## Expansion Panel (J18)

Helios4 board was designed to either use the on-board LEDs or use a custom expansion panel (not-available). If you wish to use the header insure to switch to OFF the DIP switch SW2.

![Dipswitch LED](/img/led/dipswitch_led_off.png)

### Pinout Table

![J18 Pinout](/img/led/gpio_pinout_j18.png)

| Pin | LED number | Remarks |
|------------|----------|---------|
|  1 |  -   |  3.3V supply  |
|  2 |  -   |  Not connected |
|  3 | LED1 | Heartbeat LED  |
|  4 | LED2 | System Fault LED  |
|  5 | LED3 | SATA port 1 LED  |
|  6 | LED4 | SATA port 2 LED  |
|  7 | LED5 | SATA port 3 LED  |
|  8 | LED6 | SATA port 4 LED  |
|  9 | LED7 | USB activity LED  |
| 10 |  -   | GND |