Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

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Air Door Vacuum Motor Test



1. Verify that the air door is in the closed to heated air position and that the vacuum motor stem and the air door are connected, by looking up into the snorkel.

2. Remove vacuum hose from motor, connect a vacuum pump, and apply 10-15" vacuum.
Air door should be in the open to heated air position and must remain so for two minutes with vacuum trapped. When vacuum is released the door should move to the closed to heated air position.