Troubleshooting
Nothing lights up at all
6 checks, sorted by how often they are the cause. For all WLED controllers with ESP32.
Check in this order: the most common and simplest cause comes first. Usually the cause is found after two or three steps.
Power at the strip?
Measure between + and GND at the start of the strip with a multimeter. It must match the strip voltage (5, 12 or 24 V).
Right end connected?
The arrows on the strip must point away from the controller. The controller goes on DIN (data in). At the wrong end everything stays dark.
Is the output switched on in WLED?
In the UI: power on, brightness above 0, colour not black. Sounds trivial, but often happens after a reset.
Data pin and LED count correct?
Config → LED Preferences: GPIO per controller datasheet, length above 0, matching LED type (usually WS281x).
Relay pin set?
Controllers with relays (e.g. 4336-616, 4336-116-RF) only power the output when the relay GPIO is set. 4336-116-RF: IO21 and IO19.
First pixel faulty?
A faulty first chip blocks all following ones. Cut off the first section as a test and reconnect.
Further help
LED-Emotion: WLED basics (German) ↗
Power supply, consumption, GND, level shifter and installation explained in detail.
LED-Emotion: “LED Preferences” menu (German) ↗
Every setting in WLED’s LED menu step by step.
Set planner →
Calculate PSU, feed points, current per pixel and matching controllers for your strip.
Other problems
- Flickering, glitter or random colours
- Colours are wrong (red is green …)
- Reddish, yellowish or dimmer towards the end
- Controller can't be reached on the network
- Too dim even at full brightness
- Glows or flashes when switched off
- Controller keeps rebooting
- Doesn't react to music
- Remote doesn't respond
- Lights up only up to a certain point
- Second output or zone stays dark
- Effects stutter or run slowly
- Strip, PSU or controller gets hot
- White looks bluish, pink or uneven
- Settings or presets are gone
- Update failed or controller won’t start
- Home Assistant can’t find WLED
- Schedule switches at the wrong time
- Several controllers aren’t in sync