HVAC Air Flow Switching to Defrost When Accelerating on Dodge Ram 3500 Van

Problem overview

The AC/heater (HVAC) system may unexpectedly switch to the defrost mode when accelerating. This system is operated by engine vacuum and should be inspected for any vacuum leaks if this problem develops. There is also a revised vacuum check valve available to address this concern.

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HVAC Air Flow Switching to Defrost When Accelerating on Dodge Ram 3500 Van

Problem overview

Dodge Ram 3500 Van vehicles with this problem

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HVAC Air Flow Switching to Defrost When Accelerating on Dodge Ram 3500 Van

Problem overview

Dodge Ram 3500 Van vehicles with this problem

Repairs related to this problem

AC Diagnosis

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