Hi. I am trying to understand how the front seats cool. Mine don’t feel very cool and so I pulled back the leather and padding on both front seats. There is a small area in the middle where air comes out but the air is not cool. Just air. The seat cool button is on high. Also, I see that the passenger side has a mat of some sort but not on the drivers side. I would assume it should be same on both.

Any guidance would be appreciated. Thanks. Peter

 

It's just a ventilating fan.
From the manual: "VENTILATED SEATS Some front seats have a cooling function in the backrests and the cushions."
Whilst Jaguar also uses the term "cooling" there, "ventilated" is the more accurate. They also refer to "The cooling fan".

As far as I can tell, it's only fair to distribute farts around evenly.

 

Thanks Chris. Any idea what the pad is for as in the pictures?

 

You are brave pulling the seat covers off. I don't know. If it really had cooling there would be refrigerant pipes all the way from engine to seats. They look like copper pipes in your pic, but I think it's just seat support.

If it's only on the passenger side, would it be an ejector seat?

(Based on the white wing-nut in each photo, I'd say someone forgot to put the pad back)

 

Fine line between brave and stupid!
Eject-her seat?

thanks for your help.

peter

 

Hey Chris. I think I figured it out. The pad showing on the first picture is on the passenger side. I believe it is a seat occupancy sensor for the airbag and that's why it't not on the drivers seat.

Peter

 

Hi Peterinio,
I can't see your car model and year. The x358 (post 2007) cars did have heated and cooled front seats with Peltier units. Do you have both the red led button and the blue led button beside it? Chris Mills may have the heated/cooled seats in his car.
The mat under the passenger seat is for the weight sensing function in the airbag (SRS) system. It uses the weight in the seat to modulate the airbag in some way.
The sticky posts have the site where the training courses can be downloaded, lots of information in there about body electrical systems, both pre and post 2007.

 

So they are ejector seats, of sorts :-)

Apologies to my neighbours, but the reason I just leapt out of my X358 and pointed a temperature gun at the seats was because someone yelled "PELTIER".

On max cool, I could find no temperature below ambient (16C, 61F) after 10 minutes, either on the seats or the backs, but I could hear the fans working.
OTOH, on heat the seats were significantly warm in 4 minutes.

I'd sure like to know if some have peltiers, but I couldn't find any reference as of yet.
(I have the cooling buttons with blue leds when on cool)

 

Hi Chris,
Perhaps there is a problem with your coolers, as I can notice the cooling effect on a hot day coming through the seat as I am driving. Whether it's detectable with a thermometer, I'm not sure, but it should be noticeable when driving on a hot day. We may have to wait a while before one comes along!
Pete

 

Well, a fan blowing ambient air will cool. After all it worked at Windscale, at least for a while.

I'd like to know if mine are "faulty" (they certainly don't refrigerate), although it's only a point of interest coz I never use it anyway.

The one time I (proudly) secretly tested the seat heaters on my wife, she yelped and squealed, but not in a good sort of way. What would happen if I tried the "seat coolers"...oh never mind.

(A term TED -Thermo Electric Device- may be used in some Jaguar seat wiring diagrams. I just got lost as to which wiring diagram for which Jaguar I was looking at)

 

If you look in the training book 688-JAG on Jagweb as mentioned in the sticky posts, the X358 Body Electrical Systems on page 9-14, the system is explained. On the first drive in my car, my wife was mighty impressed by the heated seats, and I think it helped me to get her approval. Of course, down here in the cold South, we appreciate our comfort. In Sub-tropical Auckland, you barely need a heater.

 

Thanks very much for the reference, found at
http://www.jagrepair.com/images/Trai...-JAG_10-08.pdf

Very interesting.
"It is important to understand the operation and limitations of the Peltier cell. A Peltier cell has an efficiency of only 5 – 10%, compared to a conventional air conditioning system with an efficiency of 40%. The cell is capable of cooling the incoming air by approximately 8°C (12.4°F)"

"If the temperature in the vehicle is the same as or exceeds the heat rejection side of the cell, poor cooling will be the result."

Anyway, both my seat's cooling is apparently duff, for reasons which might include environmental conditions. Whatever the reason, actual temp drop was unmeasurable with an IR gun (heating was). My VIN indicates 09 model year. My tests are what they are.

Cheers

 

Hi Pete. It's Pete.

09 VDP naturally aspirated.

 

The only problem with the Jag heated seats is that even on the low position they get too hot. I would prefer a rheostat knob.
Also, it is a shame Jag didn't see the value in having an independent control for the heated steering wheel. I believe comes on only when the heated seats are engaged.

 

FYI, I just had a social meeting with the long-time co-owner of the Jaguar Agents here in NZ. (Mark Shorter for those interested). Amazing things happen sometimes.
Mark is (was until recently) the "technical" side of the Shorter (later Archibald and Shorter) official agents in NZ.

So, what would you talk about to a Mark Shorter to pass the time?
I innocently asked if the seat cooling option really was "cooling". He emphatically said "Yes! And It Works!". He even went on to describe large blokes with sweaty bums, but I digress. I didn't ask any further technical questions.

The X358 (at least) is confirmed to have seat cooling (ie refrigeration within the seat, if fitted). both by (obscure) documentation above and by the agent here.

My seat coolers don't work. Either faulty (as measured by a temperature gun at 16C ambient), or possibly don't work until ambient exceeds a certain temp (the technical description is complex). I'll test again when we get into summer of perhaps 25C, since I don't have an oven large enough to put my car in.

If the seat-coolers "don't work" but heating does, that seems a strange fault since the same "peltier" unit is used for both heating and cooling, just depending on direction or polarity?
-----------
The advantage of these cars, is that everyone is so worried about the air suspension leaking, that they probably forgot about the refrigerators in the seats :-)

 

Well then! Apparently my sweaty bum isn’t reason enough to assume that the seats aren’t cooling. I guess I shouldn’t complain knowing my bum would be thoroughly sweaty instead of just mostly sweaty. : (

My wife drives a 2013 Lincoln MKX and the cooled seats keep my bum thoroughly un-sweated! : )

Peter