Climate control ODB codes B1263 and B1265

[commsinfo351]

Hi all, we have a 2004 S type 4.2 SE that all of a sudden only blow hot air out of all vents! My question, is there a heat blend motor that shuts out either hot or cold air? We used to hear a clicking/slight knocking noise from just below steering wheel by my left knee area?
All the vent controls to send air to screen, vents and footwell all operate correctly!
Moving the temp controllers do nothing when moved to cold or hot all we get is very hot air from the vent that is selected?
I have seen lots of posts about the ccv and associated module failure but would this cause my problem where it failed instantly with no burning smells etc?
Also my local Jaguar specialist said the module almost always blow when the ccv fails is this common? Suggestions welcome. Thanks

[ptjs1]

commsinfo351,

There seem to be a couple of possible causes:

- The obvious one seems to be a stuck heater valve, which isn't too difficult to replace.
- The other more obscure cause is there are reports of the loom getting water-damaged under the front bumper which can cause this symptom.

Good luck

Paul