All,

After a good bit of searching through the FAQs and posts, and even finding an entire website devoted to climate control issues (- JaguarClimateControl.com - thank you to the authors for that one) I am stumped.

Unlike most of the DCCV-related problems I found, I have the opposite: I always get ice-cold air, from both sides, with the exception of attempting to push the thermostat up beyond about 75F; when I try to do this, the motor appears to cut out, and the air flow stops, but what I do feel above the dashboard is just as cold.

Setting the thermostat (on either side, mind you) lower returns the air flow, at the same ice-cold full-blast temperature and fan settings as before - there is no alteration in the temperature, only the fan flow.

Before I start swimming with sharks, I should note that I have attempted to bleed the thing before, and in doing so, noticed that the lower hose is significantly vacuum-compressed, and relieves itself somewhat when I open the filler cap, but massaging or otherwise manipulating this hose doesn't do much for returning it to an otherwise functional diameter.

My assumptions thus far are that either I have enough air in the system somehow to completely occlude the heater core from filling (unlikely considering the normal running temperature, even at extended idle, and the concomittant issue of the fan speed change), the DCCV has failed in the closed position (always-ground), or the climate control unit in my dashboard has suffered a hitherto-as-yet-undetermined failure - or the grand-daddy of them all, a mixture of the above in a delicious pre-winter melange of failure.

I shouldn't complain, I suppose - as it's already halfway through December and Houston has been blessed with decent weather thus far, but I fear in the coming weeks I may be frozen, should I not address this soon.

Ideas, comments? I am going to attempt to get some better diagnostic data (voltages, etc) today, and post my results in an attempt to ferret this issue out.

Cheers, and happy motoring !

 

Open the coolant bleeder caps. She's full of air.

 

Could be air, but DCCV can fail stuck closed (or any other position).

 

Thanks to both of you for the suggestions - I assume there is more than one bleeder cap than just the one on the expansion tank?

I have looked through JTIS, and it's great for MY up to 2004, but something tells me that maybe its not valid for 2005 ? I'll keep digging, and thank you again to everyone on this forum - you guys are amazing.

 

No there's only the one on the tank with the later cars.
Mine bleeds fairly easily but I usually have to drive a bit and top up again.
When you say ice cold, do you mean ac cold or just ambient?
Do the pipes to the heater core feel hot, in and out?

 

Be sure to try the HI setting, too.

 

Youre in houston, home of eternal ac on. The valve is stuck closed and or so is the heater core. Orrrrr, you have a mouse that made a nest in the hvac box by eating through the cabin filter and plugged the heater core so you dont get airflow

 

Brutal Thank you for chiming in; I tried the bleeding, and it issued a short hiss, then liquid, even as the car was running and up to temp.

Perhaps I did this wrong. Feeling around the hoses, both outlet from the DCCV seemed to be palpably warm, but not to the extent of the others - so I suppose now I get to remove the DCCV and check other ways.

This brings me to my next question (related, however): Is there an aftermarket (by aftermarket, I mean, some place in Houston) source for the hoses, and a list of what hoses I need ?

The ones on my S-type look badly in need of replacement. The previous owner of this car had been hospitalized for about a year prior to my purchasing the car, and was therefore unable to drive it, and it sat in her condo parking lot for about as long - this is just one stop on a list of many things that I'm working on to remedy. Ideas?

I can order the hoses from RockAuto, but it would help if I knew what hoses I needed to order to do a complete hose refit... While I'm down there I might as well replace all the hoses and not worry about them.

 

Grab JEPC from here.

 

Ermahgerd Once again, to the rescue. JagV8, you, along with joycesjag, Brutal, and the other stars of this forum most certainly reside in the upper eschelon of the ranks of the esteemed

I cannot be more grateful, and I am eternally in your debt.