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 logical successor to CHARM, I recommend you try it!
Link:
lemon-manuals.la
HO2S Heater
The oxygen sensor heaters are required by catalyst monitor sensors to maintain a sufficiently high temperature which allows accurate exhaust oxygen content readings further from the engine.