UK-POLOS.NET - THE VW Polo Forum

After replacing battery engine light came on, error codes for both lambda sensors. Replaced the sensors for new ones from eurocarparts, got the error codes reset at local garage however the light has come back on. Anyone got any ideas on this one.

So, why did you replace the battery, also why did you replace these sensors, was the car scanned using a proper VW Group compliant scan tool and that revealed lambda sensor fault codes - but which ones for which lambda sensor?

It has been written many times in the past that buying cheaper replacement sensors sometimes is not the best plan, VW Group tend to only fit NTK sensors at the factories - that is an NGK brand covering Lambda sensors and some others.

I hope that you have not thrown the original sensors away!

Maybe find out which fuse(s) cover these lambda sensors heaters and see if it/they are still okay, having a proper record of what the initial scan reported is critical to resolving this quickly now.

Changed battery as it kept going flat. Local garage reset codes and just said it was for front and rear sensors but did not tell me codes. Have kept old sensors as well and soaked in petrol overnight in case have to put back in.

Error codes off scanner are p0031 and p0037. Seems to signify low voltage on sensors. So same error codes coming up for old and new replacement sensors. So I am thinking there is a fault on either the ground or 12V to sensors, possibly blown fuse on 12V feed. Anyone know which fuse? Or any other thoughts.

news on solving the problem?

I get the impression, that that member, joined>asked for help>left as "he" joined at the time the first question was asked and has only posted 3 times and always on the same topic/thread.

But I could be wrong though!

Everyone should close down any "help" threads they start with a conclusion, most members do, but others -----------.

Problem was solved, found fault was a blown fuse.

Thanks

Could u explain what fuse was blown? I cant find the the fuse location for the 02 sensor on my 9n3. Would anyone be able to help, i have error codes p0031 and p00037, wanted to check fuse before changing sensor