Problem with "Blinkers" for bike trailer?

Ok thanks heaps!
So when I get home from school I should try my original code (but add a bit to enable internal pull-up resistors) and hook up the circuit like this:
Also I understand about the pull-up resistors now :slight_smile: .

Resistors (R1 and R2) are 15 ohms.

LED1 LED2
| |--------------------| |
| \ |
R1 \ R2
| \ |
| \ |
pin 13 GND Pin 12

| |
| Arduino Board |
| |
| Internal 20k Pull-up |
| Resistors |
=======================
Pin 10 Pin 9 Pin 10 GND
| | \
| | \
| | \
Switch 1 Switch 2 Switch 3
|-------------|-------------|-------|