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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15-Step D, Logic Module Ground Circuit


1. With ignition switch in the RUN position, connect a suitable digital voltmeter between terminal No. 23 of the logic module white electrical connector and ground.
2. If voltmeter indicates 7 1/2 to 9 volts, proceed to Test 15 step E.
3. If voltmeter indicates 0 volts, proceed to Test 15 step F.