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Hi Steve,
The chart came from the 2001 MY electrical diagram from JTIS. I've checked the 2000 in case yours was a late build, and they concur.
Even the 1999 shows the relay in the same place, with the note 'AJ27 only'. Oddly, the arrangement in your pic is the same as mine - but that's a 98 (AJ26).
JTIS does contain some errors, but I haven't seen this come up before.
Hi Steve,
The chart came from the 2001 MY electrical diagram from JTIS. I've checked the 2000 in case yours was a late build, and they concur.
Even the 1999 shows the relay in the same place, with the note 'AJ27 only'. Oddly, the arrangement in your pic is the same as mine - but that's a 98 (AJ26).
JTIS does contain some errors, but I haven't seen this come up before.
Confused. I'll try a little more research...
Mike
where is the vin no on the vehicle? I've got the no on the v5 and that is correct for the car. I'd like to find it on the vehicle as well I've got no reasons to think it's wrong at all but as you say it's strange that the configuration is not as expected.
Cheers
Hi Steve,
VIN is on the dash behind the bottom LHS of the windscreen, and also (unless the sticker has gone) on the LHS door jamb. I believe it's also marked on the boot floor somewhere.
Curious. I've been searching for a possible alternative location for the relay, but nada.
Hi Steve,
VIN is on the dash behind the bottom LHS of the windscreen, and also (unless the sticker has gone) on the LHS door jamb. I believe it's also marked on the boot floor somewhere.
Curious. I've been searching for a possible alternative location for the relay, but nada.
I don't know about access on the car in question but on my STR it's easy enough to get to the actual sensor, disconnect it and meter the heater (on mine, the two black wires). Comparing the two banks can help but I think mine was about 1 ohm when cold. I had a bad one that threw the code you have and it was open circuit so clearly blown.
I don't know about access on the car in question but on my STR it's easy enough to get to the actual sensor, disconnect it and meter the heater (on mine, the two black wires). Comparing the two banks can help but I think mine was about 1 ohm when cold. I had a bad one that threw the code you have and it was open circuit so clearly blown.
The code reader says the circuit is shorted/open. I assume that you mean that using a multi meter on ohms to detect the presence of a viable circuit, showed a good circuit on one bank and no result on the failed one?
Any knowledge of where the sensors are on the XK8 would be helpful. I have the testers so I can deal with that side of things.
Hi Steve,
Yes, it's good. It's also good that your CVVT actuator seals aren't leaking oil as they're prone to doing. Motor looks well cared for too, although I do see upper front shock mounts in your future, unless it's the angle of the photo.
I can't find anything that shows that relay anywhere else than on the chart above, but I've been caught out before with JTIS and component locations. Hopefully someone with a 2001 will chime in here and advise.
Are you now only seeing the P1647? If so, I'd suggest doing some multimeter checks on the sensor as JagV8 recommends. The heater element is what usually fails from what I've read.
FWIW, if you look at the Electrical Guide for MY 2003, the relay(s) for the O2 sensors (there are 2 of them in the later car) have moved to the other side for a RHD car. Maybe you can provide a picture of that UK driver side relay box for comparison. Just a shot in the dark, really.
Separately, even if the grouping of the relays in the Guide suggest differently, maybe the top most relay in the picture above IS the O2 relay. One way to know would be to check the wire color underneath it and cross reference with the Guide.
Separately, there is probably so much time you want to dedicate to this hunt. More than likely, the sensor heating circuit is broken, and you need a new sensor. They are not super expensive, and you can rationalize the purchase by convincing yourself that the purchase price will be offset by savings in gas over time. FWIW, on a later car, that sensor was reachable from the top with a crows-foot O2 socket. It was maybe an hour-long fix as the intake pipe has to come off and the wiring has to be properly routed.
FWIW, if you look at the Electrical Guide for MY 2003, the relay(s) for the O2 sensors (there are 2 of them in the later car) have moved to the other side for a RHD car. Maybe you can provide a picture of that UK driver side relay box for comparison. Just a shot in the dark, really.
Separately, even if the grouping of the relays in the Guide suggest differently, maybe the top most relay in the picture above IS the O2 relay. One way to know would be to check the wire color underneath it and cross reference with the Guide.
Separately, there is probably so much time you want to dedicate to this hunt. More than likely, the sensor heating circuit is broken, and you need a new sensor. They are not super expensive, and you can rationalize the purchase by convincing yourself that the purchase price will be offset by savings in gas over time. FWIW, on a later car, that sensor was reachable from the top with a crows-foot O2 socket. It was maybe an hour-long fix as the intake pipe has to come off and the wiring has to be properly routed.
Best of luck, keep us posted.
ive attached the picture of the relays on the drivers side. I'm inclined to agree that if it looks like a duck, walks like a duck and sounds like a duck it's probably a duck so the sensor might be favourite! It's this forums fault for filling my head with nonsense about not believing the diagnostics could actually be telling the truth. Lol.
Best guess is that the brown relay near the top of your picture, near the brake fluid reservoir is the O2 heater relay. Nothing I see in the Guide suggest anything else. It is either for LHD cars, or the XKR inter-cooler pump relay (n/a for an XK8).
The thing is that this same diagnostic code can have multiple causes. The relay/fuse are a good place to start because they are easy to replace and cheap to buy.
Steve,
fmertz is on the right track. I did see the RHS location on the 2003 diagram and dismissed it.
JTIS shows the relay on the top right of your pic as the O2S heater one for LHD vehicles, although not quite in that place. Jaguar obviously decided it was a picturesque location and thus kept it there regardless of driver orientation.
Wire colours to the relay should be: White/Blue, White/Green (2) and Black which would confirm it once and for all. Amazed this hasn't cropped up before: I guess because the majority of members drive LHD cars.
Your next mission, should you choose to accept it, is to find connectors EM1, 2 & 3 from the location given by JTIS. (Just kidding)
Best guess is that the brown relay near the top of your picture, near the brake fluid reservoir is the O2 heater relay. Nothing I see in the Guide suggest anything else. It is either for LHD cars, or the XKR inter-cooler pump relay (n/a for an XK8).
The thing is that this same diagnostic code can have multiple causes. The relay/fuse are a good place to start because they are easy to replace and cheap to buy.
Best of luck, let us know what you find out.
ill check it in the morning. So if the relay is in a completely different place is the correct fuse still on the passenger side where we were looking for the relay before?
Steve,
fmertz is on the right track. I did see the RHS location on the 2003 diagram and dismissed it.
JTIS shows the relay on the top right of your pic as the O2S heater one for LHD vehicles, although not quite in that place. Jaguar obviously decided it was a picturesque location and thus kept it there regardless of driver orientation.
Wire colours to the relay should be: White/Blue, White/Green (2) and Black which would confirm it once and for all. Amazed this hasn't cropped up before: I guess because the majority of members drive LHD cars.
Your next mission, should you choose to accept it, is to find connectors EM1, 2 & 3 from the location given by JTIS. (Just kidding)
Probably still the sensor.
Happy hunting,
Mike
ill check the wiring colours in the morning. If it's taking me this much effort to find a relay I've got no chance with connectors em1 etc lol
Thanks.
Last edited by Chalgravesteve; Mar 10, 2017 at 04:23 PM.
Steve,
fmertz is on the right track. I did see the RHS location on the 2003 diagram and dismissed it.
JTIS shows the relay on the top right of your pic as the O2S heater one for LHD vehicles, although not quite in that place. Jaguar obviously decided it was a picturesque location and thus kept it there regardless of driver orientation.
Wire colours to the relay should be: White/Blue, White/Green (2) and Black which would confirm it once and for all. Amazed this hasn't cropped up before: I guess because the majority of members drive LHD cars.
Your next mission, should you choose to accept it, is to find connectors EM1, 2 & 3 from the location given by JTIS. (Just kidding)
Probably still the sensor.
Happy hunting,
Mike
correct!! 2x white/green a black and a white with a blue dot! I'll get a new relay and change that.
It probably is the sensor and on my STR it's OK access so unplugged while under the car, checked ohms with meter, open circuit so replaced sensor and all fixed.
My sensor didn't want to come out but as it was dead and I didn't have the special socket I cut the wires off and used a normal socket.
Just got the car back from its service and MOT, I had the timing belts checked (2nd generation plastic) and changed to metal tensioners. New metal water pump as well. Pinhole leak in a rad pipe and they changed the sensor for me as well.
Looking forward to a few trips out in the car now the sun is out!!
Luckily clearing the codes worked for me! Got the check engine MIL and code P1646 (ECM HO2S control malfunction A bank upstream) last week after the car had been sitting for about a week. Cleared the codes with OBD reader and the engine light hasn't come back on and the car is running beautifully. Glad I thought to reset the codes before tearing everything apart! Fingers crossed!
MY 2000 XK8
