Elmiko

I found a neat multi-directional switch sold by Mouser Electronics which made a nice replacement for the worn out seat switches on my '87 928. This switch fits perfectly through the holes in the outer bezel of the switch assembly and is shallow enough to allow room for the leads to snake through the tight passage to the underside of the seat when the bezel is reinstalled. Since the switch contacts are rated at only 50mA, I used 2 pair (one pair for up/down and one for reverse/forward) of Panasonic SPDT miniature automotive relays to toggle polarity to the leads of the seat motors. These relays are about the size of a sugar cube but their contacts are rated at 20 amps. The relays are about $2.50 each,and the multi-directional switch is about $25, so the cost of replacing one old switch is about $35. I didn't use the center switch, but I guess it could be used as the seat heater switch if you're lucky enough to have ones that work. Finally, the reason there are so many leads on the ribbon cable is because each switch key contains a red LED, which I didn't see any use for. If anyone's interested, I'll be happy to post Mouser part numbers.

FLYVMO

Yes please
A part number would be greatly appreciated. Nice find!

Cheers!
Carl

Alan

For memory seats that already have relays 50mA should be enough as is.

These do look nice! all LED's illuminated all the time with ignition/interior lights would be nice

About $25 @ Mouser - Mouser Part# 107-5D02-BKARXRRRRW2

http://www.mouser.com/ProductDetail/...vei1QgU6SRY%3d

Alan

FLYVMO

Awesome, thanks Alan!

Cheers!
Carl

Elmiko

The Mouser P/N for the Panasonic relay is 769-CP1-12V. I don't have the memory feature, so the original switches went directly to the motors. I guess they don't use a a lot of current, but I'm sure it's still more than 50mA. And since the switches themselves are SPST, you need a way to change polarity. For the mechanical part of the project, I removed the plastic assembly that the original switches snap into and put it aside. I then traced the outline of the outer bezel on a piece of 22 gauge sheet metal to make a mounting plate the new switches would snap into (they have locking tabs). After cutting the plate out, I the used a 1 5/8" hole saw to drill the holes for the 2 multi-directional switches (only 2 since I don't have lumbar support) and I Dremeled the rectangular opening for the heater switch. Lastly, I used a piece of black adhesive leatherette on the outside of the plate so that no shiny metal would show-paint could be used too. Since my seat heaters haven't worked for years, I desoldered the leads to the switch and snapped it into my mounting plate just for appearances. I removed all the leads and relay for the heaters and stored them away for the next owner. I soldered everything point-to-point and encased it all in heatshrink, but someone who can make a PC board to mount the relays on and can fabricate with Molex connectors (like Paul Champagne does with the window switches) could really make a nice neat little package.

Kevin in Atlanta

Pictures of them installed would be nice.

MjRocket

Yes pics Please.

Elmiko

Here's what the new seat switches look like installed-no huge difference in appearance, but I wanted to stay close to the original look.

Ducman82

Now we need a cheap switch for the early comfort seats....

Alan

Looks great - you did a good job! looks better than stock. Now other than seat heaters what would those on/off switches be good for...?

Alan

depami

Massage vibrator.

GeorgeM

I thought you need a coin slot for that....

M. Requin

Thank you, thank you, thank you!!!

Alan

Actually yes that seem popular on luxury cars these days - Great idea: Seat, Back, Lumbar only

Alan

PorKen

Agreed.

Center button - memory positions - 1, 2 (, 3)