Auto transmision not selecting any gear.
 

Auto 850 built June '94. It is not selecting any gears at all. No flashing lights, but I have not checked the codes yet, as I will be learning something new when I do. The engine changes note when selecting a gear, but definitely no gear engaging at all. Fluid is reasonably clean and not burnt at all. I assume torque converter problems would result in burnt fluid? So I am assuming pressure problem. Any other ideas? I have dealt with PnP switch issues before, this appears very different. When it stopped working there was no warning at all, just stopped and was working perfectly before. Thanks.

With someones help I'd watch the arm on the transmission while someone shifts it through it's gears and see if the arm is moving. If the arm is moving you know it's in the transmission and not the linkage, cable or shifter itself.

Yep, those parts are all working okay. I know it is trying as the engine note changes when you select a gear. So there is some sort of load, but it can't be felt, no vibration at all.

Either the pump has gone out or the torque converter has failed.

Yep, that's my thinking. I am going to attempt to give the on board diagnostics a go and also a pressure test. If anyone else comes up with any ideas let me know... Looks like I have a fun job ahead of me replacing it otherwise!