Recaro seat wiring; looking for explanation

Hello everyone,

My name is Mike Clifford, and I have a small vintage race shop. I work on European race cars from the 1950s and '60s. Really fun stuff if I do say so myself :)

But that's not why I'm here. My daily driver is a 1987 BMW 325i. I just bought an awesome pair of Recaro seats for it. Both seats have heat, power reclining, and a tiny air compressor for filling lumbar bladders.

I'll be wiring the heat in using a factory harness, so no worries there. I'm a bit confused about the ideal wiring process for the electric recline and the compressor.

Each seat has a red wire and a brown wire which power both these functions. One red and one brown per seat. The buttons to control these functions are located on the seat, and they are lighted. This was my plan for wiring in both seats:

The car has an auxiliary fuse box from the factory with a hot lead and an ignition-switched lead. Since the buttons have lights, I need switched power to avoid draining the battery. My thought is to wire in a relay. The power source pin runs to the fused hot lead, the switched pin runs to the ignition-switched lead, the load pin runs to the red wire on the seat, and the ground pin runs to the brown wire on the seat.

Since there are two seats, it was my thought to tap into the load wire and ground wire running to one seat, then basically tee off to the second seat. The relay and the fuse are rated high enough to take simultaneous current from both seats.

Please let me know what's correct and what's incorrect about my thinking. I can provide photos if and where it may be helpful.

I want to make sure this is done correctly, and this seemed like the place to go for info.

Thank you in advance!

By the way, if this is the incorrect subforum for this question please notify me or move it where it's most appropriate.

Here are some pictures of the seats and the wiring I'm talking about:
Seat:


Control buttons (the two top ones light up):


Red and brown wire from seat (the blue wires are for heat, ignore those):


Auxiliary fuse box on the car:


and here's a shot of the car for reference :)

I have Recaro's in my DD. They have the same functions as yours do, but my controls are different, and my seats were new in about 1990.

My seats have the same one red, one brown wire. I connected the brown to earth, and the red to a Hot at all times B+ source. Here's where it gets interesting: My seats seem to know if there is a butt sitting on it. I can leave the heater switch ON, and the battery doesn't go dead for days; only the pilot light in the switch is illuminated. My heaters may not be functioning correctly, I can barely tell that there is "heat", but they do do something.

Your blue wire looks like a fuse holder on one of them. And a "Y" tap on the other blue; I'm not clear on how those wires are "the heater". So what. If blue IS the heater, I'd still just wire the heaters to the same source as the red. If I were doing your install, I'd connect the seat power to a HOT in RUN or ACCY (power windows or retained accy buss) and call it done.