Why won't my garage door close?

Common reasons include: misaligned safety sensors, obstructions in the door path, broken springs, stripped gears in the opener, or issues with the close limit settings. Check the safety sensors first - they should both have steady lights.

Should I repair or replace my garage door?

Consider replacing if: the door is over 15-20 years old, has significant rust or structural damage, panels are severely damaged, or you want to upgrade to an insulated door. Many issues like springs, cables, sensors, and openers are cost-effective to repair.

What do the blinking lights on my garage door opener mean?

Blinking lights indicate error codes. For LiftMaster/Chamberlain: 1 blink = sensor wire issue, 2 blinks = sensor wire short, 3 blinks = door control wire issue, 4 blinks = sensor misalignment, 5 blinks = motor issue. Use our error code lookup tool for specific diagnosis.

How do I calculate what torsion spring I need?

To calculate the correct torsion spring, you need: door height, door width, door weight, track type, and number of springs. The formula involves IPPT (Inch-Pounds Per Turn) = d^4 × E / (10.8 × D × Na). Use our spring calculator for accurate results.

Can I replace a garage door spring myself?

Torsion spring replacement is dangerous and recommended only for trained professionals due to the extreme tension (over 200 lbs of force). Extension springs are safer for DIY but still require proper safety precautions and tools.

Garage Door Opener Error Codes

Identify what your opener's blinking lights mean and how to fix common problems.

LiftMaster Error Codes

Professional-grade openers by Chamberlain Group

Full Brand Guide

1 blink

Moderate

1 blink

ModerateDIY Possible

Sensor wire open or disconnected

Solution

Check that both sensor wires are securely connected to the terminals on the opener. Inspect wires for breaks.

DIY Possible

2 blinks

Moderate

2 blinks

ModerateDIY Possible

Sensor wire shorted

Solution

Look for bare wires touching each other or metal. Check for pinched or damaged insulation. Replace wire if damaged.

DIY Possible

3 blinks

Moderate

3 blinks

ModerateDIY Possible

Door control wire shorted

Solution

Inspect the wires running from the wall button to the opener. Look for damage or bare spots touching.

DIY Possible

4 blinks

Easy Fix

4 blinks

Easy FixDIY Possible

Safety sensors misaligned

Solution

Adjust both sensors so they face each other directly. Both sensor lights should be solid (not blinking). Clean sensor lenses.

DIY Possible

5 blinks

Moderate

5 blinks

Moderate

Motor thermal overload

Solution

Wait 15-30 minutes for the motor to cool. Check if door is binding or too heavy. Test door balance manually.

6 blinks

Easy Fix

6 blinks

Easy FixDIY Possible

Sensor wires reversed

Solution

Swap the white and white/black sensor wires at the opener terminal. Re-test operation.

DIY Possible

1-5 pattern

Professional

1-5 pattern

Professional

RPM sensor failure

Solution

Internal motor sensor malfunction. Professional service typically required. May need motor replacement.

Up arrow flashing

Easy Fix

Up arrow flashing

Easy FixDIY Possible

Travel limits not set

Solution

Program the open and close travel limits using the limit adjustment buttons on the opener.

DIY Possible

Light stays on

Informational

Light stays on

InformationalDIY Possible

Light feature active

Solution

This is normal. Light turns off after 4.5 minutes. Press light button to turn off immediately.

DIY Possible

No lights/response

Easy Fix

No lights/response

Easy FixDIY Possible

Power issue

Solution

Check if opener is plugged in. Check circuit breaker. Test outlet with another device.

DIY Possible

How to Read Error Codes

Counting Blinks

1Press the wall button to try to operate the door
2Watch the LED light on the opener motor unit
3Count the number of blinks before the pause
4The pattern will repeat - count again to confirm

Common Patterns

1-4 blinksSensor issues

5 blinksMotor/thermal issue

6+ blinksInternal/board issue

Solid lightUsually normal

No lightPower issue

Opener Brand Guides

LiftMaster Chamberlain Genie Craftsman Linear / Nortek Marantec