Morning everyone,

Full story - driving home yesterday afternoon EML comes on, read the code - P1646 - Lambda sensor out - fair enough I think, bit annoying but not exactly unexpected on this car. If it helps, fault code shaded yellow.

This morning, turn car on, rear window a bit wet so turn heater on....nothing, only then that I realise the AC/climate is out, and the touchscreen is on the main menu and unresponsive to touch, clock is out (showing --:--) as is outside/climate temperature LCD screen. EML warning for P1646 now shaded red on my OBDII app.

Clearing the code within app brings everything back up and working, so there's not a problem with the console (as far as I can see) but yellow fault code reoccurs on engine shutdown and restart.

Would a lambda sensor really knock all of that stuff out? Or should I be looking for an electronics issue somewhere?

Thanks for your time.

 

I can't imagine a lamba sensor knocking out the power. I would be looking at load testing the battery. Removing and cleaning the battery cable connectors and also check the cables for signs off corrosion. It sounds like a loss of voltage.

 

Brilliant, thanks, I'll start there.

 

Bad battery, cabling, fuse blown, ...

Not caused by the O2 sensor, I suspect, but might be a common thing somewhere among that lot to explain all.

 

Thanks, my suspicion too.

I'm guessing not the fuse though as clearing the ECU codes brought it back online instantly?