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)

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Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection

- disconnect thermoswitch harness connector from thermoswitch and measure resistance between terminals of switch

Checking specification if switch temperature is:
below 20°C (68°F) = Zero ohms (continuity)
over 40°C (104°F) = Infinite ohms (open)

If an acceptable value is NOT obtained
- replace thermoswitch

If an acceptable value is obtained
- check for open circuit using wiring diagram