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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DVOM Compatibility

ICM Input Tee:





ICM Output Tee:






CAUTION: A 12 volt rest Lamp should not be used to test CID, PIP, IDM, SPOUT or DPI circuit signals. It will load the circuit and may cause erroneous measurements or improper ICM/PCM operations (i.e. Engine stall).

NOTES:
^ When using a DVOM on the DC range, correct Test Lead Polarity must be followed. The red lead Is positive (+) and the black lead is negative (-).

^ To check PIP or CID, the engine is "bumped" with the starter without starting the engine while watching the voltmeter. Both the CID and PIP signals are digital and should switch between B+ and ground as the engine turns. To see the signal change using the DVOM, the engine must be turned in very short bursts.