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.