Interior 2nd Gen How to: Installing aftermarket seats R56 - Motoring Alliance Exclusive!!

Recently I installed a pair of Sparco Evo2 Plus seats in my Mini. I thought that I would put together this write up in hopes that it might be a little easier for someone else.

The information below I have gathered from a number of sources and is accurate to the best of my knowledge.

First the safety devices involved with the seats in an R56:

Driver's seat:

Airbag - There is an airbag located in the front drivers seat. This can be bypassed with a 2.3Ohm resistor.
Seat Position Sensor - This sensor contains 2 pieces, an electronic sensor and a magnet. This is used to determine how much force is used to fire the steering wheel airbag. The sensor is located on the sliding portion of the stock rails and the magnet is located on the fixed portion below it.
Seat Belt Sensor - Used to determine if the seat belt is fastened
Seat Belt Pre-tensioner - Applies additional tension on the seat belt during a crash.

Passenger's seat:

Airbag - See above
Seat Belt Sensor - See above
Seat Belt Pre-tensioner - See above
Seat Weight Sensor - A weight sensor with a Hall Switch located on top of the cushion but below the seat cover. Used to determine if there is a passenger in the seat.

Removing the seat:

There are 4 torx bolts that bolt the seat in place. Slide the seat all the way back revealing the front 2 bolts. Then slide the seat all the way forward to reveal the rear bolts. This is also a good time to raise the seat all the way up, later you will need the clearance to remove the seat from the sliders. The front bolts are seen here:





After you get the seat un-bolted from the car you will notice a rather large yellow plug:



This large plug actually contains 3 smaller plugs. On the passenger side they are: the airbag (the yellow cable), seatbelt/pre-tensioner (the other gray connector), and the seat heater/weight sensor (the larger black connector). Slide the individual connectors out of the larger yellow one. It should look like this:



Removing the stock seat belt and pre-tensioner:

Both of these items come off as one piece. A single torx bolt removes it, picture here:



Airbag:

A resistor needs to be put in place of the airbag so you don't get an airbag light. The plug used on the end of the airbag (yellow cable) has a special plug that shorts out the connector when it's unplugged. Seen here:



In order to properly measure the resistance across the airbag in order to duplicate it, you need to separate the short from the actual connector. I used a piece of cardboard like this:



My airbag measured 2.3Ohms. To replicate this I used a 2.2Ohm 1/2 watt 5% resistor. I then cut the airbag connector off the end of the airbag (seat side plug) and soldered the resistor to it. I insulated the legs of the resistor with heat shrink to prevent a short. Seen here:



and then put a larger piece of heat shrink over the whole thing. Seen here:



After the whole piece is assembled, I double checked the resistance one last time.

Removing the seat from the stock sliders:

Using a 13mm wrench remove the 6 nuts that attach the seat to the stock sliders. 2 nuts on the outboard side and 4 on the inboard site, this is where you will be glad you raised the seat.

Removing the weight sensor:

The next task for the passenger side is to remove the weight sensor. Note: this is pretty much a terminal procedure (if you thought cutting the end off the airbag sensor.... it get's worse). First remove the lever that controls the seat height, pop off the plastic cap to reveal 2 torx screws. Seen here:



With the lever removed you can now remove the side trim carefully. After this, start removing the lower seat cover. After you have the surrounding edges separated you will notice that the seat cover is held in place with a series of metal rings. They attach a plastic rod in the cover to a metal rod embedded in the seat cushion. I used a pair of wire snips to cut the metal rings allowing me to remove the cover from the seat cushion. (sorry, I didn't get any pictures of this, but it should make sense when you see it.)

This will reveal the weight sensor looking like this:



And the control module looks like this:



I removed the weight sensor and installed it into my new seat. When you remove it you will notice there is a thin connector that runs the exterior, be extremely careful not to crease it and cause a short. You will also notice that there is some extra material holding it down to the stock seat. I trimmed some of this back to help it fit into my new seat. Again, you need to be extremely careful you are just cutting fabric and not the exterior connector. In the stock seat the control module is towards the rear of the seat. With my Sparco's this will not work if you plan on using the sub-strap for your harness (which I do). To get around this I turned the sensor around and put the control module towards the front, as seen in the picture below. I also put some double sided sticky tape down to try and keep it from moving around too much.



Another issue I had was what to do with the electrical connector. I didn't want to just drop it down the hole my sub-strap comes through because I was afraid it would damage the wiring.... so.... I drilled a whole in my brand new seat to be able to pass the connector under the seat. I am not totally positive this is the best option, but I couldn't see any other way.

Bracket installation:

I purchased the Brey-Krause brackets that are really designed for the R53 (BK #R-9273). These brackets kinda fit, I had to slot a couple of the holes so that they would bolt onto the stock sliders. Note: the steel used for the BK brackets is pretty hard, I used a carbide grinding bit making frequent stops to a cup of water to try and keep the bit cool.

The biggest issue I ran into with this is with the fitment of the brackets. Slotting the holes so that the brackets fit onto the stock sliders was not that big a deal, but after I had everything bolted together the angles for the brackets were off slightly from the holes in the floor. Like the brackets were toed out too much. I got them bolted in, but it was more difficult that it should have been.

The seats go together like this: Floor --> Stock sliders --> BK Brackets --> Seat.

Stock Seat Belt:

After getting the brackets bolted to the stock sliders I bolted the seat to the bracket. The next step is to re-attach the stock seat belt mount to the BK brackets. There are no existing holes to do this, so I drilled 2 holes to attach the seat belt receiver. One larger hole actually holds the seat belt in place, and a smaller one that keeps it aligned. Take careful not of where the bottom of the seat is in relation to the seat belt bolt. It gets pretty close. Mine looks like this:



Final Assembly:

After getting everything bolted together I re-assembled the large yellow plug and attached it back to the underside of the seat with some velcro with adhesive backing. I also reinstalled the heater module from my old seats. Not the actual heater, that connected with 2 plugs that have been removed, just the module. I was unsure if having this disconnected would set off any type of code and just thought it was easier to just reattach it than worry about it. Here is a picture of the underside of the seat with everything ready to go:



Now I was ready to bolt the seat in the car. After attaching the seat and reconnecting the large yellow connector, I started the car and hoped that I didn't get any airbag lights, which I didn't!!! I then tested the seat belt sensor as well as the weight sensor and everything is working. Here are some pic of the finished seat install:





Note: the photos here are all from the passenger side installation. The only difference from the drivers side is that you don't have to deal with the weight sensor and you have the added seat position sensor. The seat position sensor is already mounted on the stock sliders, so if you keep them there is no issue there. The forward magnet that mounts on the fixed portion of the slider got in the way of the Brey-Krause brackets that I used. I cut the plastic bracket off with my dremel and attached the magnet directly to the side of the rail with some double sided sticky tape. I am still looking for a more permanent way of attaching that, but it should hold for a while.

 

Thanks!

I was initially concerned about the seat belt height as well. For the record, I am 6'5" weight 210 with a 34" waist. The belt seems to snug up pretty well. I have hips that stick over the top of the seat. If one was more concerned with this you could easily unbolt the bottom of the stock belt and route it through the lab belt slots. You could do the same with the receiver.

 

I know the description looks correct, but the part doesn't look anything like the seat sensor. From talking with the dealer they indicated it was only sold with the whole seat cushion and cover. After talking it apart that would make sense with what I saw.

Hopefully it will be the correct part... oh, the dealer also said something about the sensor being coded to the vehicle, and it would require me to pay them to re-code the weight sensor.

 

It definitely is different..... but it is definitely also a weight sensor. Doesn't really make sense that they would manufacture two different parts that do the same thing.

I think the only way to know for certain, would be to plug it in and see if it 1) throws a code and 2) actually detects weight in the seat. It's hard to tell from the picture how large it is, but it looks a little bit smaller... which is a good thing if you are trying to fit it into a fixed back seat.... I think I remember that you are getting a set of recaro's, leather with red stitching? the pic that I saw looks awesome!

Let me know how it turns out.

 

I will have to double check, I can tell you that that steel that the BK brackets are made out of is super hard. You are going to need a carbide or diamond tipped bit to get through it. Two actually, one for the bolt that holds the actual bracket on and another for the bolt that keeps it aligned.

 

The bit I used for the main bolt was a 3/8" carbide bit. I used a 10mm bolt, I think the length was 30mm but I can't remember for sure.... I know I purchased two sizes, the longer one that I did not use was the 40mm, I am pretty sure the shorter one that I used was 30mm. For the smaller bolt, I used a 1/4" carbide bit and a 6mmx30mm bolt.

 

Sorry to hear that... but glad I didn't tear apart my passenger seat for nothing. Will the dealer take it back?

2.2Ohm not KOhm. I got mine at Frys, don't know if you have those where you are at. I would really have thought that Radio Shack would carry those. They are small, but not out of the ordinary.