Seat Motors - Relays - DPDT switches

[Porsche_911s]

I have a couple electrical questions that many of our resident electrical engineers can probably answer off the cuff.

Does anyone know how large a relay it would take to operate a Porsche seat motor? Would a 12vdc / 10 amp relay supply enough amperage?

On Porsche powered seats that are controlled with the switches located on the side, do these DPDT switches operate relays in the seat / motor, or do they switch the power required to operate the seat motor?

I am attempting to bypass the "seat controller" on a set of newer Porsche seats. These questions will help me determine if I need to install relays, what type of relays, or if I need to install new switches.

I am currently looking at the following relay:
http://www.aquahub.com/store/12voltspdtrelay.html



As far as wiring, I wire STSP relays all the time but I have not wired a DPDT relay before. Do these relays act similar to DPDT momentary switches?
(ONm) (OFF) (ONm)

To make things more complicated, wiring the DPDT relay to a Porsche seat switches might be more fun than I can handle...

[RoninLB]

I installed power seats into my non-powered car.

I ran a new 12 ga wire hot and ground from battery to car electric side of seat electric connector.

I used a marine circuit breaker on each seat.

No relays

Amp fuse should allow around 70% of load.
ie: a 10amp fuse for a 7amp load.

[Porsche_911s]

Thanks for the reply!

Since both seats are powered, do you think one 10 or 12 gauge wire is enough for both seats? I'd just use a power distribution block under one seat.

My main questions are how to get around the seat controller for the new seats. The passenger side has two wires but the drivers side has 7 connectors!

Drivers Side


Passenger Side

[RoninLB]

my passenger plug has a red, black, and brown.

I didn't look at drivers seat but I think it's same.

Both my seats have only 2 momentary switches. I don't have the 3 button or a seat heater. Your 7 wire driver's seat is probably like that.

the 7 wire should have the red, black, and brown. Play around with the 3 wires and 2 wires jumped from battery till you get your new seats to work.

My install was run individually from 2 luggage compartment circuit breakers. I probably could have run 14ga for each. I guess that each seat motor is only about 5-7amps when motors are new.


"My main questions are how to get around the seat controller for the new seats."
--------- this means the seat electric plug, right?

[RoninLB]

Pelican's electrical diagrams


http://www.pelicanparts.com/911/911_Parts/911_electrical_diagrams.htm


ps: I couldn't find the electric diagram in Workshop Manual

[Porsche_911s]

Each motor has 4 wires, then the seat switches have 6 wires, there are a couple more for seat belt or other accessories. These all plug into an external seat controller.

I am just trying to figure out the best way to not have to purchase this controller. I did not see any wiring diagrams for 996s or Boxsters, these seats are from a '99 Porsche.

The passenger seat does not take a controller but only have the + & - wires. Which is what why I posted. Hopefully I can figure out how to wire the drivers side seat to bypass the controller.

These are 8 way seats with 2 switches. One switch is a 4 way switch and the other is a 2 way. But I believe the switches are identical on each side. So either the switch is able to flip that much current or the are relays in the motor or seat that I cannot see.

If I use the Porsche seat switches, I guess I can use a multi-meter to figure out which wires are paired up.

[Porsche_911s]

I finally got to take the seat switch plates down and take a closer look at how they are wired. The passenger side and the drivers side appear to have identical momentary rocker switches. However, the switches on the passenger side have larger gauge wire going directly to the leads on the switches. The drivers side has a printed circuit board and does appear it will handle the load that is needed.

I could easily duplicate the passenger side wires going directly to the motors. But I cannot tell how the + /- wires are distributed on the passenger side so I can duplicate it on the drivers side.

Each switch appears to have two large posts that are connected to the + / - wires of the motors. Then, there are three smaller posts. I guess powering the passenger side and getting the multimeter out is the next step.

[burgermeister]

If I understand your project correctly, I think you need something other than a dpdt relay ... the seat switches are not rocker switches, they're actually momentary contact 3-position switches, with the unloaded position being "off". A DPDT relay would always be either in the "seat moves up" position or the "seat moves down down" position, never in the "seat is adjusted and not moving" position.

Or I misunderstood ... in which case, never mind!

[Porsche_911s]

No you are correct, as I listed in the first post, (ONm) (OFF) (ONm). The relays are only to control the power flow, the momentary switches would activate the relays.

The seat switches are momentary switches but the current configuration on the driver's side will not work as is. I might be able to solder new wires but it will be tricky because they are extremely close in some spots. Using the multimeter & checking for continuity, I found the following for the Porsche seat switches:




Thanks for the reply, I'll keep working on it.

[burgermeister]

Aaahh, I think I get it - 2 relays per motor, one for one direction and one for reverse direction?

[Porsche_911s]

Well that is what I am trying to figure out. If I can figure out how to just wire the Porsche switches it would be much easier. If I can replace the wires, it will be some tricky soldering.

From what I can tell on the switches, all the wires to the motor are grounded when off. When a switch is flipped either direction, one wire is ungrounded and power is applied. Easy concept, I may just need to get some better tools and give it a shot.

[RoninLB]

keep the info coming for the archives.

[Porsche_911s]

I think that is about as much useful information that I can provide.

The 996 / boxster seats are too high to use in an older car. In order to mount them with my sliders, I am taking off all the electronics except the motor built into the back of the seat. I am going to fab some "L" brackets to mount to my sliders and then mount them to my car frame. Doing this with the seat bottom off should not be that hard. (I hope)

With 6 way my idea might have worked, but with 8 way you are dealing with a powered track inside of the seat sliders. Unless you are short, this puts you up too high.

[AJA625]

Just wondering if you figured out the wiring for the drivers side; I installed passenger side w/out a hitch but now I'm stuck. I did not notice the driver's side was completely different (memory + heated)...I hate to drive around with different type of seats in my car.

Thanks,
Fred

[Porsche_911s]

I wanted the seats lower and decided to take off all motors & seat rails. Lost about 20 lbs per seat in the process.

I can tell you that it will never work unless you hook up relays or replace the switches with something that can handle the current. The printed circuit board will never handle the load.

Good luck!

[Oregon Cab]

I am about to pull my drivers seat and pop in a power sport. Don't want to disconnect my battery since my stereo will lose all of its memory. Can I just pop the fuse out of the fuse box, I think its the second one from the left?

----
Did it.

[RoninLB]

when I installed power seats I used 12 ga wire run to a double circuit breaker run to the battery.