lexus4jon

Hello, I am newbie here... I have 2006 Lexus IS 350. My A/C heater control unit (without display) stopped working then back on working about 3 or 4 times then completely quit working. I checked the fuses and they are ok. It sounds like to me that the unit probably stopped working. I haven't check the relay. I checked around for a used unit and I see a lot of IS 250 units are for sale. IS 250 and IS 350 units look the same to me. Are IS 250 and IS 350 units compatible? Is it ok to get IS 250 unit and put it in IS 350 car?

Thank you in advance for your reply!