. He offered welding on the machine or lightning as a possible cause.. All of which did not happen. Is there anything else that you know of that could have taken out the memory that he may not have found or looked for ?. I suspect he did not trace out that error code but will check with him.

I'm not going to throw the guy any further under the bus than I already have..... Suffice it to say I would have approached this problem differently than you are telling us he did. I can't say the end result was wrong, but I don't understand how the determination was made that the non-volatile memory was gone, or in fact, why it was gone, or why no attempt was made to restore it if it was gone.

 

[rorkin]

I'm not going to throw the guy any further under the bus than I already have..... Suffice it to say I would have approached this problem differently than you are telling us he did. I can't say the end result was wrong, but I don't understand how the determination was made that the non-volatile memory was gone, or in fact, why it was gone, or why no attempt was made to restore it if it was gone.

He told me that New Holland refuses to let the dealers re-flash the memory.
Guess that is not true. I will check with another dealer unless you work for one.