BMW Cup Holder and Console LED Lights DIY (with lots of pictures) DISCLAIMER: I did this in my 1995 318i E36 using the 1996-1999 style E36 Modular Cup holder/Storage Tray/Coin Box Console. However, the ease of the DIY makes it applicable to any other BMW from any years, as well as other brand vehicles that come with similar style cup holders and consoles. It is a monster write up for what is basically a quick, simple and cheap DIY with a highly OEM cosmetic and functional appeal. INTRO:
If you ever did an extended road trip where you have long stretches of highway to cover after dark and your only passenger is a cup of coffee and you often had to fidget to place the coffee in the miniature E36 cup holders and often end up spilling some of it, then this easy and cheap DIY is for you. Even if you want an easier time finding stuff like keys, money, credit cards, etc... in your Storage Tray or Cup Holders at night whiles driving then this DIY can also work for you.
BACKGROUND:
I’ve been meaning to do this for sometime now, but needed to find the time and the best method of installing cup holder lights in the console area. Originally the idea came to me a few years ago when I first discovered my car had wiring beneath the console for a Telephone, Aux Audio Input and a small filament bulb that I assumed was there to light up the console area.
Naturally, after 10+ years in the car the bulb was blown so I went to the dealership to replace it hoping that I could have use the light for my cup holder. BMW wanted $12.50 plus tax for what is nothing more than a single Christmas Tree light bulb (that you can normally buy for 99 Cents for a box of 100). I said no to them and started thinking of another way of doing it. I went online...
Over the years I found a few DIY sites showing different methods, the best was this one;
BMW E46 Illuminated Cupholder DIY
Here this guy installs two 20mm disc LEDs into each holder in his 2004 325xiT wagon. This method is very OEM and clean looking and was my first choice. Sadly, the 20mm LEDs he used proved near impossible to buy since the USA company that imports them from China no longer exist. So short of taking an airplane to Shanghai that DIY was not going to work for me. Also the guy used a Dremel Set and spent time soldering the complicated micro LED circuitry to finish off his project.
There are a few more Cup Holder LED Light DIYs at the Honda Civic and Dodge Charger Web Forums that show folks hot gluing smaller 3mm - 5mm LED bulbs (from 2 bulbs up to 10 bulbs) into tiny holes drilled into the console cup holders. And Electric-taping the wiring together under the 12V outlet. Although their techniques were sloppy, the idea of simple wiring with smaller holes and LEDs was cheaper, quicker and more flexible for me. Also messing up didn’t mean having two big 20mm holes to worry about in your console.
DIY PREP:
So I went on eBay and purchased a set of twenty 3mm Orange/Amber LED complete with wiring from a Hong Kong company called Sure Electronics. They ship within 2 weeks, but their LEDs were quality and the entire set worked. (you will hear from some people that LEDs come not working) The LEDs cost $9.99 total with shipping. I also purchased 2 spools of 20 Gauge wiring in RED and BLACK colors from Radio Shack for $6, as well as Heat Shrink for $3 and wire connectors for $1.99. I already own a power drill and Crazy Glue was the only other expense.
My 1995 BMW 318i came with the older style E36 Cup Holder which sucks because not only are the cup holders extra small and useless but everything is stationary so you cannot move the coin holder and cup holders around like you can on the newer 1996-1999 style E36 Modular Cup Holder. I wanted bigger holders and a storage partition instead of an ashtray so I went back on eBay and won a brand new E36 Modular Cup Holder with Storage Partition for $50-shipped. I then managed to sell my old one on eBay for about $50. So I broke even.
Here is a
Before picture of my 1995 early E36 style Console
That said this project only cost me about $20 to $25 for the LEDs and wiring and crazy glue.
TOOLS:
Power Drill w/ 2mm or 3mm drill bits
Small philips star point screw driver
Crazy Glue
Wiring Stripper/Crimper or Scissors
EQUIPMENT:
Spool of RED 20 Gauge wiring
Spool of BLACK 20 Gauge wiring
Heat Shrink
Wire Connector Clips (2 sets)
THINGS TO HAVE NEARBY:
Your Car’s Battery or a 12V Battery (for testing the bulbs and connections)
Small Needle Nose Pliers
Scotch Tape or Electrical Tape (for temporarily holding the bulbs in place whiles the glue dry)
THE REST:
The Modular Console Base w/ Cup Holder Modules and Coin Box
($99 at the dealership or $40+ on eBay-if you buy a used one off eBay just make sure the cup holder modules' 4 spring grip finger slats for holding cups are all still in place since usually they are sold with one or two broken off. If you get a broken one you can easily replace it by buying new cup holder modules which cost about $15 each at the dealership) 
The Storage Partition Tray w/ Parts Number in the picture
($14-$18) 
Set of 20 3mm LEDs ordered for $9.99 w/ free shipping from Sure Electronics in Hong Kong via eBay (they also sell under the eBay Seller's ID: eylane). The important thing is to make sure the LED bulbs are pre-wired with power (RED) and ground (BLACK) pigtails. Also stay away from Aftermarket Brands and Auto websites selling these exact same bulbs minus the wiring and nothing else in expensive "LED Kits" that cost $25 to $40 for 5 bulbs.
LETS BEGIN: 1. Begin by removing the two Modular Cup Holders and Storage Partition tray and The Coin Box as well. If your Modular Console came with the Ashtray then you can buy the Storage Tray on eBay (I got mine there for $14.00) or the Dealership for $18.
2. Find the 4 finger slats that spring-grip the cups and look at the space right below each one. Here is where you will drill your 2mm or 3mm holes. I put holes under each slat (four slats, four holes, four bulbs) to balance it out, but you can only drill less holes if you want to use less bulbs. During the project I realized that 4 bulbs may come out brighter than I wanted or stick out and be obvious, but because the 3mm bulbs are tiny and the way they are placed under the spring-grip finger slats they bulbs don’t stick out and the light emitted from each bulb doesn’t shine above the console-meaning it wasn’t bright or harsh at all, but just right.
3. After drilling the 2mm holes, you can used the screw driver to widen the holes just a little bit to squeeze the 3mm LED bulb thru. Too small is okay but you don’t want the hole too big. So be careful if you use a 3mm drill to not to let the hole be bigger than you want. Also the bulb’s shape is similar to that of a Bowlers Hat, where the top is round and then the base of the bulb is wider with a slight brim or ledge. This is good because you can squeeze the 3mm bulb into a smaller 2mm to 2.5mm hole and not have the bulb fall thru into the cup holder.
4. After you do the Cup Holders you can start with the Storage Tray Partition. I only drilled one hole and used one bulb, but you can use more if you need to. Center the hole and begin drilling.
5. Connect your wires. For the first Cup Holder connect all the RED wiring and Heat Shrink them to a 12 inch strip of RED wire from your 20 Gauge spool. Then do this for all the BLACK wiring as well. Test at the 12V Battery to make sure everything works. Then repeat for the second Cup Holder. When you are done you should have two sets of RED and BLACK wires that power the two Cup Holders. Test everything on your 12 V Battery. Now do the Storage Partition. I only had one bulb with a RED and BLACK wire from the Storage Partition. I extended these two wires with a 12 inch 20 Gauge RED and BLACK wiring via a Heat Shrink. Test with a 12V battery.
Now you should have three sets of RED and BLACK wiring; the Cup Holder 1 set, Cup Holder 2 set and the Storage Partition set. Splice all the 3 BLACK wires together and Heat Shrink it onto a BLACK 6 inch wire from your 20 Gauge Spool. Do the same for the RED set. When done you will have only one RED and one BLACK wire that powers both Cup Holders and the Storage Partition. Test them on your 12 V battery to see that everything works.
6. Splice All the RED wiring and BLACK wiring together onto one branch that will connect to the POWER and GROUND wires under your console. This part is pretty straight forward If you just picture the branches of a tree coming together at the trunk. I found heat shrinks to be very easy to use and quick for this DIY. Be sure to keep testing at the 12 V Battery to be sure everything is working each step of the way. LEDs are pretty durable and long lasting but you never know and you don't want to finish a project and flipping the switch to see only half your bulbs light up. When done you can test everything again at the Console Bulb's power wires found under the console. Just insert the tips of your RED and BLACK wire into the tiny holes of the bulb's harness socket. One wire will be red/grey for power and one will be brown for ground.
7. Glue time! This was really the hardest part; deciding the best glue to use. I didn’t want to Glue Gun the whole thing because that looked very messy in the other DIY that used that technique and also I’m not sure how easy it would be to change the bulbs or reverse the project after you spackle the whole thing with huge gobs of plastic glue. I decided Crazy Glue was the cleanest and quickest way to get the bulbs to stay where they should. Also it would be easy to pluck out the bulbs when and if the time came since I only used a tiny drop of glue for each bulb. Start with the Storage Partition since it is a square, flat object and easier to see what you are doing. Put only a drop on the bulbs brim (close to the base right before the wires) and wedge it in. Use the tape to hold the bulb in place. Then do the same with the Cup Holders. With these the tape is necessary since the web of wiring will all pull and tug every time you move to another bulb on the same harness. Give yourself time to make sure the bulbs are well secured. Allow 20-30 minutes for the glue to properly dry.
8. Wire Connectors! Apply the 2 female connector leads each to the RED and BLACK wire coming from to your Cup Holder and Storage Tray. The female connector leads are tricker to apply and I rather do this with the RED and BLACK wires from the Cup Holder and Storage Tray inside my air conditioned home. When done with the female leads go the car and find your console bulb. (Most E36s have these old school filament bulbs under the console that was factory wired for an Ashtray Console Light and if your car is over ten years old chances are this bulb is already blown. My BMW dealership wanted a whopping $12.75 for the replacement filament bulb, which is how I decided on this DIY to begin with).
Snip the wires that power this bulb (one should be Brown for Ground and the other Grey w/ a Red Stripe for Power) and apply a male connecter lead to each wire. The male leads are way easier to apply hence why I saved them for the car.
When done, go back inside to your Cup Holders and Storage Tray. The glue should be dry by now.
9. Reassemble the Modular Cup Holder 1 and 2 and the Storage Tray Partition into the Modular Console base frame! Okay,
STOP! This bit is important; if you made it to this step and you begin replacing the newly wired Cup Holders and Tray back into the Modular base frame you will quickly realize that it appears that the Modular base frame's section cross bars and all the wiring prevents you from getting them back onto the Modular base frame and now you are wondering why you didn't glue the LED bulbs/wires onto the Holders and Tray after reassembling the Console. Don’t panic, like I did, because this is good thing and the wiring really does not prevent you from replacing them into the Modular base frame. If you had glued the bulbs onto the Cup Holders and Storage Tray after you reassembled the Console then the wiring would have definitely prevented you from getting the modular parts
off the base frame making the process of customizing your console or removing a modular part of the console impossible.
All you have to you have to do is make one end the front (where the Cup Holders go) and the other end the rear (where the Storage Tray Partition goes).
A. Starting at the front end hole slip the Storage Tray sideways through from the top all the way out through to the underside of the base frame. Let all the wiring follow.
B. Now bring the Storage Tray back up thru to the top at hole at the rear end and connect the Storage Tray in it’s place. All the wiring for the Storage Tray should be under the Storage Tray and going from the bottom of the StorageTray to the first hole front end and up thru to the top where it meets the Cup Holders.
C. Now insert the first position Cup Holder and let the bulk of wiring for it sit at the bottom right below it. You will see that there will be only two wires (RED and BLACK) left that join the two Cup Holders and you can easily run these two wires between the cup holders above and in between the Modular base frame's cross bars.
D. Now insert the second position Cup Holder with the bulk of it’s wiring sitting below it and the two wires running above the base fame's cross bars. Now insert the Coin Holder. All the wiring should now be beneath everything.
10. Return to the car and connect the male and female leads. The reason I used snap on connecters here is so that at anytime in the future I can easily disconnect the lights by simply unplugging them. Test the LEDs again after you make the final connections. Now replace the entire Console back down in its original place and make sure all the wiring is underneath the console and none of the wiring is pinched. Since you used
20 gauge wiring like you should have all the wires should easily fit under there.
11. Turn on your car and turn on your Parking Lights. Your Cup Holders and Storage tray should now be glowing a glorious amber like the rest of your BMW dash. NOTE: You can dim the Cup Holder and Storage Tray LEDs with the Dimmer Switch found on your lower left Dash Board. This is good to have because if you use your parking lights in the daytime you can turn down the LED brightness and energy consumption. (Not that they consume lots of energy to begin with). You can also easily install a small rocker switch ($2 at Radio Shack) at the male/female connector leads if you want a separate switch for the Cup Holder and Storage Tray lights.
12. Daytime shots. You can still see the amber LEDs in daylight but it is not distracting at all.
13. Nighttime pics. The Amber really comes alive and matches the OEM Amber of the console. The first thing you think after seeing this effect is why didn't BMW think of this to begin with. The convenience alone is awesome, plus it is very visually impressive and not overwhelming. Also you can easily add a small switch to the console to turn them on/off if you eventually find having them on when you are not using them to be a bother.
Pictorial DIY Installation for BMW Cup Holder and Center Console LED Lights! 
