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
If it fails: lemon-manuals.org.ua

Or, hide this message: temporarily or permanently

On-Vehicle Inspection




1. Install manifold gauge set.
2. Run engine at fast idle.

3. Check compressor for following:
1. High pressure gauge reading is not low and low pressure gauge reading is not higher than normal.
2. Metallic sound.
3. Leakage from shaft seal.
If any of the above checks indicates a defect, repair compressor.