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

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.

RepairPal Verified
Average mileage: 163,000 (120,000–206,000)
8 model years affected: 1995, 1996, 1997, 1998, more1999, 2000, 2001, 2002
10 people reported this problem
The nation’s largest network of independent repair shops certified for expert training, quality work and fair pricing
Viewing
1
-
1
of
1
problem details
1995 Dodge Ram Wagon 3500 206,000 mi,
Based on how fast the van is going the air from the vents switches to defrost and heat vents.