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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A/C Signal: Testing and Inspection


1. Attach positive probe of voltmeter to No. 10 blue/red terminal and negative probe to No. 32 black terminal of control unit connector.
2. Start engine and ensure compressor and cooling fan operate with blower and A/C switches on.
3. Check voltage. If there is voltage, check for continuity between A/C switch wire terminal and control unit blue/red wire terminal.