Heater/Air con blower motor runs,but very poor air flow into car.
Bob,
What year and model is your Jaguar?
Paul
As Paul says, Bob; year and modelā¦
But also do you have two speeds working with manual setting?
Frank
xj6 85 Sov Europe (UK/NZ)
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Hello Frank, my car is a 1992.
And all 3 fan speeds work.
Regards Bob
Hello Paul my car is a1992
Regards Bob
Bob,
Welcome to Jag-Lovers! I see from you profile that you are new here.
I also asked what model your 1992 is. If it is an āXJ6ā then you are on the wrong list and should be on the XJ40 list as Jaguar completely redesigned the XJ6 and introduced it in the USA in 1988 (other times in other countries). There are very few parts in common between the cars discussed on this list and the XJ40s.
If you have one of the last Series III XJ12s (5.3L V12 and two fuel tanks) then this is the correct list for your car.
Paul
It is a double six and as this goes he has the Delanair Mk III with the electric actuators. The XJS list might have more information, even though this is the proper XJ list - Donāt know about the XJ40.
Iād recommend searching the archives. Maybe one of the fans is down or some of the flaps do not actuate properly,ā¦
Hello all ,my car is an XJ12 series three.
Thanks Bob
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As David says, Bob - you probably have the Delanair with
more advanced controls.
The logic of the Delanairs is likely the same the same; temp control by heater core bypass. However, if the fans, which are electronically controlled, can run at full speed without appreciable air output to the cabin - air ducts may be detached or clogged?
As said; consulting the xj40 list is advisable - even if the fault may be relevant for āourā versionsā¦
Frank
xj6 85 Sov Europe (UK/NZ)
**
Bob,
Thank you for identifying your car as a 1992 Series III XJ12. This is the correct list for this unusual car. Your car is different in many ways from the cars usually discussed on this list as the last years of the Series III saloons included the Delanair MK III climate control system (used in the XJ40s and later XJ-S/XJS), Anti-Locking Brake System (ABS), the battery was relocated from the engine bay to the trunk to make way for ABS, and a CD changer in the trunk. I recommend that you always identify your car as a 1992 Series III XJ12 when you post since it is different from the cars usually discussed on this list. Some people are not aware that Series III production did not end with the XJ6 in 1988, but that it soldiered on until 1992 with the XJ12s and Damiler Double Six (DD6) and evolved along the way. I have a slightly earlier Canadian Market 1990 V12 Vanden Plas (essentially a DD6 six trimmed for the Canadian market) with the Delanair MK III but doesnāt have ABS so its battery is still in the engine bay. All of the Series III XJ6s had the Delanair MK II and their climate control system is different in many ways from your Delanair MK III.
I suspect that David Jauch is correct that one of your heater blower motors is inoperative. There are two of them, one inside each side of the front dash, and when one fails the blower motor output is dramatically cut down because of how the airflow is managed. One way to determine if this is true is to first inspect each of the two 50A blower motor fuses (one located in each of the main and auxiliary fuse boxes beneath the dash) to verify that they are both still good. Then remove one heater blower motor fuse at a time and turn on the fans with the Mode Selector Switch to the High to verify that they both work individually and again together with both 50A fuses installed.
I had the reduced air flow in my 1990 V12 Vanden Plas a few years ago and at first I didnāt suspect a blower motor because I could hear the blower motor sound in the car. What I didnāt realize at first was what I was hearing was only the sound of one blower motor and not two. Luckily for me I was able to return the inoperative blower motor to normal operation simply by removing, cleaning, testing and reseating the fuses.
I hope that your fix is as easy. There are of course other possibilities, but this is the most likely cause (and least expensive) and should be investigated first.
Paul
Hello Paul thank you so much for your input, I will check my fan motors fuses tomorrow, but think it may be a flap problem.
Many thanks Bob
Bob,
Please write back with your findings and what resolves the blower motor issue in your Series III 1992 XJ12. This will help the body of Delanair MK III knowledge on this list since most members have cars with the earlier Delanair MK II system. I have two Jaguars with the Delanair MK III system and I am interested in more knowledge about keeping them working properly.
Paul
Hello Paul, proberley will not get round to getting behind the dash for a while as I am busy putting the rear end together on my 1910 Cadillac roadster at the moment, will check the fuses though this weekend and will keep you posted.
Regards Bob
Bob,
Great. The idea is to not only check that the fuses are good, but to remove one fuse at a time to electrically isolate one fan motor at a time to make sure they both work independently when the heater blower motors are turned on. I was surprised to discover that I had only one operative heater blower motor in my 1990 V12 Vanden Plas because it sounded like they were both working.
Paul
This is a good and easy test. I have a 1987 SIII V12 and discovered the passenger side blower was not working at all by removing each fuse one at a time. I wasnāt lucky enough to fix it with a new fuse or by cleaning the fuse unfortunately, so pulling the blower on that side is on my to-do list after some higher priority maintenance. Iām hoping a replacement darlington transistor will do the trick.
1 Like
My next problem is low oil pressure at idle, have replaced the sender with an O/E unit,but that did not fix it.
I ran a wet test and the oil pressure is 80 psi.
Any suggestions ?
Bob
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What is the actual oil pressure, Bob - and at what rpms? What viscosity oil - and does the warning light come on? How long since filter replacement?
The usual procedure is to attach an external gauge - to positively eliminate a gauge and sender faultā¦
That said; the engineās requirement for pressure in idle is very lowā¦
Frank
xj6 85 Sov Europe (UK/NZ)
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V12s commonly have very low pressure at idle, with the needle almost nudging the ā0ā. I wouldnāt be alarmed.
The switch for the oil pressure warning light is calibrated for about 4 psi as I recall. As long as your light isnāt coming on at idle you should e OK
Cheers
DD
Bob,
for the sake of others to come it would be helpful to make a new topic if you switch from heater blower to oil pressure. Rest assured that you will receive just as much help under a new thread.
As for your question Iām sort of confused: oil pressure is measured twice by the Jaguar stock setup (and I suppose for V12 just as for XK) - once for the control light and once for the OP guage. Rigging up an independent device is quite an endeavour.
Your statement about the wet test rather hints at compression than at oil pressure plus 80 psi would rather trigger the relief valve if relating to oil pressure ā¦
So are you talking about oil pressure or compression?
Good luck
Jochen
75 XJ6L 4.2 auto (UK spec)