I started and ran it for about 8 minutes. I get no heat through the vents. I checked for cold air from air conditioner and got plenty. Also there is a slight fogging up of the windshield when I have it set to heat. Anyone have an answer or can give me the possible problems to correct?

 

• Clogged heater core
• Poorly functioning/broken auxiliary coolant pump
• Malfunctioning heater control valve (or whatever it's called, it switches on/off flow through the heater core)
• Faults in wiring to either of those systems
• Faults in climate control modules
• Crimped/blocked bypass hoses

listed roughly in order of likelihood. Much useful info here, including how to check the climate control module for codes. Be sure to clear any old codes before checking them again, mine had 5 but once I cleared them no codes showed up: https://www.jaguarforums.com/forum/x...nfo-faq-66454/

You can try backflushing the heater core, seems to be a pretty common issue with pretty reliable success of fixing. You can also put hands on the heater pump (located against the outside of the driver's side false firewall) and see if you can feel it vibrating (while the heat is on and set to max temp ofcourse).

 

few things it could be. Does it give any heat under load? (3000+ RPM?)

 

You might want to try this. After the engine is warmed up press the temperature red arrow until its reads HI. If you get heat then the problem is most likely the ambient temperature sensor.
I had great automatic air conditioning but could only get heat set on HI.

 

My issue was the aux pump, which was a ten minute job to replace (mine was beyond brush repair, but that could be possible if yours isn't - they get worn out. There's a DIY somewhere floating around for that). My symptoms, were no heat unless under load, that's why I was asking before. And even that heat wasn't LOTS of heat, just enough of it.

 

Put the temp to high and make sure the A/C button is not lit. press the face button. You should have plenty heat.

 

It's generally a frozen aux pump, this is located under the coolant header tank, a bit of a git to get to. Give it a clonk / take it apart and grease if it doesn't buzz when the climate is set to heater.

 

Where is the header tank located?

 

How do I get to the frozen aux pump, that is located under the coolant header tank?

 

https://www.jaguarforums.com/forum/x...nt-diy-172933/

 

My first thought would be to flush the heater core, as Nil said, it is the most likely culprit. But I've learned over the years to just default to whatever Sean suggests, so definitely check that aux tank as well.