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ErrBase

LiftMaster 4-6 Error Code: Travel Limit Not Set or Sensor Fault

Quick Answer

LiftMaster 4-6 means the opener finished its travel cycle but did not receive confirmation from the sensor that the door actually reached the end position. This happens most often when travel limits need to be reprogrammed, or when the safety sensors are out of alignment.

LiftMaster 4-6 means the opener finished its travel cycle but did not receive confirmation from the sensor that the door actually reached the end position. This happens most often when travel limits need to be reprogrammed, or when the safety sensors are out of alignment. Reprogram travel limits using the UP/DOWN limit adjustment buttons on the motor unit, then verify the safety sensor LED is solid green on the receiver.

LiftmasterGaragedoorSeverity: highDifficulty: intermediate80% DIY Success
Time to Fix
20–60 min
Difficulty
intermediate
Parts Cost
$10 – $45
Tools Needed
Ladder, Flathead screwdriver

What Does the 4-6 Code Mean?

The 4-6 code fires when the opener motor completes its run but the travel sensor or safety sensor does not confirm the door reached open or closed position. Start by reprogramming travel limits.

Most Likely Causes

Based on aggregated repair data, here is the probability breakdown for this error code:

Travel limits need reprogramming40%
Safety sensor out of alignment24%
Logic board fault22%
Sensor wire damaged or broken14%

Symptoms You May Notice

  • Door stops partway and reverses
  • Door opens fully but opener blinks 4-6 when trying to close
  • Door closes but reopens immediately
  • LED on motor unit blinks 4 times, pauses, then 6 times

Can you reset a Liftmaster garagedoor to clear the 4-6 code?

To clear the 4-6 code: unplug the opener for 60 seconds and plug back in. Then reprogram travel limits by holding the UP limit button with the door open, and the DOWN limit button with the door closed. The code will clear once the opener accepts the new travel positions.

Tools Required for Diagnosis

LadderFlathead screwdriverTape measure

Diagnostic Checklist

Follow these steps in order. We start with the easiest external fixes before opening up the machine.

1

Inspect both safety sensors at the bottom of the door tracks

Inspect both safety sensors at the bottom of the door tracks. The sending sensor (yellow LED) should be solid. The receiving sensor (green LED) should also be solid, not blinking.

2

Locate the UP and DOWN limit adjustment buttons or knobs on the

3

Reprogram travel limits

4

Inspect the sensor wires running from the motor unit down to

5

Run a full open and close cycle and watch for the LED blink pattern

Replacement Parts

If your diagnostic testing proves the component has failed, you will need a replacement. We recommend OEM parts over aftermarket for water-handling components.

Part Name
Safety Sensor Kit (pair)41A5034 · $25–$45
Sensor Wire (white, 2-conductor)41A5034-1 · $10–$20

Repair vs. Replace Calculator

Appliance Age (Years)7 Yrs
Labor Approach
Our Verdict
REPAIR
Estimated Cost: $28 (Parts) vs $400 (New Machine)

Frequently Asked Questions

What does LiftMaster 4-6 mean exactly?
4-6 means the opener motor finished its travel cycle but did not receive a confirmation signal that the door actually reached its intended end position (open or closed). The two most common causes are travel limits that need reprogramming and safety sensors that are not aligned.
My door closes but then immediately reopens showing 4-6. What is wrong?
This usually means the DOWN travel limit is set too far, causing the door to hit the floor and then trigger a safety reversal. Reduce the DOWN limit by pressing and holding the DOWN arrow button while the door is fully closed to set a new lower limit.
Will a power outage cause a 4-6 error?
Yes. On some older LiftMaster models, a power outage can erase the stored travel limit settings, causing the 4-6 code to appear the next time the door is operated. Reprogramming the limits fixes it immediately.
How do I know if the problem is the travel limits versus the sensors?
Check the receiver sensor LED first. If it is solid green, the sensors are fine and the problem is the travel limits. If the receiver LED is blinking or off, fix the sensor alignment before touching the travel limits.
Can I fix a LiftMaster 4-6 code myself or do I need a technician?
Most 4-6 errors are DIY-fixable. Reprogramming travel limits and realigning sensors require no special tools and take 15 to 30 minutes. If the wire is damaged or the logic board has failed, those repairs are more involved but still achievable for a confident DIYer.

Related Liftmaster Garagedoor Error Codes

Code: HUBLiftMaster Garage Door Opener Error Codes: Complete LED Blink Code GuideCode: 4-2LiftMaster 4-2 Error Code: Safety Sensor Eye Misaligned or BlockedCode: 4-4LiftMaster 4-4 Error Code: Safety Sensor Beam Blocked or DirtyCode: RESETLiftMaster Garage Door Opener Error Codes: Complete LED Blink Code Guide

Same Fix on Other Brands

Chamberlain 4-6:

Models Known to Experience 4-6 Errors

This repair applies to most Liftmaster garagedoors with this error code. Common model numbers include:

8500W, 8550WLB, 87504-267, 84505R, 83504

Last verified for technical accuracy on March 14, 2026