There is an easy way and a less easy way to retrofit heatet seats to your 451. It really
depends on the year your smart was made. From around 2008 onwards, smart started
to include all the wiring for the heated seats so all you have to do is plug in a few things.
How Do I Know If I Have The Wiring?
Simple, have a look at the following info and check under the seats for the heated
seat wires (white connection) and look under the dashboard for the relay base.
I Have The Wiring So Please Continue
Here are the non heated Pulse seats, they are nice, half fake leather
and material but they aren't as nice as the Brabus leather seats I have.
Look under the seats and disconnect the connections. The white one is the heated
seat connector which is plugged into a holder to stop it flapping about. The blue connector
is the seat belt reminder circuit and the remaining connector will be yellow, red or pink
(not shown below), this is the side airbag if you have them. When you have the side
airbag disconnected, do not turn your ignition on unless you like error lights.
Remove the existing seats and replace them with the new seats. You won't have
Dr. Theopolis from Buck Rogers under your seat nor will you have a 13 on your keys.
Bolt the new seats in place and plug in all of the connections underneath.
Look under the dash as shown below, just above the brake pedal you should see a relay base.
On LHD cars the relay base is found on the left, under the dash, just in front of the SAM unit.
Whoomp there it is (Tag Team, 1993)
And this is the relay you require, the part number that you need to take into smart is
written on top as shown in the picture but for you of limited intelligence, A451 820 0085
and you can buy it from a smart dealer. No, you can't buy them new anywhere else for less.
The relay pushes into the holder with the writing facing UP.
Your button bank will look something like this (no heated seat buttons at each end).
You need to get a new switch bank with the heated seat buttons. It's not
something you can add to your existing switch bank unfortunately as not only
are the LEDs missing but all of the SMD resistors and transistors too.
All of the other switches that may be missing on the new one (like the front fog light
switch in my one) can be swapped over from your old button bank to the new one.
With that plugged in, start the car and press the buttons. The 1st press brings up
2 lights which is full power. The 2nd press leaves you with 1 light which is half
power. Pressing again turns all the lights and the seat heaters off.
And that's you done, just in time for Winter. Toasty!
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