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)

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Coolant Temperature Sensor/Switch (For Computer): Service and Repair


This procedure should be performed only on a cold or cool engine.
1. Disconnect battery ground cable.
2. Disconnect electrical connectors from coolant temperature sensor.
3. Remove sensor from engine.
4. Reverse procedure to install.