TN70DA hydraulic switch issues

[Rowski]

Hello all...

Last summer I had the amber hydraulic shuttle light flashing (code flash) and no shuttle shifting unless the clutch was used. The diagnosis, (dealer tech over the phone) was a bad switch, on the left side of the transmission housing, above the fuel tank. I replaced the switch and everything was fine.

This spring I had the shuttle recalibrated due to harsh forward to reverse shuttle under near full load, PTO speed. But it is not consistent, keeping the grade, load and rpm the same sometimes it with shift o.k. The recal seemed to make it better but it still did the odd harsh shift.

So this week i did a good 5 hrs of field mowing. Got back home was getting ready to store tractor for the day when low trans/steering pressure light came on (red in color). Cycled the key a few times and multiple restarts and the light stayed on every restart. Next day tractor started with no light on. Check fluid, full, clean and not burnt. Drove the tractor 15 minutes on the road to cut another field. Light came on again. Kept using the tractor but was careful, shuttling only with clutch, not running full PTO speed, low ground speed. I could not really tell anything was wrong other than the light.

Called the dealer. They mentioned that there is a service bulletin for switch problem. The switch is ordered. Most likely problem will be solved.


My question is are there any other hydraulic shuttle switches or sensors I should replace. If there pattern failures for other switches or sensors I would like to replace them now.

 

[Rowski]

Well not so good news. The replacement switch didn't fix the light.


Anybody have a wire diagram for the transmision/steering low pressure light?

Thank You!

 

[Robert_in_NY]

Derek, I am sorry to hear your problem and I hope you get it figured out but I do not recall hearing about any other people having this type of problem. So hopefully RickB will read this and might be able to add some insight. Otherwise please post what you learn so if someone else has this problem it might help them.

 

[Rowski]

Robert

I am currently using the tractor. I don't think there is actual pressure issue. Most likely a switch or wiring issue. If I had a wiring diagram and switch location I could diagnose it myself. I really need to get a factory repair manual.

The dealer did tell me that there is a service bulliten out for the switch they sent me. I verified this by a parts manager from a Case dealer, they got bought by the New Holland dealer. he said the JX series, I believe, are very simmilar in drivetrain.

The road tech, who is very very good is hard to get a hold of. Right now he is busy with choppers and hay bines.

I was hoping RickB would be around and have sometime. I hate sending him PM. I mean that his job that he gets paid to do. I don't like to take advantage of free advise.

That's why I was trying to get a wiring diagram. I could then diagnose it myself and get proper parts.

I will post once I find the problem.

Thanks Robert.

 

[RickB]

Post the part number for the switch that was replaced, or PM me with it. Can you move the tractor after start up using only the shuttle lever, or do you have to use the clutch?

 

[Rowski]

Hello RickB,

I don't have the part # in front of me its at work. I do know its the same switch (the one they told me to replace) I replaced a about 13 months ago. That switch got replaced because I had a shuttle light flash with code. The code was 81 if I remember. At that point you had to shuttle with clutch.

As it is right now everything seems to work fine. I can shuttle with no clutch. The transmission/steering low pressure light (red) was only coming on in the begining after the tractor has been used 2+ hours. Then it got to the point where a few minutes it would come on. To now where its on all the time, right after start up. The whole time the tractor has been working fine.

Thanks

 

[Robert_in_NY]

Is this one of the dash lights and if so does it look like a little steering wheel?

My friends TN-V that I was using had a little red light come on. It looked like a little steering wheel and was on the upper left of the dash console but that tractor had a manual shuttle. I never did ask him what that light was about but will in a couple days.

 

[Rowski]

Its on the top row, in center of the warnging lights. It is 2 icons for one light. The color is red, the left icon is a gear with an oil drop in it. Right next to it on the right is a steering wheel. The manual says is a transmission and/or steering low pressure warning. The light has always since day one been on for for about 5 seconds after start up. The manual also mentions something to the effect that its possible for it to stay on under low idle conditions.

 

[Robert_in_NY]

I think it is the same light, only in a different location. I will ask him about it and see if he knows what caused it.

 

[Rowski]

Switch part # 87395493.