hi guys, my names sam, im new to the forum! got a question and probably a few solutions too if any of you are also having this issue, it seems to be extremely common! if you have any questions on it please ask.

i know im the one asking the question but with this job, ive found alot of info on the matter! this one seems to be the same fault as others, but a different source, and as ive checked evey little thing it could be theres a high chance ill be able to help


i have a issue with heating on a jaguar X308 (xj8) i see its very common, and ive read many solutions on your site, but still no luck. it wont blow heat at all. a list of the things ive done:

changed the coolant valve
checked the pump - working
ran diagnostic test (OBD) - will blow hot during diagnostic actuator test!
checked matrix, flushed matrix.
gained fault codes, only 23 beeps and is active ( A/C pressure) then suddenly they will all start beeping! 23,34, 41, 42, 46.and i have found what they all are, but as its virtually impossible for all of them to fail im looking a to a more direct source!

checked ext temp sensor ( which is reading high! up to 35c when here its between 8-16c) but not faulty, done a temperatuer and resistance test to ensure this.

checked in car aspirator and int temp sensor - working
checked coolant temp sensor - working
the thing is, if the valve, pump, or matrix was faulty, it wouldnt blow hot during the diagnostic test! but it does, its like the system is fine, but its receiving false signals from another source( eg. the control module, or a/c computer itself) to close the coolant valve when it shouldnt be. like its telling its self its too hot therefore the accm shuts the valve dissalowing any hot coolant to the matrix!

i only have a few more suggestions, and after days its getting on a bit now. next things to do, check the blend door operation, and the heater matrix temp sensor as that is what controls the water valve. its the last thing i can think of that would cause it other than the accm computer. if you have any suggestions, or anything to back what ive said, that would be fantastic! many thanks guys!

 

Welcome to the forum Sam,

That looks like a UK Post Code in your 'location'? This is an international forum and 'Town, Country' will help everyone.

You could have a lot worse issues with an X308 than no heat but the way the temperatures are falling in the UK over this last week, that may not be much consolation!

Follow this link XJ ( X308 ) XJ8 / XJR - Jaguar Forums - Jaguar Enthusiasts Forum to the X308 section for help, advice and information.

Remember to add vehicle details to your Signature to help others to give relevant advice. Go to the User ID button on the left of the top menu bar, then Settings & Options under Your Control Panel. Select Edit Signature and enter the details.

You can also visit the UK Region section by following this link UK - Jaguar Forums - Jaguar Enthusiasts Forum to find other members in this country.

Hope you get the heat on soon.

Enjoy the forum.

Graham

 

Welcome to the forum Sam,

Good to have you with us.
Follow Grahams advice above.
Enjoy the forum.

If you haven't already done so you should add your car details to your signature to help others to help you.

 

Hi & welcome aboard Sam, Its good to have you here with us here at Jaguarforums.

hope we can help out some...in the meantime please check into the relevant section for your car for the best responses

Any useful site information you may need such as how to post pictures, edit signatures, add videos, use the search facility etc, can be found here
within the following link Helpful_information


Please also take the time to check out the regional section for your area!
There are lots of members local to you with the same interests with info on local dealers and possible meets.
Regional - Jaguar Forums - Jaguar Enthusiasts Forum

I've manually upgraded you to full forum access so you can better view the whole site and all its features.

Please Jump on in and enjoy the site.................

 

ok guys,vehicle details and address all sorted thanks for the directions! I am indeed in england , and your right, is bloody freezing!! havent got the car at the moment but ill be back trying to sort the problem at the weekend. in the meantime if anyone has any information please let me know. thanks guys!

 

Sam,

Thanks for adding the details.

Here's a few ideas for the lack of heat:

1. coolant flow valve stuck
2. motorised in-car aspirator seized
3. cool air bypass damper stuck open
4. blocked air inlet
5. low blower motor speed
6. low coolant
7. thermostat stuck open
8. heater pump seized
9. air lock

Favourites are (1) and (8). Go to X308 section for advice if you need information on location and checking.

Graham

 

I have renewed the valve, checked the pump - both working
in car aspirator - working
coolant level - fine
blower motor speed is good
thermostat- tested, working to manufacturers spec.

All things that were originally suggested a few weeks ago by people, have been checked, and also a lot of things it could have been that i know from experience.
when i do the in car diagnostic test, and actuator test, it blows hot like theres no tomorrow, so there cant be anything in the mechanical system thats faulty. its capable of blowing hot air, its just being told not to by something, something electrical is sending a signal to the valve to say it should be energized and shut, and also that the outside temperature is well above what it is here. it reads up to 35c, when its actually more like 8.5-10c. so somewhere along the line thats linked. the temp sensor thinks its hot, so it energises (shuts) the coolant valve allowing no hot air to the matrix. im just trying to figure out whats causing that and why. ALSO if i UNPLUG the coolant valve so its not energised, (open) it blows hot! the valve has been renewed, so its not the valve, but whatever it is that electronically controls the valve is sending incorrect signals, either the heater matrix temp sensor or the climate control computer, or control module. of course it could also be, any of the other things stated that could cause it, like the blend doors or motors being faulty and causing one of the parts to read an error and shut the valve. i really dont know :/ totally ran out of ideas, it seems like a very rare way for this to go, as one of you said, the favourites to go wrong are the coolant valve or the motor. but both are working. any ideas!? many thanks for the quick replies by the way!

 

Stick with it Sam...

In the meantime, this is the new members thread and you simply won't get the responses you need in this section.

Please start a new post in the relevant section for your car

You can of course simply copy /paste the bulk of what you've already written here as a quick way of doing this.

Good luck