Diagnostic Codes for Chamberlain & Liftmaster Garage Door Openers
Is the Light or Arrows on Your Garage Door Opener Flashing?
If the LED light next to the LEARN button or the UP and DOWN arrows are blinking or flashing, your garage door opener may be reporting a problem. The flashing pattern is a diagnostic code that can help identify the cause of an issue.
Diagnostic codes may appear as a repeating number of flashes, such as:
-
4 flashes, pause, 4 flashes
- 1 UP arrow flash followed by 5 DOWN arrow flashes
What Is Flashing on Your Garage Door Opener?
Different garage door opener models use different indicators to display diagnostic codes. Identify which lights are flashing, then select the link for your opener model to find the diagnostic code and recommended troubleshooting steps.
If the UP and DOWN arrows are flashing:
| Type of Garage Door Opener | Where to Find the Diagnostic Codes |
|---|---|
| Sec+2.0 myQ openers | Garage Door Opener Diagnostic Codes |
| 8500W, LJ8900W, LJ8950W | Diagnostic Codes: Wi-Fi Residential and Light-Duty Commercial Jackshaft Operators |
If the LED next to the LEARN button is flashing:
| Type of Garage Door Opener | Where to Find the Diagnostic Codes |
|---|---|
| AC powered garage door openers | What Does the Flashing LED Next to the Learn Button Mean |
| 3800/3900/8500/RJO20/RJO20C | Diagnostic codes for Residential Jackshaft Opener (RJO) |
| 2500B, 2500D, 3500 and 3850 -DC Unit- | 2500B, 2500D, 3500 and 3850 - Diagnostic Code Chart |
| 2500 | Liftmaster® Model 2500 - Diagnostic Code Chart |
Need Help Identifying Your Model?
The model number is printed on a label attached to the garage door opener motor unit. Using the model number helps ensure you use the correct diagnostic code chart.
-
Locate the label on the side or back of the garage door opener motor unit.
- Find the model number.
- Use the diagnostic chart that matches your opener.
See: How to Find a Model Number on a Garage Door Opener
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