My 2003 XKR has a DTC code P0057 HO2S Heater Control Circuit Low Bank 2 Sensor 2

Everywhere I have read online this is the downstream (after the catalytic convertor) sensor on the left hand side of the car (drivers side, NA), and is the lower of the two sensors. I ordered a Denso 2344798 to replace it, and started to fit it this morning.

This morning I started to remove that sensor. I had expected that to be a challenge, but it was pretty easy to loosen and I didn't need to cut the cable, so I was about to unplug it under the hood.

However, I couldn't find exactly where the connector was under the hood, so I took a look at JTIS - and found this diagram showing the O2 sensor locations (I have also attached that entire section from JTIS)

This diagram clearly shows the heated O2 sensor (HOS2) is the UPPER sensor, #1 in the diagram. I have loosened the lower one, #2 in the diagram.

So - before I go any further, given that I have code P0057, which sensor should I be replacing - and did I buy the correct replacement?

Thanks in advance!

-Steve


2003 XKR O2 Sensor locations from JTIS

 

I think you got it right, driver side, lower sensor. To my knowledge, all 4 sensors are heated. Upstream are wide band, downstream are narrow band. Definitely different type, different part#.

The connectors are all behind the throttle body, sort of on top of the transmission.

As per eBay, part# seems right.

 

Thanks - yes. The description of P0057 seems to vary.

If you search JTIS for P0057, it comes up with the following, which is far clearer - "DTC P0057, P0058; LEFT-HAND CATALYST MONITOR SENSOR HEATER CONTROL CIRCUIT LOW/HIGH RESISTANCE". That description of it as the catalyst monitor matches the diagram, so I decided to go with it. Kind of confusing that the lower sensors have different names in different places...

Fitted the Denso,and just got back from a test drive. No current or pending code, so fingers crossed that has sorted the problem...

-Steve

 

Hopefully so, but it's a 2-trip code (see Jaguar doc) i.e. needs 2 warm ups before it would flag if it's going to do so.