I'm not sure, but it sounds to me you have a distribution on the system. A few years ago my whole dash lit up because my power steering pump (electric power steering pump, not belt driven) was on the way out, which messed up the whole line of electronics. Replaced the pump and problem went away. But ...

Sooo hold up they will re baseline the ecu/ECM based off not stock but the condition of our now 10 year old cars? This is logical. But did you have the dealer do this with the O2 sensor spacer? What O2 sensor spacer did you buy ? And how was this service free? Nothing from Volvo is free.

Bit of ...

I have the exact same car with the exact same code, is this still cleared for you? if you search this code for other P3 Volvos you can see this can be a hole of a problem.

when you take the A-pillar covers off the dashboard just moves up and out. just like the post instructions

I don't wanna be the guy that says it's not possible, but I don't think it's possible. Maybe if you have small diameter forearms. But even then the kick plate has to go, and probably have to move the harnesses from the cem.

Where are you guys buying the OEM cats? From Volvo directly? Or is there a cheaper alternative that will make the codes go away

The downstream, #2, sensor is the one checking catalyst. If it more or less mimics the front one then the catalyst is not working. If the front goes below 1, to something like .97 and the rear goes up to .8V and then when the front goes over 1 to something like 1.04 and the rear goes to .1V and it ...

Actually immediately after I made that previous post, the car rumbled and the second sensor went to 0v and I threw another communication code. So I revved the motor to see what would happen and I got a reading from the second sensor. First image is the revving.

Great information man, thank you so much. But interesting enough before the leak test the voltage in sensor 2 was bouncing all over the place. The test went as you said it would things stabilized quick and even the second sensor went where it was suppose to, then started bouncing like crazy. Anyways ...

Good afternoon everyone

So my Volvo is back at it. (Please see attachment) little back story, I just got over a knarly problem in the car that had to do with the network, and it ended up being the electric power steering pump (thanks again Paul) but now I have this, and as I'm sure you'll notice I ...