Error Code Help.

[Guest Dave-C4]

Evening guys,

 

I'm new here, so firstly, hello! I don't own a C4 myself, but my dad does, and he's having a spot of bother with it. I'd appreciate you help if you could?

 

The EML comes on and when using a fault code reader, it comes up with a code of P0138, which from what I have read is "Rear Heated Oxygen Sensor High Voltage" And I believe this fault code appears when the heated oxygen sensor voltage is more than 1.2V. Now, is anyone aware of this fault? Have you come across it before? I've reset the light a few times now, but it comes back on within the same day, normally within an hour or two. If this is a known fault, could anyone advise what the fault was? Is it as simple as a new 02 sensor is needed? If so, is there any recommended and competitive places on the internet to buy one?

 

Sorry that my first post is a question, but I really want to help my dad out.

 

Thanks,

 

Dave.

 

P.S. Does anyone know which pins I need to measure across to measure the voltage with a multi meter?