Hi first time on here
my failed it mot on emissions and management light.
Plug my laptop in to get codes. It says O2 sensor fault and
Mil light off does anyone know how to turn it back on please.
Thanks

 

Hi Reelyp,

Firstly; welcome to the forum. ;-)

Do you have the exact code number as that will help pinpoint which HO2 sensor is faulty.
Our V6 engine have four HO2 sensors, an upstream and downstream sensor for each bank - front bank (Bank 2) rear bank (Bank 1).
So depending on what the actual reported code is (the HO2 codes generally range from P0131 to P0160) knowing that will help define which sensor and what type of failure the sensor has.

A failed sensor will generally bring up the MIL light, but once the sensor issue is resolved the MIL light will clear itself after a few short runs, or you can delete the error with a suitable OBD11 code reader.

 

Thanks for your reply. It's the upstream sensor on bank 1.
the management light did not come on at all.
On the diagnostic it says mil status off.
Thanks again.

 

Have never known a faulty 02 sensor not to put the mil light on.Has somebody disconnected it ? (which some dodgy types have been known to do when trying to get rid of a motor with issues.)
If you do replace sensors I would suggest you only use original ones to replace (Denso's).The X type is very sensitive to sensor readings.

 

+1 to Blues boy's comment on the sensor quality.
I started my reply while finishing up at work, and finished this when I got home and after walking the dog! So please excuse the continuity break.

Upstream Bank 1 sensor error codes will typically be P0131, P0132 or P0133 depending on the way the sensor is behaving.
The MIL light will only illuminate for these codes if the fault occurs in two successive trips.

Word of advice, get good quality sensors, plenty of rubbish sensors out there that may let you down not long after fitting.
If you are doing the job yourself, you would be advised to pick up a HO2 sensor removal socket.
There are plenty of threads written about sensor replacement, but when I replaced my upper Bank 1 sensor I found it easiest to remove the intake manifold and work from the top (bearing in mind my X-Type is FWD not AWD, so find some videos or read some threads to help you make a plan.

 

I planned anyway to write about the fun I had a few days ago with my upper bank 1 O2 sensor, X-Type, and since this seems to be your issue at hand, I just typed it in:
https://www.jaguarforums.com/forum/x...8/#post2647034

 

For those not in UK, they're tested by a probe in the exhaust measuring the actual exhaust gas.

OK, so definitely needs fixing once diagnosed.

About the MIL - was it on or does it not self-test?

Fix the sensor

You want the MIL off. (The actual MIL also must self-test of course.)

Codes stay stored harmlessly when the cause is fixed (or has gone away, not so commonly). They won't cause MOT fail if the actual MIL is off (& self-tests).

They are stored like that so that a customer arriving with MIL off but describes their recent problem isn't presenting a car which is no help.

The stored codes with MIL off - fairly common and not an MOT fail.

Codes which flagged and put the MIL on can turn into the above (codes stored but MIL off) if the cause goes away for several successive (4) warm ups. They are eventually deleted (40 or 80 warm ups).

I'd change the sensor then use the car a bit then use OBD live data to check the fuel trims (read the forum for info).