My bobcat 773 was giving me error code 05-15 so i change the hydrostatic charge pressure switch and is doing the same

When your get the error code, are you able to still operate the loader arms and bucket tilt?

Thanks for the reply. Just to make certain I understand, you have the engine running, seat bar down, all the LED lights lit up at the BICS display, but the machine won't drive and won't operate loader functions. Then, after a few moments, you get beeps and the 05-15 error code, then machine shuts down automatically. Is that pretty much it?

Ok, there's something seriously wrong with this machine. The original code we were dealing with was charge pressure low. Now we get this:

04-21: engine oil pressure (high) out of range
05-21: hyd charge pressure out of range (high). HUH???
04-15: engine oil pressure in shutdown (ECM shutting engine down)
05-14: hyd charge pressure extremely low. Again...HUH???

With the problems you're having, it's not likely I'm going to be able to say what the problem is, there's just too much stuff going on there, this is going to require someone at the machine figuring it out, possibly a Bobcat Dealer tech.

About the only thing I could advise would be raise the cab, open the rear door, and check the whole wiring harness very closely looking for a spot that is rubbed into wires from vibration causing electrical short circuits or grounds. It seems you have one of two things going on here, either something (like rubbed wiring harness) is sending ECM faulty inputs, or the ECM is flipped out.

I really wish I could help you solve this problem, but under the circumstances there's little I can do over the internet. I'm going to opt out of the topic. No need to give me a rating as I'm unable to help with this. And with all sincerity I do hope you find what's bugging your machine. If you do find something and would like my input, please do post it, as I'm curious myself what's going on with this machine. Cheers

Code 04-21 is engine oil pressure out of range on the high side, it's sensing high engine oil pressure. Which is curious, just where (all of a sudden) did that come from? But the really weird part is the hyd charge pressure. It started out giving you a code for low charge pressure, 05-15, then it went to high charge pressure, 05-21, then it gives a code for "extremely low" charge pressure 05-14.

There's something really weird going on here. I'm hoping it's just a problem somewhere in the harness. But there's no way I can say where on my end. I do hope you find what's causing this.