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:
^ The heater performance-the time to activity during a cold start
^ A slow response
^ The response time-the time to switch R/L or L/R
^ The inactive signal-the output should steady at a bias voltage of approximately 450 mV
^ A signal fixed high
^ A signal fixed low

Diagnose the Catalyst Monitor Heated Oxygen Sensors for the following functions:
^ The heater performance-the time to activity during a cold start
^ A signal fixed low during steady state conditions
^ An inactive sensor