Resource guide
Device Light Troubleshooting Checklist
A simple checklist for troubleshooting blinking, flashing, solid, red, orange, green, blue, white, and warning lights on everyday devices.
Use this quick checklist
Before you reset, replace, or ignore a device, run through the basics. This checklist works for many routers, printers, chargers, smart home devices, TVs, remotes, laptops, and appliances.
Step-by-step checklist
- Identify the device type and brand.
- Find the exact model number.
- Write down the light color.
- Write down the blink pattern.
- Check the label beside the light.
- Check the app, screen, or error message.
- Check power, batteries, cables, and removable parts.
- Wait if the device is booting, updating, charging, or syncing.
- Restart only when it is safe.
- Check the official manual before factory resetting.
Stop if safety is involved
If the light involves smoke, carbon monoxide, brakes, oil pressure, overheating, batteries, chargers, medical devices, gas, fire, sparks, or electrical smell, stop normal troubleshooting and follow official safety guidance.
Related next steps
After using this guide, try the Find a Light tool, browse by device type, or check the safety-critical lights hub if the warning may involve risk.