One side africa one side Alaska mostly ends with coolant mixing valve. Bmw part from bmw era.I signed up for the forum so that I could express my appreciation for the great advice and knowledge that has been shared on this thread. I have a recently acquired 2007 Range Rover HSE with rear seat blower that was blowing cool air on the driver's side and tepid air on the passenger's side and in the rear. I was going down the route of troubleshooting blend doors. I even ordered a GAP diagnostic IID tool to look for faults. Then I read the advice on this thread and decided to connect my AC gauges and check pressures. I ended up adding 24oz of r134a refrigerant, which seemed like a lot, that gave me low side pressures of between 26-30psi and high side pressures between 250-275psi at 1500rpm with an ambient temperature of about 97F. The label under my hood says that r134a capacity is either 25oz or 32oz, depending apparently on if you have rear air. I am hoping I didn't overfill, I could hardly believe that it required 24oz of r134a to get the pressures into what I understood to be the correct range.
Even though I didn't end up needing to make the specific repair to my Rover, I particularly appreciate the advice given in post #85 on troubleshooting Dual Coolant Valve and the controller. I bookmarked it for future use.
Thanks again to all of you who took the time to share your experience in troubleshooting your Rovers so that people like myself could benefit and skip some of the headaches that you have experienced.