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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Federal Vehicles



C.O. Potentiometer:





1. With the ignition "OFF", remove the electrical connector at the CO potentiometer.
2. Connect volt/ohm meter between terminal 1 and 3 of the CO potentiometer plug and measure the resistance.

^ The correct measurement should be approx. 0 to 2 ohms.

If the correct measurements are not obtained, the CO potentiometer is defective. Replace the CO potentiometer.