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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

The control module diagnoses the fuel control heated oxygen sensors for the following conditions:
^ Heater Performance (time to activity on cold start).
^ Slow Response.
^ Insufficient Switching.
^ Transition Time Ratio.
^ Inactive Sensor (output steady at bias voltage - approximately 450 mV).
^ Signal Fixed High.
^ Signal Fixed Low.

The control module diagnoses the three-way catalyst monitor heated oxygen sensors for the following conditions:
^ Heater Performance (time to activity on cold start).
^ Signal Fixed High.
^ Signal Fixed Low.
^ Inactive Sensor.