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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Oxygen Sensor Diagnosis

Diagnose the fuel control heated oxygen sensors for the following conditions:
^ Heater performance, time to activity on cold start
^ Slow response
^ Response time, time to switch R/L or L/R
^ Inactive signal, output steady at bias voltage - approximately 450 mV
^ Signal fixed high
^ Signal fixed low

Diagnose the catalyst monitor heated oxygen sensors for the following functions:
^ Heater performance, time to activity on cold start
^ Signal fixed low during steady state conditions
^ Inactive sensor