99 GC heater error codes.. Need Help

I have a 1999 grand cherokee limited that the heat and ac just started acting up on me. I checked the codes and this is what I got.
20=Mode door travel too large
56=right temperature door travel too large
54=left temperature door travel too large.
When I was checking the codes the drivers side temp knob was touched and displayed 1. I noticed that you can adjust both of them from 1 to 89. Does anyone know how to fix this or the correct adjustments inorder to get the heat and ac working again. I tried asking the dealer but of course they say ill have to bring it in for that.

Any help will be greatly appreciated.


Thanks

sorry to be the bearer of bad news but it sounds like your blend door is broken. I have the same problem on mine and I don't get any heat on the passenger side. The whole dash has to come out and the blend door has to be replaced. It is a pretty expensive job.