My '04 XJ8 blows cold (a/c) air from the driver side vent but not heat. Maybe a blend door controller? Where is it and what's it look like?
Thanks

 

I believe silting up of the heater radiator core is sometimes a cause. Back flushihng sometimes cures it but of not, it needs a new rad in the heater box. AFAIK it is not outrageously expensive to replace.

 

Thanks. Seem to get plenty of hot water thru the heater core and all other vents work great. I will get some heat if its on long enough and set high enough.
What's a "rad in the heater box"?

 

The driver and passenger side systems are separate from an air-flow point of view but have a common heater core that spans both sides of the system. As Fraser said, one side of the core often gets silted up so if back flushing doesn't fix it a new core will be required.

I had the core on my '04 changed a year or two ago because of this issue.

 

It's the heater core, (or radiator). I use the word radiator because it carries out the same function as the engine radiator, transferring heat from coolant to the air.

 

Back flushed entire system with special attention to heater core. No problems noted, everything pretty clean. Any other ideas? Seem to be two control modules behind driver side dash but I don't know what they do
Thanks

 

I have a 2005 XJ8 and mine has the same symptoms. The dealer says the problem is the blending door (mechanical). The servo motor is not working, and the only way to fix is an entire new heater box $3,000 installed. There has got to be a less expensive alternative?
Anyone have any suggestions?

 

No luck so far. Don't know where the vent door is, don't know what it looks like, don't know if its mechanical or a controller. No luck finding any pics or instructions. If its mechanical can it be wired open? Someone also said it may be the DCCV. Same problems as the vent door. Let me know if you have any luck (aacbsfb@gmail.com)
Maybe its this site. Same issues with wanting to recover the B Pillar!

 

I think I read that it is the same heater box as in the Lincoln Cont. perhaps the Lincoln part could be installed and work in the Jag? That may save some $$

 

Acb - mine is doing the same thing. I think if you search the subject you'll find lots of this problem. My Indy mechanic assumed it was blend doors; it was not. I'm going to book a heater core replacement. I think he said total job is around $500.

 

""No luck so far. Don't know where the vent door is, don't know what it looks like, don't know if its mechanical or a controller. No luck finding any pics or instructions. If its mechanical can it be wired open? Someone also said it may be the DCCV. Same problems as the vent door. Let me know if you have any luck (aacbsfb@gmail.com)
Maybe its this site. Same issues with wanting to recover the B Pillar! ""

Hey you guys!
Sorry you are not making progress.
If you both want to email me @ robatmeirion@gmail.com I will send you attachments:

Technical guide
Electrical guide

Some info here https://www.jaguarforums.com/forum/showthread.php?p=284793#post284793
Bob