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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Refrigerant Pressure Sensor / Switch: Testing and Inspection

1. Connect a suitable refrigerant pressure gauge to high pressure port of A/C system.
2. Connect continuity tester to A/C system high pressure switch terminals.
3. Start engine and engage A/C system.
4. Observe A/C pressure gauge and continuity tester. Circuit should close when pressure rises above 205-252 psi.
5. Circuit should open when pressure drops below 170-218 psi.