How to Read Your Raspberry Pi's LEDs and Troubleshoot Boot Issues

The position LEDs connected a Raspberry Pi machine bespeak what's going connected and tin thief you troubleshoot powerfulness and footwear issues.

A Raspberry Pi isn’t conscionable a credit-card-sized gateway to exploring nan immense world of computing and electronics. The single-board machine is besides tin of communicating its existent operating authorities and whether location are immoderate footwear issues to nan user.

Want to cognize really your Raspberry Pi is feeling? In astir cases, conscionable taking a look astatine nan LEDs connected nan committee should beryllium enough. We will return a adjacent look astatine these position LEDs and explicate really you tin find what they indicate.

What Are nan Different Status LEDs On nan Raspberry Pi?

The number and statement of LEDs disagree crossed Raspberry Pi models. There are 4 LEDs successful full connected astir Raspberry Pi boards: 2 adjacent to nan powerfulness larboard (they whitethorn beryllium person to nan GPiO header connected immoderate models) and 2 connected nan Ethernet port. The Raspberry Pi Zero has 1 LED adjacent to nan powerfulness larboard and nan very first Raspberry Pi, nan Model B (now discontinued), had 5 LEDs connected nan board.

On a Raspberry Pi 4B, you will find 2 position LEDs, a reddish and a green, on nan separator starring disconnected from nan powerfulness larboard to nan MIPI DSI port. The reddish LED is branded PWR while nan greenish is branded ACT.

There are besides 2 LEDs connected nan Ethernet port, greenish (LNK) and yellowish (100/10M), which pass accusation astir nan Ethernet connection. The greenish LED indicates activity complete nan Ethernet web and flashes during information transfers, while nan yellowish LED indicates a 100 Mbit Ethernet nexus connected older models aliases a 1000 Mbit nexus connected Raspberry Pi 3B+ and 4. The yellowish LED remains disconnected for lower-speed connections.

These LEDs stay progressive during emblematic operation, but it is imaginable to move them disconnected to prevention powerfulness successful your low-power aliases portable Raspberry Pi projects.

Below, we are going to beryllium taking a person look astatine nan position LEDs straight connected nan board. The accusation they pass is of overmuch superior importance, compared to nan Ethernet LEDs.

What Does nan Red Status LED Indicate?

The reddish position LED (PWR) is arsenic its sanction suggests responsible for indicating whether nan Raspberry Pi receives capable powerfulness to beryllium turned on. On older models, it would move connected instantly aft a powerfulness proviso was connected to nan Pi. But successful later models, starting from nan B+, nan reddish LED is besides tin of indicating if a powerfulness proviso is not providing capable voltage required by nan Raspberry Pi. In this case, it would either flash aliases move off.

If nan powerfulness LED is not functioning arsenic expected, it is simply a bully motion that you should link a amended powerfulness proviso to nan Raspberry Pi. You tin besides study much astir really to reduce powerfulness depletion successful your Raspberry Pi projects.

What Does nan Green Status LED Indicate?

The greenish position LED is designated arsenic ACT (short for "activity"), and it is simply a spot trickier to decipher than nan powerfulness LED. This LED is nan only 1 coming connected nan Raspberry Pi Zero models. Generally, it indicates SD paper activity.

This LED remains coagulated and consistently connected during regular operation. It flashes erstwhile applications are running—that is, erstwhile publication and constitute operations are ongoing—and should flash often successful an irregular shape erstwhile nan Raspberry Pi is booting. However, it whitethorn not move connected if location are immoderate issues pinch your installation aliases nan SD paper itself.

The ACT LED besides flashes successful circumstantial patterns to bespeak problems pinch booting. This useful otherwise connected models earlier than nan Raspberry Pi 4B owed to changes successful really nan bootloader useful connected nan 4B.

Raspberry Pi 3B+, Pi Zero and Earlier Models

The array beneath describes what different greenish LED flashes mean connected a Raspberry Pi 3B+, Zero, and earlier models (bar nan original Pi Model B).

Raspberry Pi 4, Pi 400 and Compute Module 4

The Raspberry Pi 4, 400, and nan Compute Module 4 each footwear from an EEPROM connected nan board, dissimilar older models which usage nan bootcode.bin record successful nan footwear filesystem connected nan SD card.

In these models, nan LED patterns are a spot much analyzable which intends that they tin relay much accusation astir nan footwear sequence. The ACT LED will blink for a definite number of agelong flashes (0 aliases more), followed by a series of short flashes, to bespeak nan nonstop status. Usually, nan shape will repetition itself aft a two-second gap.

Any 1 of nan statuses supra indicates a footwear problem and whitethorn require that you either alteration nan microSD paper aliases upgrade/update nan bootloader. Newer versions of nan Raspberry Pi 4 bootloader (starting from type 2020-04-16) will show a diagnostic connection astatine footwear clip connected a connected HDMI display.

Raspberry Pi 1 Model B

The original Raspberry Pi Model B from 2012 utilized firmware that depended connected nan loader.bin record and truthful nan flashes connected nan LED meant somewhat different things.

It Is Easy to Troubleshoot Boot Issues connected a Raspberry Pi

The position LEDs connected nan Raspberry Pi are beautiful insignificant during normal operation, but they quickly go important erstwhile you request to diagnose footwear issues. While location are galore reasons why a Raspberry Pi won’t footwear up, checking nan position LEDs and counting nan flashes connected nan greenish ACT LED is simply a awesome measurement to statesman uncovering retired why.