Retrofit heated rear seats, pre-LCI e83

davebrossi · 09-08-2023, 09:51 AM

Hi All,

long time lurker, probably because many things I'm able to chase down are provided at a level I can comprehend (comprehension level; ...dunce?) courtesy of Bentley's. I have enjoyed keeping my beat to death 2005 e83 going, and VERY slowly bringing it back to life.

Something I decided I wanted to take a crack at last summer was the idea of adding the optional rear heated seats option found in the LCI e83. I acquired OEM seating with heating elements, I acquired the necessary switches, and in looking at the wiring harness diagrams in Bentleys I -thought- I was on my way...

Despite several attempts, and successfully bringing power to the two switches, that's where the story ends. My understanding is that while those with LCI updated cars have the harnesses hidden under the carpet, it took BMW a few years to realize this was a good idea.

I'm hoping someone might have completed this project successfully previously and might have some ideas. Again, LCI have things ready and hidden, but I'm about to pull the entire cabin's carpet, and suspect nothing is hidden waiting for me. I am happy to describe more (including resurrecting the photos of the diagrams given by Bentleys, the interpretations I had on how to provide power to the seats, how the switches should be wired in, etc). Before I start a wall-o-text, just testing the water since...

is usually what I end up doing.

2005 e83 M54, 188k miles.

Conv_George · 11-11-2023, 04:02 PM

I put some front seats from a e53 X5 which were heated into my 05 X3, which wasn't originally equipped with heated front seats, and discovered the wiring for heated front seats was missing entirely - no power wires to the switches (I got the correct switch panel for my X3 with heated seat controls,) and no wiring from the switches to the seat. So last month I scored the connectors for the switch panel and the seats, just need to run some wiring.

So, my guess is the wiring from the switches to the seats isn't present in your X3.

I can tell you that when I put heated M6 vert seats into my 01 330ci vert when I plugged them in the heat worked immediately, but the previous seats were heated as well.

I have also managed to put the massaging seats in my former e38, just some simple wiring for that.

09-08-2023, 09:51 AM	#1
davebrossi Registered 0 Rep 2 Posts Drives: 2005 BMW X3 3.0i Join Date: Aug 2021 Location: Ammon, Idaho iTrader: (0)	Retrofit heated rear seats, pre-LCI e83 Hi All, long time lurker, probably because many things I'm able to chase down are provided at a level I can comprehend (comprehension level; ...dunce?) courtesy of Bentley's. I have enjoyed keeping my beat to death 2005 e83 going, and VERY slowly bringing it back to life. Something I decided I wanted to take a crack at last summer was the idea of adding the optional rear heated seats option found in the LCI e83. I acquired OEM seating with heating elements, I acquired the necessary switches, and in looking at the wiring harness diagrams in Bentleys I -thought- I was on my way... Despite several attempts, and successfully bringing power to the two switches, that's where the story ends. My understanding is that while those with LCI updated cars have the harnesses hidden under the carpet, it took BMW a few years to realize this was a good idea. I'm hoping someone might have completed this project successfully previously and might have some ideas. Again, LCI have things ready and hidden, but I'm about to pull the entire cabin's carpet, and suspect nothing is hidden waiting for me. I am happy to describe more (including resurrecting the photos of the diagrams given by Bentleys, the interpretations I had on how to provide power to the seats, how the switches should be wired in, etc). Before I start a wall-o-text, just testing the water since... is usually what I end up doing. 2005 e83 M54, 188k miles.
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11-11-2023, 04:02 PM	#2
Conv_George Registered 0 Rep 4 Posts Drives: 01 330Ci Vert, 05 X3 3.0 Join Date: Sep 2022 Location: Washington, NC iTrader: (0)	I put some front seats from a e53 X5 which were heated into my 05 X3, which wasn't originally equipped with heated front seats, and discovered the wiring for heated front seats was missing entirely - no power wires to the switches (I got the correct switch panel for my X3 with heated seat controls,) and no wiring from the switches to the seat. So last month I scored the connectors for the switch panel and the seats, just need to run some wiring. So, my guess is the wiring from the switches to the seats isn't present in your X3. I can tell you that when I put heated M6 vert seats into my 01 330ci vert when I plugged them in the heat worked immediately, but the previous seats were heated as well. I have also managed to put the massaging seats in my former e38, just some simple wiring for that.
	Appreciate 0 Quote