Failed Digital Heater Control Valve May Cause Poor Heat Output on Mercedes-Benz E320

A failed digital heater control valve can cause a lack of heat output from the climate control system.

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Average mileage: 72,250 (40,000–91,000)
3 model years affected: 2003, 2004, 2005
15 people reported this problem
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Viewing 1 - 7 of 7 problem details
This is a small cheap part that costs about $100 to replace. Try this - under the hood, on the left side of the vehicle (as you look forwards) there's a plastic cover over the bulkhead behind the brake reservoir. Give it a healthy slap. Try your heater.
2005 Mercedes-Benz E320 77,500 mi,
Climate control blows cold air only no hot air
My heater is blowing no heat just cool air...
2003 Mercedes-Benz E320 91,000 mi,
Cool Air but no hot air coming out.
2004 Mercedes-Benz E320 63,255 mi,
heater does not blow hot air only cold air
2004 Mercedes-Benz E320 40,000 mi,
had to change control system entirely.