Ime getting to the stage of trading in the car for an mx5!!!!
I keep getting an intermittent fault 1647 1646 which is bank one and bank 2 o2 sensor open / shorted. Resulting in engine safe mode no acs no trac control.
i can’t believe both sensors would fail at the same time is there a common connection block for both banks ?
or is the ecm suspect
any one that can help would be appreciated
its a 2000 Xkr
shaun

 

Shaun,

These codes relate to the HO2S heater. In addition to failure of the sensors themselves, it can be circuit faults. Here's the relevant extract from the Jaguar DTC list:



I agree that concurrent failure of both sensors is unlikely as is the possibility of ECM failure. If this had happened, you would have many other fault codes stored.

If the circuits check out satisfactorily, a failing battery can often be the cause of otherwise unexplained DTC's.

Graham

 

Thank you for the input graham. I agree with the battery , first thing I did was buy a new battery £120 well spent I thought if it works . Sadly not though

 

So trace the wiring etc as per the workshop manual (free download).

 

Fair enough so I have! The only common connection is on a dotted line at a splice ems8
Raises 2querries what is signified by a dotted line and can anyone direct me to the whereabouts of the splice ems8
Shaun

 

I had a look to to refresh my memory.

The other common factor is the HOS2 heater relay in the engine compartment RH side bulkhead extension box. Could explain both sensors setting a fault.



It's one of the many brown relays on the vehicle so easy to find another to swap as a test.

Graham

 

Nice one graham that has to be likely
Thank you

 

Drat !!!!
I don't seem to have a heater relay there is only the 3 in line relays

 

 

You might want to double check the later year circuit diagram. From memory, that relay is not clearly documented, but there are clues in the later diagram to sort this out. I am talking about the diagram that shows an outline of the car with all the relay locations. Separately, I believe the RHD and LHD cars have differences.

 

The Electrical Guide for RHD 2000 MY claims it's the fourth one there ........


(click on the image to enlarge it)

....... but there's no denying the photographic evidence!

Graham

 

Thought this rang a bell. The O2S relay is located in the position shown on Graham's diagram for LHD cars, irrespective of where the steering wheel is located. For RHD vehicles, it's adjacent to the brake master cylinder reservoir:

 

Ye gods!!

Hopefully saxplayer will finally have a chance!

 

Hi guys last call for help!
Thank you so far for the advice but ime no further in solving the problem . The wiring diagrams show a relay for the heater however ime not sure there is one for my engine . I have pulled them out individually to simulate the fault but no effect the only one is the ecm relay
All the diagrams I have downloaded are xk8 I am presuming they are the same for xkr the car is a 2000

 

Hi Sax,
Can you post a shot of your RHS engine enclosure?

The 'R also has the intercooler pump relay on that side. The wire colours to the HO2S relay should be: White/Blue, White/Green (2) and Black which would confirm it once and for all.

 

Hi Michael

 

OK.

First picture is starter relay.

Second picture:

Your middle finger is on the HO2S relay, index finger on intercooler pump relay.

Hope this helps,
Mike

 

Thank you mike