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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Heater Core Case: Testing and Inspection

Heater Relay / Test

There should be continuity between the 1 and 3 terminals when power and ground are connected to the 2 and 4 terminals, and there should be no continuity when power is disconnected.