Roomba discovery acting wierd

Robot runs fine with no main brushes, as soon as I put them in it runs fine on hardwood. When it tries to go up on a carpet from hardwood it backs up. If I start it out on carpet with brushes the brush motor stalls. I cleaned both drive wheel encoders, all ir sensors, and cleaned the brush transmission. Any ideas? BIT passes. I was thing drive wheel spring tension?

Thanks in advance for your help,

Jeff

Hi Jeff,

It seems you have contacted our support center for this problem as well.
Please reply to our technician via the ticket for troubleshooting.