Operation CHARM: Car repair manuals for everyone.
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Signal Too Low. Intermittent Fault





Checking Cables And Terminals
- Check cable between heated oxygen sensor (HO2S) terminal 1 and main relay (2/32) terminal 3 for an intermittent open-circuit.
- Check cable between heated oxygen sensor terminal 2 and engine control module (ECM) # A14 for an intermittent short-circuit to ground and an intermittent open-circuit.
- Check heated oxygen sensor and engine control module connectors for loose connections and contact resistance and oxidation.

CAUTION: Do not apply rust solvent spray or grease to the heated oxygen sensor connector.

- Proceed to: Fault-tracing Information section below.

Fault-tracing Information
For intermittent faults fault-tracing is not followed by a verification because the fault is not present at this moment.

- Do you want to repeat fault-tracing?

Yes:
^ Proceed to: Checking Cables And Terminals section above.

No:
^ Operation done.