How do the "cooled" seats work ? I have a late 2015 Autobiography which I purchased 2 years ago as a ex JLR management car when it was new to me the cooled seats provided a real cooling feeling but now you can feel the air flow but its hardly cool. Is the a separate air con unit in each seat or is the feed of air from the cars air con supply , can it be serviced or indeed does it need servicing ?

They run separate from the main aircon . Iirc they run off something called a peltier heater that’s actually in the base of the seat, the L322 did anyway . Once Craig is on a tea break he may come along with his legendary knowledge
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Very similar to the L322, description from Topix:

Quote:

A front seat climate assembly is incorporated within each front seat cushion and the backrest of the seat. The Seat Climate Control Module (SCCM) (Driver and Passenger side) and electrical wiring are located beneath each of the front seats.

The climate modules contains Thermal Electric Device (TED), which heat up or cool down depending on the voltage provided by the SCCM. Each climate module also contains a blower, which blows air over the TED to distribute the heated or cooled air through liners in the related seat cushion or seat backrest. The blower is also controlled by the SCCM.

Mr Tee wrote:

Once Craig is on a tea break he may come along with his legendary knowledge
I

Strictly coffee for me sir Tea's drank by old people!

Tried mine for the first time yesterday, remarkably impressed, I did think they were going to be a bit lame.

Thanks for all the replies , Defo a coffee drinker LOL

If they’re similar to the l322, they’ve got air filters that need to be swapped out regularly

never heard of these filters for the cooled seats. the book doesn't mention them. Any idea where they are so they can be checked?

The filters were dropped for the L405

I looked up the part and the filter is still on there... Whether they give you access to it or not is another story but the peltier sort of needs an air filter.

Fifth Horseman wrote:

The filters were dropped for the L405

Where are the filters situated and are they meant to changed or just cleaned as I can't find any reference to them on my "official" service checklist , Thanks

There are two units in each seat, one in the seat back and one in the cushion. Yes the filters need to be changed out and this could very well be your issue. If your seat heating still works then the system likely isn't broken. The heating action relies on all aspects of the system working as it should, cooling the system can be damaged/faulted and still function. The peltier cell is the thing that provides the heating and cooling. When on one side of the peltier cell heats, the other side cools. When heating it moves air around closed loop in once direction through the system on one side of the cell to warm. When cool it is open loop drawing air over the cold side of the cell in another direction and out the perforated area of the seats. If the filters are clogged it won't be moving very much air over the cell which results in diminished cooling. When cooling it should be roughly 8 degrees F below the ambient.

I have not looked at my l405 yet, but on my l322 the filters were on the front outside edge of the seats on the bottom. It is a round fabric filled thing, clearly looks like a filter. You turn it and it pops off. You can get replacements on amazon/ebay for a couple bucks each. The seatback unit however is much more difficult to reach. The seat back has to be removed in order to access it though IMO since it's located within the seat itself, this filter rarely clogs with particulate. In my experience the filter material even though possibly not clogged up with particulate becomes ridged over time and inhibits air flow so it is a good idea to replace them.

The other issue is the unit itself over time is prone to physically cracking, depending on where it fails you may loose the heating/cooling function... tho as previously stated, if your heating still works well most likely the system is okay.

Also possibly helpful to mention, if you have a capable diagnostic you can actually monitor how the cells are performing, there are several temp sensors throughout the system... If you live stream the temp sensors on the particular seat WITHOUT it running. All the temp sensors should read roughly ambient. If there is one temp sensor displaying some improbable temp the whole blower unit/peltier needs to be replaced. That or maybe the seat itself throws a code and disables itself (but not always) with no diagnostic if the heating works, you're likely in good shape. When heating the system makes use of all its temp sensors in an attempt to not set fire to the car

Brad S1 : Thanks for all that , Getting the Autel out tomorrow when I get home .