E320 constant heat problem? (not the duo valve)
 

After research I thought this was due to the duo valve so I replaced it and the symptoms did not change: constant heat unless AC is set to MAX.

I tested the valve I removed and found:
1) Taller cylinder seems to be a pump and it buzzes (turns?) with 12V
2) Smaller cylinder is the magnetic valve and it seems to close properly. I blew air into it with my hand on the other three ports and it stopped with 12V applied so I likely replaced a good valve!

The climate controller (cc) seems to operate for each button.

I rechecked the connector(s) voltages with engine on:
1) cc off: valve 11.90 (closed), pump 0.60 OK ;)
2) cc & blower on, knob to cold: valve 0.56 (open), pump 11.43 (on) CONSTANT HEAT :confused:
3) cc & blower on, knob set to max cold: valve 11.82 (closed), pump .72 OK ;)

Just to confirm, the L shaped connector is for the valve and the flat connector is for the pump?

I've swapped a cc with no change. Any ideas what to check next? :confused: Thanks in advance!

Interior heat sensors.