Dear Jag Enthusiasts,

I have been repairing the driver seat cushion heater, which was inoperative since the black wire disconnected from the cushion heater harness yellow female multi-plug connector. I soldered it back in (see attached picture) and got it working for a while. However, lately the seat cushion does not warm up much and I have the impression that it may be inoperative again.


Yellow female multi-plug connector (center) with red and black wires

I checked the female connector and the wires and found that connector feels loose and both the wires and the connector heat up when energized. The other seats don't heat much either - perhaps reaching body temperature.

My questions are:
- Is there a replacement for the yellow female multi-plug connector?
- Is it expected that the seat cushions heat only slightly? I have seen posts that describe moderate heating due to the thermostat.

Thanks,

Stefan Posse

 

They make a device that goes in the fuse to show how much draw is going through it?I’m just thinking out loud if a person had that device into the fuse box and you could turn the seats on and off if it would show that it was using it power? On all the cars that I have I seriously cannot tell when the seats are heated or not no more than just body temperature warm.

 

You need to remove the electrical terminal from the connector and make a proper repair. THEN insert the terminal back into the yellow connector.

There are tools for removing the terminals, It is easy once you have the tool and the technique.

DORMAN makes after-market seat heater elements. You could use them if your originals are OPEN CIRCUIT. (failed)

 

Hello,

I had a similar problem on my 2000 VDP. The red wire was broken at the connector as well. Was going to get out the pin tools and fix it but decided to just cut off the connector and crimp on a butt splice since I'll probably never be changing the seat heater pads...

 

Thanks for your suggestion. I measured the resistance of the seat heater and it looks like the heater pad circuit is open.

 

Hello,
I also had a similar problem with my previous 2000 Jaguar. The seat did not heat and it turned out the heater element for the back of the seat was open. I ended up bypassing it so the seat heater would work. With a VDP remove the rear tray tables from the seat back and remove the two screws that hold the seat back onto the seat frame, you will see a grey two-wire connector that connects to the seat back heater element. (there are two clips that hold the seat back on the left & right near the bottom; you will need to pry them off and press back in upon reinstalling) You can disconnect it and and connect the source wires together. If that works at least your bum will be warm! If it's not a VDP, seems you will need to pull up the rear seat cover to find the connector. A bit of doing but it's in there somewhere.

Squab heater element bypass

 

If your seat thermostat is ng it will only get warm change it with a 15 amp fuse. Just pull seat cover forward to change it no need to remove seat. You will need to turn heater off after a few minutes as it gets hotter quickly

 

Thanks much much your suggestion. I have an XJR. Pulling the rear seat over seems more involved. I'll take a look.

 

I assume that the thermostat can be replaced? Where is a good description to access the thermostat in an XJR?

 

I have a spare thermostat. If you find yours is open, let me know and I'll send it to you....

 

Dear All,
We found that the seat heater pads have an open circuit. The thermostat is good.
Can you suggest a trusted supplier for the seat heater pads?
Thanks,
Stefan Posse

 

Hello,
I finally got back to diagnosing the failed driver seat heater. The resistance of the Driver Seat Cushion Heater circuit is 0.3 Ohms. Does this make sense or do I need to need to track down a short? The Driver Squab Heater circuit resistance (I am assuming that this is the seat back) is 1.4 Ohms.
The next step will be to order a replacement Multi-lock 070 3 pin Female Connector, which is broken.
Thanks,
Stefan Posse

 

The seat heater works again after repairing the connector.

 

Looking over this thread, it appears there are many points that can fail.
We are fortunate to have some experience reflected in this forum that
can help us sort it out..