Just got a p1646 code,linear O2 sensor control chip bank 1,any info on how I go about fixing this would be greatly appreciated guys,replace the thermostat today so I don't no if that may have upset something.

 

Graham11, I would like to be of help to you but I have ran into a snag.
First I have no idea what vehicle you are working on. You can go to the USER CP at the top of the page and add that info to your signature and it will always appear in your posts.
Second problem code P1646 if you have an early model XKR has nothing to do with O2 sensors. I have attached a copy of the DTC definition for that code.
If you have an XKR either your fuel pump relay has failed for the #2 pump or the #2 pump has failed. To track it down you can switch pump 1 relay with pump 2 relay and see if the vehicle will start. If it doesn't then the relay is definitely bad.


If you have anything other than an earrly XKR post the info and we can try again.

 

Thanks avern1,I own a 2001 xk8,thanks

 

Here's the extract from the Jaguar DTC listing for your MY:



ECM failure is unlikely so concentrate on harness or sensor fault.

Graham

 

Just had this fault myself. The heater on the O2 sensor had failed I think, that's the usual problem apparently. This was on my 2000 XKR. Replaced the O2 sensor and the fault has cleared.
Chris

 

Thanks guys,now we're is the O2 sensor on mine😕so I can replace it👍

 

It's in the upper part of the right side catalytic converter and can be reached from the engine compartment. There will be a DIY in the sticky or at jagrepair.com. Probably a u tube if you do a search.

 

JTIS (available for free download in General Tech Help) has all the answers.


(double click on the image to enlarge it)

Bank A is the RH side.

Graham

 

Sorry for being such a pain guys,ok I have ordered my sensor and I can see looking down into the engine compartment were the sensor fits ,next question,were is the plug in end of the sensor situated?also could you tell me were the relay is for this,thought I may just try a quick swap over as knowing my luck this just may be the problem, cheers guys👍

 

You'd likely also get a P1647 if it was the relay since it powers both heaters, but see this post by GGG for the location:
https://www.jaguarforums.com/forum/x...8/#post1775585


It is in the RHS false bulkhead on both LHD and RHD vehicles, despite what JTIS reports...

 

You haven't got to the 'pain' yet.

It's extraordinary just how tight the sensors can be. I've had to remove the cats before to be able to get to grips with the sensor on the bench.

Graham

 

Thanks for all your help guys,I will get stuck into this over the weekend and see how it goes👍

 

Ok guys just a quick update,I have now replaced each of my O2 upstream sensors yesterday with new sensors as i had the code p1646,now I get code p1646 and p1647 bank 1+2,when I clear the codes the engine warning light will go off for around 20 seconds then back on again,just wondering if I need to cover a certain amount of milage before it would reset itself,as I have only covered 2miles since the replacement ,if not what is my next step,any suggestions 😕

 

That means you haven't fixed it. Driving more wouldn't help.

Wrong kind of sensors? Bad wiring/fuses/relays/etc?

 

Be sure you didn't switch the plugs.