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

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Fuel Tank Unit: Testing and Inspection

Fuel Tank Sending Unit Test

With the ohmmeter positive lead on the signal wire lead and the negative lead on ground, check the resistance values of the fuel sending unit at various positions of the float arm. An open circuit will indicate infinity on the ohmmeter and a short will indicate zero ohms.