Hello Smart friends, I’ve been having a problem with my Smart fortwo for 2 days now. the following to the vehicle: Smart Fortwo MHD 61PS (Benzin) Bj 4/2011 without climate and 52000km. I did the following action 2 days ago: Changing the rib belt without opening any cooling circuit and without having removed any plugs. Alternator tightened back, strap old down and strap new on it. Running direction etc. everything noticed and also voltage checked. Engine runs 1a and also MHD works great. I don’t know if it can be related to it, but the following problem: My heater only blows cold air out of the ventilation. There’s no difference between warm or cold. Engine runs 1A and does not overheat either. Cooling water in the tank is also hot and without excessive overpressure. Heating blower works perfectly in all stages, but only cold air comes up. I have read similar problems with air in the heating circuit. I can’t shut out because I’ve changed nothing on this and the compensation tank is both since 20km. Heating blower works perfectly in all stages, but when there’s no hot air is used.