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17511 - P1103 - O2 Sensor Circuit Heating Circuit (B1-S1) - Output Too Low

No ECU light. Just pulled it up on a random checkup.

Any ideas?

Cheers

Well if the description is correct, it means that the lambda sensor that is mounted on the exhaust MANU-CAT has a failing heater. I'd expect that eventually it will fail and bring the warning indicator. This sensor controls the mixture - and the B1 S2 one monitors the second cat output - so this failing or faulty heater will just be slowing down the time it takes for this first sensor to get up to operating temperature. This might not cause real problems for a long time I'd guess - or maybe this was a "spurious" fault - so check it again soon to see if its still getting logged as a fault.

Thanks for the clarification RUM4MO. Have cleared it for now, but will keep an eye on things.