I have a 2002 tn75s and had a devil of a time with error codes. I broke down and bought the complete set of manuals. The model numbers for tn's stayed the same, but there were changes about 2004. If yours is after that....well I don't know if the codes stayed the same. As Rick says, there are two sections of error codes. In the power shuttle section there is no error code 34.....it goes from 33 to 35. In the "4wd engage" section, there is an error code 34. Here is what it says.....problem with "Tilting Sensor---Low tension". Cause of activation of code......Voltage at connection 14 is low caused by short circuit to ground or a faulty sensor. It took me 2 years to finally fix my error code 33...which is also a tilting sensor code. That's why I finally bought the complete set of repair manuals. The tilting sensor is on the right side of the dash (I think). You don't have to remove the instrument panel, etc., just the right side of the cover on the dash down below this. The reason I say "I think" is because the chap from the dealership came out and replaced the tilting sensor and had it done before I could get back the barn to see what he was doing. Apparently a very simple unplug and replug and replace the cover. My tractor was doing all kinds of crazy stuff off and on for this two year period. The dealer finally called the factory rep who told him what it was. Of course, immediately after the dealers' call, my manuals arrived!! These sensors are notorious for going out. If I had bought the manual earlier, I think I could have figured it out myself. He gave me the old part and it has something that rattles around inside and if it gets moisture in it, it doesn't rattle around like it's supposed to and thus the fault codes. I hope this helps you. I was ready to ditch the whole tractor at one point. Works perfectly now.
