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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Function Test

Function Test:




Before beginning the functional test of the heater system, ensure that the vehicle is idling with the coolant hot and the thermostat open. Ensure that the coolant temperature is 90°C (194°F). Even if a problem is found during any intermediate step of the functional test, complete the test before the repair begins.