I have a new sensor but I'm not confident that the wires are right.
my car has green, brown, red with white strip,and white with red strip.
but my sensor has 2 black 1 blue 1 white .
What colour goes to what ?

 

This may help a little bit: If I am not mistaken, you should be able to measure a resistance of between approx. 3 - 11 Ohm between your 2 black wires. (if not, then your old O2-sensor is really buggered), But at least you can compare, which 2 wires you have at the positions of those 2 black wires on your new sensor, and there you should be able to measure something between 3-11 Ohm then. It that is correct, you would know at least that those 2 wires are in the correct position and this should give you a bit of confidence. Other than that I assume that you bought an O2-sensor, which is suitable for your S-Type?!

 

If it's the right kind of Denso wideband sensor it should just work. If not I would get one.

 

Very hard to fit but went in eventually, not the wiring or the sensor so it's the ecu . Thanks for the input guys.

 

Whoa! Slow down!

A failure of the PCM is extremely rare. What symptoms are you seeing that led you to replace the O2 sensor? Did the symptoms change with the new sensor?

Did your new sensor include the connector end? Or did it require swapping the new wires into the old connector? Reading between the lines, it seems like the latter. Some bargain brand sensors come like that, and I wouldn't trust them one bit.

Also, the wire colors on the sensor itself are immaterial. A manufacturer might use whatever color they wanted, so you can't go by that. The only thing that matters is which wire goes where.

Considering you asked about the wire colors, apparently no instructions were included. That leads to a strong possibility of a mixup during assembly. That's why I asked if the symptoms changed.

 

No the fault still comes up with the new sensor .
I checked the sensor and got readings and the wires to the ecu all check through ok. I've canceled the fault but still comes up and the fuel consumed is much higher than it was.

 

The problem I had with the new sensor was that the original socket was very hard to push on to the new sensor plug and as it's so hard for me to get to its location. The new sensor comes from a good dealer here in New Zealand in a Jaguar box. It cost a lot more than the cheap ones.

 

And the exact fault is?...

Not trying to bust your butt. More details will really help. Are you getting a five digit OBD fault code?

Even if an O2 sensor is the most common root cause for a specific fault code, there are other possibilities. An exhaust leak is one example that comes to mind, and there are many others.

Also, make sure you are using Jaguar's official code definitions, found here:

JagRepair.com - Jaguar Repair Information Resource

Many scanners give generic definitions that can lead you in the wrong direction.

 

Hi yes its the p1647 I think. It's wet outside so not going to check !

 

"HO2 Sensor 2/1 heater failure
HO2 Sensor 2/1 sensing circuit: short circuit to ground,
short circuit to high voltage, open circuit, high resistance"

All of those come before the ECM on the troubleshooting list for your P1647 DTC.

You said that the connecter was difficult to seat; did you check and straighten any bent pins prior to pushing the sensor's side home?

 

+1

Also there are pinpoint tests for the wiring etc.

It really is staggeringly unlikely to be the PCM ("ecu" - but there are 10-20 of those).

 

Service manual here:

http://jagrepair.com/images/AutoRepa...M-Workshop.pdf

Do a control-F search for P1647 and you will see the pinpoint tests for this fault.

Are you positive you have the correct location? P1647 is for the upstream sensor on the left side, viewed facing forward.

You mentioned the connector was difficult to seat. I'd certainly want to make sure this problem is not caused by a marginal connection there.

And WAY before even considering the PCM, I'd want to swap the two upstream sensors and see if the fault follows. There's no guarantee your new sensor is good, even though it's new.

 

I will do further test then before I go forward with other plans.
thanks for all the help and I will test all the pins as advised and let you know the outcome . Have to leave it now untill Monday unfortunately 😑.
definitely the right sensor .