My 190 is blowing hot air constantly, while driving, blower not on, with all climate contols off. It seems the vent air is passing the heater coils. It does this on the R and L vents, the Windshield, and floor vent. The center vent doesn't do this. What could be the problem? This makes fore a sticky situation.

The vacuum line that goes under the battery tray could be burned through by battery acid. Also the heater valve line is in the same area. Could be also a bad fuse or valve.

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Benzmac:
ASE CERTIFIED MASTER AUTO TECHNICIAN
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