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

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O2S - Test Notes and Schematic

Oxygen Sensor Harness Connector:






Enter this Pinpoint Test only when trouble code 15 or 17 is received in Quick Test steps 5 or 6, or when Quick Test step 11 directs you here.

This test is only intended to diagnose the O2S circuit.

NOTE: Code 15 indicates a continuously lean condition; code 17 indicates a continuously rich condition.