Hi folks, just bought my first Jaguar. It's an '89 V12 convertible. It has some issues and opening the hood is pretty scary, but hopefully I can adapt to the British engineering. I've only put 100 miles on the car since buying, so I'm still not real familiar with the car.

1.  
   1. Temperature gauge indicates overheating @ highway speeds. I've read some typical issues and will implement them soon, such as bleeding air out and checking belt tension/condition for water pump.
   2. Cruise control does not work. All fuses under dash are ok.
   3. Horn does not work. All fuses under dash are ok.
   4. Passenger window does not operate well and gets stuck all the way down and midway. Window motor does not cut out in up or down position. I need to know how to remove the door panel, specifically the inside door handle. It seems to be bolted into the door frame.
   5. I'm missing the front air dam/spoiler. I'm looking to buy one. I understand this could help attribute to the overheating issue.

Thanks in advance and I really enjoy reading all the threads.

 

Welcome to Jaguar ownership !

1. This one would be worrying me, as overheating a V12 is fatal. Let's just hope it is the guage...
2. Neither does mine.... I've narrowed it down to the vacuum pump not working, but I can't find a suitablly cheap replacement yet
3. Don't know, sorry
4. Clean the switches in the centre console (pry them out with a screwdriver, then take them apart and clean all of the contacts for starters). To remove the door trim there are 4 screws. First screw is visible at the front of the door and holds the chrome check plate in place. 2nd and 3rd screws are visible underneath the door pocket. 4th screw is hidden underneath the chrome bezel at the end of the arm rest where it joins the door. I do not have a good way to prise this bezel back to gain access to the screw... everytime I do it I end up marking the leather on the arm rest, but as I've redone the whole interior with leather mender anyway, I can touch it up, but it's still a pain
5. Mine was missing too, and I bought a replacement one from SNG Barratt (Part Number BEC13168) which looks great, but it made no difference at all to engine temperature so I'm not sure I would buy one if you were hoping to reduce the engine temp

You may also try jaglovers.org and roadfly forums for XJS advice. This board is excellent for the more modern cars (I have a '00 XJR and well as an XJS) and I get all the info I need on the XJR here, but not so the XJS

 

This should help with the cruise control
http://www.jag-lovers.org/books/xj-s/16-Cruise.html

This might help with the horns. It was written for the XJ6 but the circuit should be the same even if component locations are different
http://www.jag-lovers.org/xjlovers/xjfaq/horn.htm

Get that radiator hauled out and professionally cleaned, pronto ! Check your fan clutch as well, just for the heck of it. People will often say the fan flat-out isn't needed at highway speeds. My experience is just the opposite.


Another possibility on the window is that the felt channel is falling apart and jamming the glass. Or, sometimes, the channel just needs a healthy dose of silicone spray.

Cheers
DD

 

Thanks for the help! The links did the trick.
I bought an infrared thermometer to help diagnose the water temperature.

 

Yikes! I pulled the radiator to have it rodded out, but it was clean. The T-stats seem to work as they should. Before pulling the radiator,
I fabricated a front spoiler and I sealed around the radiator with foam.
The clutch on the fan seems to have enough resistance, but I'm thinking of trying to lock it up to be sure. Any other ideas?

 

The fan clutch maybe locked up and that would cause over heating at highway speeds. The clutch should freewheel once you are up that fast. A locked fan clutch will actually slow the fan down and reduce the air flow.

 

I replaced the thermostats and fan switch with lower temp ones in my car (though they will not help at highway speeds). If the radiator capillary tubes look clean, I still wonder what the bottom of the radiator looks like. Sediment that may accumulate at the bottom will reduce the volume of coolant flowing through the radiator, thus increasing the temp. I would replace the thermostats anyway. Try adding a cooling agent like Water Wetter (by Red Line). It is very important to have the plastic tray behind the air dam, underneath the radiator in place. It ensures that the predominance of air travels through the radiator. This tray has small ovoid holes at the rear for excess air flow.

As for the window, my driver's side window was tempermental. I went so far as to replace the regulator and motor and still had issues. Come to find out, it was merely a failing window switch. I would suggest starting with replacing the switch before you start replacing the regulator, motor, or both (trust me, that's more expensive than starting with the switch!)

 

Well the list is getting shorter of things to fix. A new motor on the passenger side window did the trick. Horn is now working. I fabricated a new front spoiler and it looks pretty good. I pulled the t-stats. They were different temp. rated. Replaced them, sealed around the radiator and added water wetter. I can now drive 60 mph without overheating but I haven't found out what it does at 80 mph yet. It's no fun being relegated to the "slow" lane on the freeway.

 

keep up the good work CDV!