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Hi everyone, I am having trouble with my 2005 S Type R. I have read some of the other threads about this common problem but I’m not sure what to consider next.
This summer I started having trouble switching from heat to AC. It took a few attempts pushing buttons to get what I wanted but it would eventually change. After a month or two of that, I could no longer get any heat no matter what I did. At that point the DCCV valve was changed, the auxiliary water pump was changed and the climate control panel was repaired. Now I only have varying degrees of heat, never cold air! The drivers side runs hotter. Through the setting range of “low” to 62 up to 88 to “high”, I’d estimate the temperatures I feel are:
Drivers side: 82-88 degrees
Passengers side: 68-75 degrees
It doesn’t matter if the AC is on or off.
It doesn’t matter if the the “recirculation” button is on or not.
What do I consider now? The AC seems to be working. I can hear it click off and on, the line gets cold when it’s turned on. Apparently there is a code B1265 but I have read that is perhaps a red herring since the bypass actuator was removed starting with VIN# N10330? My VIN# is N36177. Any suggestions?
Please do, and then be sure to report in this thread what you find.
From your initial description, it seems the symptoms changed after replacing the DCCV. That part has a very high failure rate, so please don't rule out the possibility the new DCCV has failed. Details of how to test it are in the troubleshooting guide.
If the new DCCV has indeed failed, don't go back to the same vendor for another one. You'd stand a good chance of getting another bad one if from the same detective batch. This applies to any parts. I do not care to discuss how I learned this.
One little bit of advice. You're new here so will be forgiven, but complimenting me is considered a major breach of forum etiquette. The old-timers will attest it makes me even more insufferable than usual.
Outside temperature:
29 (a nice winter day here in Canada).
Passenger side duct temperature: 38
Drivers side duct temperature: 178
I’ll try test 2 tomorrow morning when everything is cold again. Looks like I’ll be doing a Hail Mary on the electrical, then probably buying ANOTHER dccv.
I guess it’s time to confirm the electrical is ok. Any advice or input?
Sorry for the late reply. Been working on a cryogenic freeze chamber for married men to get through the holiday season. Still working out the bugs. Seems to work okay in concept, but it thawed me out over a week early.
Sure sounds like your DCCV is staying open on the driver's side. A little over half-way down on this page, you will see some electrical checks (resistance and amperage) you can do. This was on my '02 V6, but I think later models will have similar results:
The control module on 2003+ modules are prone to damage by a defective DCCV. Poke around that website for more details about an upgrade to prevent this.
Thanks for the input. Every vehicle has weak links. This is definitely one of Jaguars. I won’t have time to continue this until I return from a trip this week. It’s an 8 hour drive each way so I’m concerned my freshly repaired control module may be damaged by my new, apparently defective DCCV. Should I keep the temperature setting on HI so it at least is sending the appropriate signal for what the DCCV is putting out? Most of the trip will be in 20-35 degree weather so it won’t be much of a hardship.
For background, this is the sequence of events with this issue:
Summer: temperature response to control input seemed to become spotty. I had heat but it usually took a few attempts to get AC.
September: lost all heat.
October: Mechanic told me the auxiliary water pump wasn’t working. I replaced that pump myself. Still no heat.
Late October: I took it back to my mechanic. I was told it needed a new DCCV. He told me the DCCV electrical was good and the AC worked. He replaced DCCV. Still no heat.
Early November: He sent the climate control panel (module?) to be repaired (not Jaguarclimatecontrol). Reinstalled and joyously I had heat! Unfortunately, I only had heat. Couldn’t stop it regardless of temperature setting, at least on the driver’s side. Control panel returned to repair company for assessment.
Late November: Control panel reported to be “properly repaired and functioning” by repair company.
Early December: Control panel returned and installed. Same results as shown by recent DCCV tests 1 & 2. Always heat on drivers side, passenger side can close but doesn’t open completely.
It’s an 8 hour drive each way so I’m concerned my freshly repaired control module may be damaged by my new, apparently defective DCCV. Should I keep the temperature setting on HI so it at least is sending the appropriate signal for what the DCCV is putting out?...
That would not be a bad idea, if you can handle all that heat. When HI is selected, power through the DCCV is switched off and the valve is supposed to spring load open for maximum heat. We still don't know if the DCCV is mechanically jammed (swelled seals, for example) or if the electrical side is kaput. Either way, protecting the control module would be a good idea by selecting HI.
One option to limit heat is to clamp off one of the lines. I'd suggest the driver's side, since that is the one acting up the worst. That way, you'd only get about 50% of the normal heat output and hopefully won't roast yourself out of there. I've used long-nosed Vise grips for troubleshooting, but I'd be a bit hesitant to leave them installed as they might pop off somewhere on your trip. Perhaps an inexpensive clamp like this would be more likely to stay put:
I would be a little hesitant to leave the line clamped shut for several days, as the rubber may take a set. Maybe you could apply the clamp before leaving and then remove it on arrival, to be reinstalled for your trip home.
Good suggestions, I’m a couple hours into the trip at this time, using my passenger window to blend in a little 28 degree air. I’ll stop at the next city to see what kind of clamp I can find.
Heat/AC problem
