Guide: Retrofitting Second Generation Seats into a First Generation MINI
Posted by Andy Laguna-Aponte on
The second generation MINI Cooper launched in 2007, and with it came a host of upgrades over the discontinued R50/R53 generation of hatches from years prior. Though a matter of subjectivity, one common complaint from first-generation MINI owners is that the seats in their Coopers are rather unsupportive and aesthetically dated. Since the release of the R56, owners have caught on to the fact that the second generation of seats fit right into the cabin of a first-generation MINI. There are posts published on the internet with information on how to properly retrofit the set of seats, so we decided to follow their guides and record our own experience with this project on our resident R53. Credits go to NAM user ih8cornnuts for a detailed write-up linked here: https://www.northamericanmotoring.com/forums/interior-exterior/258753-r56-seats-into-my-04-r53-installed-and-pics.html.
It is important to understand not only which seats MINI has to offer when it comes to colors and materials, but also which seats you can and cannot use when considering undertaking this retrofit project. Since the front seat rails between the first two generations of MINIs are virtually identical, you can choose from any pair of front seats from an R55/R56/R57 to swap into your MINI. However, if you are looking for a matching set of second-generation front and rear seats for your first-generation R50/R53, you must bear in mind that you can only install a set from an R56 or an R55. The rear seats on the convertibles are different and thus may require more modifications to ensure proper fitment.
That being said, there are many colors and materials to choose from when looking for your new seats. We chose a set of "Punch" Carbon Black, heated leather seats for our MINI.
T8E1 R56 Sport seats
Before any kind of installation can happen, it is important to note what this retrofit entails. In essence, we are taking the plugs from the R56 front seats and converting them in such a fashion that they will work with the existing connections on your first-generation MINI. We will also be swapping the seat belt buckles on the front seats. As for the rear seats, we will be modifying the brackets where the seat backs mount on the quarter panels so they can fit inside the existing holes. These are the most tedious aspects of the installation.
Here are the materials we used to perform this retrofit:
- Wire cutters
- Wire strippers
- Die grinder
- Die grinder bits
- T40 Torx socket
- 10mm socket and accompanying ratchet
- Very small flathead screwdriver
- Paper clip, or a small wire of similar nature and size
- Zip ties
- Vacuum cleaner
- R56 center seat bracket
- R56 outer plastic seat bushings
- R53 seat belt buckles
- Safety goggles
Removing the old seats
So we've picked out our seats and our materials. Now it's time to get started with the installation.
First, remove the negative battery cable from the battery. This is a crucial step because if you do not disconnect the battery, you will have the airbag lights on your dash light up. The only way to clear them thereafter would be with access to dealer-level software.
Next, you can remove your existing seats. There are four T40 bolts for each front seat that bolt the seat rails to the chassis. Removing them allows you to flip your seats to access the connections under the cushions. Carefully unplug each connection.
The rear seats are composed of two cushions. The bottom portion of the seats can be removed by simply lifting them off their clasps from the chassis. The seat backs are held in place by a bracket that joins the two. First, remove the 10mm bolt that secures the seat backs in place within the bracket. On the other side of the seat backs, there is another bracket that holds the cushions by way of a plastic bushing. Fold your seats down. Now you can lift the backs out from the bracket one at a time, paying attention to the placement of the metal ends on the seat backs and the plastic bushing. Align the two and you can lift the seat backs out from the car.
Now you have access to the center bracket. It is bolted to the chassis using three 10mm bolts.
There was considerable debris on the carpets and on the plastic interior panels we couldn't have access to with the seats in, so we took the opportunity to vacuum and wipe down some of the interiors.
Little bit of clean-up action
Working with the front seats
The reason why this retrofit isn't plug-and-play is because the connector bodies used on the R56/R55 are not the same as they are found on the R50/R53. Thus, to retain the functionality of working airbags in a first-generation MINI, the connector bodies from second-generation seats must be de-pinned and then moved to connector bodies from your existing seats.
Take a look under the second-generation seats. BMW put all of the connectors into a single yellow housing. Slide it out from the tracks it's held in place by and then slide the black plastic piece inside of the big housing out.
Yellow housing for connectors
Slide retaining clip outwards to expose connectors
Once you do that you can access the individual connectors housed within the yellow body. Slide each one by one. You can toss this yellow housing away.
Now that you have these removed, it's time to de-pin the airbag connector. They are yellow and brown wires. You can do this using a very small flathead screwdriver. There are marks where you can press the pins down to be able to unlatch them and pull them out from their grey housings. You should now have two wires (one yellow and one brown) with copper ends hanging loosely from the bottom of your R56 seats.
Now that you've removed the pins from the R56 connectors, you need to remove the yellow connector bodies from the R53 airbag connectors. First, cut the wires that go to the connector. Now you have a free connector body. Then you can press out the grey connector inside the yellow body. You can do this by using a paper clip. Push the paper clip through the R53 connector where the wire goes through. You should now have a yellow connector body free from its inner grey connector. Slide the pink retainer clip out and save it, because it will be reused.
We now have a free grey connector. Remove a decent amount of sheathing from the yellow and brown wires hanging loosely under your R56 seat. This is because you want to have some wiggle room so you can properly insert the R56 pins into the grey and yellow R53 connector body units. Take the pins, and keeping in mind orientation and placement, slide them inside of the grey connectors. Make sure the metal retainers click into place to ensure they will not be slid out by accident. Once both pins are in, make sure to place the pink retainer clips back to secure the pins further. You can now slide the grey connectors back into their yellow housings. Congrats, you've finished the connector body swap!
Next, it's time to swap over your existing first-generation seat belt buckles onto the second-generation seats. You must swap the buckles over because the first-generation belts will not work with the second-generation buckles. Remove the Torx T60 bolts from each buckle, and disconnect them from the underside of your seats. Take that same T60 bolt and use it to fasten the R53 buckles into the R56 seats. It threads right in. You'll see a piece of aluminum sticks out from your R56 seats near the buckles. Without modifying this piece the R53 buckles will not seat properly into the sides of your new seats. We opted to bend the aluminum with a pair of pliers and hammer it into shape with an adjacent piece of metal. Some blue Loctite on the T60 bolt will ensure your buckles will keep in place under use.
T60 Torx bolt for buckles
If your R50/R53 is newer than 07/2004 there's a high chance your MINI was equipped with the aforementioned occupancy sensor in the passenger's seat. Luckily, you can take this wire from your existing R53 seats and reuse it in your R56 seats to prevent the occupancy light on your dash.
Occupancy sensor plug to seat harness
Occupancy sensor plug to seat
You'll find the wire connects right up under your new seats.
All plugs connected
So now all the connections have been made and your seat belt buckles are swapped! Make sure to take a couple of zip ties to tidy up the wiring underneath your seat. The front seats are ready to bolt into the car.
Mounting the rear seats
The rear seats are a little less complicated. The bottom portion of the R56 rear seat clicks right into place using the existing latches. Simply press hard enough on each side of the cushion and you'll feel the latches click. Before you install it, however, it is a good idea to install the backrests.
The R56 bottom seat cushion simply latches into place.
The backrests are a little more complicated to fit. The brackets where they mount to the quarter panels on the chassis need to be modified. The metal inserts on the new seats are larger and so you need to drill out the holes on the metal brackets. You can use the plastic bushings as references for just how much you need to drill.
Metal seat insert
Exposed aluminum seat bracket where metal insert and plastic bushing fit into.
To drill out the holes we used a pneumatic die grinder with an assortment of bits. You may have to trim the plastic around the top hole, and even the plastic between the two holes.
Pneumatic die grinder
Assortment of bits
It's a good idea to take a fine marker and try to cut within the bounds of your markings on the aluminum plate where the seat inserts mount.
There will be a lot of debris formed from the shaving of the aluminum brackets. Make sure you are wearing the proper attire to avoid getting the shavings in your eyes and your skin.
R56 center seat bracket
Once you have cut enough for your seats to slide in, install the R56 center seat bracket. It is, again, held in place by the same three bolts. To install the rear seats, slide the ends into the shaved aluminum brackets. Then, with the help of a flathead screwdriver, insert the other metal ends into the center bracket. Two metal retainers need to be moved so that the seat backs can lock into place. Finally, move the seat backs and ensure they lock into place with your existing R53 seat back latches. Install the bottom cushion, and your rear seat conversion is done!
All buttoned up!
They see me foldin', they hatin'!
Now you can go ahead and bolt up your front seats.
There is a way to keep the heated seat functionality, if your MINI was optioned so and if your replacement seats do support it. However, as of this writing, we have not delved into that aspect of the retrofit.
The first-generation MINIs have a control unit for the heated seats in the switch panel. Second-generation MINIs have one under each seat. There is probably a way to bypass the control unit in the switch panel to be able to run power to the ones under the R56 seats. We'll update this post once we have got that working.