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)

Or, hide this message: temporarily or permanently

Idle Up Control Valve: Testing and Inspection

Air Control Valve Circuit:





Air Control Valve Inspection - Checking Resistance:





Inspect ACV For Open Circuit
- Using an ohmmeter, check that there is continuity between the terminals.

Resistance (Cold): 30 - 33 ohms at 20°C (68°F)

- If there is no continuity, replace the ACV.


Air Control Valve Inspection - Checking For Short:





Inspect ACV For Ground
- Using an ohmmeter, check that there is no continuity between each terminal and the body.
- If there is continuity, replace the ACV.


Air Control Valve Inspection - Checking Operation:





Inspect ACV Operation
- Check that air does not flow from port E to F.





- Apply battery voltage across the terminals. Check that air flows from port E to F.
- If operation is not as specified, replace the ACV.