New FSU now blows hot air,help!

[petertn]

Weasel, I will have to try that..the harness looks rather short and i feared snapping the wires if i tried to wiggle the FSU out prior to unplugging.

Has anyone else tried Weasel's method?

[petertn]

Got it done!

Weasel, you were right on the money about the clips. When I finally got on my back and was able to view the clips I saw they both had already been released. At that point it was just about wiggling it free. Chalk one up for the good guys!

[mele4nyc]

Originally Posted by m5james

There is a heater diverter valve, you can see pics of them on Auto Parts at AutohausAZ - OEM Auto Parts - Discount Replacement Parts, Resources and Car Care Tips or Google 'BMW heater valve'. Its near/on the drivers side shocktower. These commonly fail due to lack or regular coolant flushes.

I'm having a similar problem with my X5. When I turn on the A/C I only get cool air through the middle vents. If I set it to top or footwell vents, it blows strictly HOT air. Even if I leave the IHKA on Auto, it will blow cool air through the middle vents and hot air from both the top and bottom vents. Could this heater divert valve be the issue? I also replaced the FSR but seeing Weasel's comments that obviously wasn't the problem.

Edit: I think I'm answering my own question here. I found this thread on the issue and I'm almost positive that gunk in the antifreeze messed up the valves and kept them open. Heater control valve ? - bimmerfest - BMW Forums
It all seem plausible now that I found out the coolant hasn't been flushed in 55,000 miles. What do you guys think? Could it be anything else?

[m5james]

It may still be possible to save your diverter valve with a good chemical cooling system flush. As long as the rubber gaskets where the plungers touch and close up flow, you can bench test the diverter by apply power to it and watching the plungers move. I've seen instances where it was either both the plunger or the gasket had failed, so there was no saving the units sometimes.

For the X5 they're quite cheap though, so if you've still got issues after a good flushing, unless you like to tinker like myself, it may be more time efficient to just replace it. New ones for my 7 are still in the $400 range, which is why I learned how to repair them for myself and customers if possible.