Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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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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Test H: Fuel Control

Compuvalve Circuit Data Sheet:





02S Voltage Specification:






H1 - H4:





H5 - H7:





H10 - H13:






This pinpoint test is intended to diagnose:
- HO2S
- HO2S connections
- Vacuum systems
- Compuvalve
- Harness circuits: HO2S and VPWR

CAUTION: Probing or piercing wiring insulation is not permitted and may allow water entry, causing corrosion and shorting which may result in HO2S failure.