Function Knob For Heat/Cool
Van Man
06-10-2004, 06:30 PM
Hello,
Well here is the first problem I've encountered with my new (used) 97 GMC Safari van. The function knob seems to be stuck on defrost. I can turn the knob just fine but the direction of the air doesn't change. Any body have any ideas? Also can someone steer me to the best repair manual available for my van. I hope to be able to fix most of the problems myself.
Thanks,
Van Man
Well here is the first problem I've encountered with my new (used) 97 GMC Safari van. The function knob seems to be stuck on defrost. I can turn the knob just fine but the direction of the air doesn't change. Any body have any ideas? Also can someone steer me to the best repair manual available for my van. I hope to be able to fix most of the problems myself.
Thanks,
Van Man
GMCTech
06-12-2004, 12:33 AM
The most common problem causin this concern is a broken vacuum line.
There is a stiff plastic vacuum line that runs from the firewall to the vacuum canister across the top of the intake manifold. It gets hot and brittle and ends up breaking above the intake most times.
Follow that line - you should find a break or crack somewhere.
Hope this helps.
There is a stiff plastic vacuum line that runs from the firewall to the vacuum canister across the top of the intake manifold. It gets hot and brittle and ends up breaking above the intake most times.
Follow that line - you should find a break or crack somewhere.
Hope this helps.
Automotive Network, Inc., Copyright ©2026