Next time you shut the car down, manually turn the CCU off using the blower speed button. When mine is in its intermitent failure mode it works correctly about 50% of the time after restarting. Sometimes the blower comes back on 30 minutes into my commute too. Never fails to come back on, is just a question of when sometimes.

Option #3 to what Marty said would be retrofiting your (E) regulator using one from a W140 that is available separately. I beleive there is a write up in the DIY section concerning that.

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)