Toyota Corolla DIY

This DIY will help you put LEDs into your cupholders. I have each cupholder switched so you can control which one to turn on. I tapped the unused cigarette lighter for power. They only turn on when the parking lights or headlights are on.

Materials:
2 LED bulbs – I used 10mm 135K mcd

2 Resistors – 470 ohms
18 to 22 Gauge Wire
2 Rocker Switches – I used switches rated 10A at 125VAC (You can use any rocker switch you like)

Tap-In Squeeze Connectors

Heat Shrink Tubing (optional)

Electrical Tape
Sandpaper

Tools:
Wire Stripper
Soldering Iron
Solder
Hot Glue Gun
Philips and Flathead Screwdrivers
10mm Socket Wrench
Dremel or Drill
Needlenose Pliers

First prep your LEDs. Grind or cut down your LEDs to a nice small size (about half its size). Then use sandpaper to sand down the top. This will diffuse the light rather than having a spotlight. Make sure the entire top is sanded. Light will shine through any unsanded areas so do a good job here.

Solder your resistor to the anode (longer leg).

To figure out which resistor to use, use the formula:
R = (V1 – V2) / I

where:
V1 = power supply voltage
V2 = LED voltage
I = LED current

Example:
R = (12V – 3V) / .02A
R = 450 ohms

If you don’t have the exact ohm resistor, you can wire up multiple resistors. When doing this, you should use resistors that add up to a higher resistance than the required resistance. Example: if 500 ohms is required and all you have are 200 ohm resistors, use 3 of them.

Test your LEDs by using an AA battery.

Now in the car, pull your parking brake and put the shifter in L (AT only). Disconnect the negative terminal of your battery. Remove the shifter trim and unplug the cigarette lighter.

Remove the 4 screws and 2 bolts in the armrest. Remove the parking brake hole cover.

Unplug the wire (under center console) that connects to the cigarette lighter in the armrest.

Now lift and remove the console box (armrest).

Take it out of the car and onto the floor (lay down a blanket to prevent scratches). Flip it over and find the center of each cupholder and mark it. Now drill your holes! Remember to use a drill bit that is about the same size as your LED bulb.

Get your parking brake hole cover. Mark the holes for the switches. Drill the holes and place your switches. Go back into the car and find the unused cigarette lighter wires. The green wire is positive and the white/gray wire is your ground. Use a tap-in connector and tap the green wire along with your positive wire. Run enough wire to your switch location and cut it. Strip and tin your wire.

Now tap the positive wire that’s going to the first switch. This will go to the second switch. Again strip and tin this wire.

Back to the LED bulbs. Solder on a positive wire to each bulb. This will go to the switch. About 6-9 inches in length. You can always trim it later. Measure the required length just in case. Now solder on the ground wires. The ground on the front bulb will be longer than the other. It should be a little longer than the positive wire that’s going to the front switch. For the rear bulb, the ground wire will be short because you will be tapping into the front bulb’s ground. Once those are soldered, electrical tape and heat shrink the LED legs.

With your needlenose pliers, bend the LEDs 90 degrees.

Now hot glue the LED bulbs to the cupholders. I’m using hot glue because if you use an adhesive and need to change the bulb in the future, it’ll be tough to pop out. Make sure its nice and secure and angled STRAIGHT UP!!! Again, you can use a battery to test that its shining up. Let it dry and flip it over and seal the rim of the bulbs. You do not want water getting in and causing a short!

Tap the ground wire of the back bulb to the ground wire of the front bulb.

Go back into the car and solder the positive wires to the switches then put the armrest console back OR put the console armrest back into place, slightly open so you have enough room to mess with the wires and solder the wires to the switches. Solder the positive wires from the LED to the switches.

Then tap the ground wire from the front bulb to the white/gray wire of the cigarette lighter.

Double check your connections and wrap any exposed wires with electrical tape.

Everything should be wired according to the bootleg wire diagram.

Once you’re sure everything is right, reconnect your battery. Turn on your parking lights and switch on the cupholder lights. They should light up! If not, check your connections again.

Now you can snap the parking brake hole cover back into place. Put everything back into place and screw it back. Now go impress your friends, especially the one’s with scions who paid the stealership $275 to install the Interior Light Illumination Kit. This whole DIY costs about $10 to do hahhaha