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Garage Door Opener

Model # 3850 Official Chamberlain garage door opener

Here are the diagrams and repair parts for Official Chamberlain 3850 garage door opener, as well as links to manuals and error code tables, if available.

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Owner’s manual

Model diagram and schematic

SEARCH WITHIN THIS MODEL

ALL PARTS

Showing 10 of 49 parts |

Master Link 4A1008

Master link

Part #4A1008

The manufacturer no longer makes this part, and there's no substitute part

Garage Door Opener Light Socket 4A1344

Garage door opener light socket

Part #4A1344

The manufacturer no longer makes this part, and there's no substitute part

Garage Door Opener Safety Sensor Kit 41A5034

Garage door opener safety sensor kit

Part #41A5034

The manufacturer no longer makes this part, and there's no substitute part

Ownerâ??s Manual - Spanish 114A3406SP

Ownerâ??s manual - spanish

Part #114A3406SP

The manufacturer no longer makes this part, and there's no substitute part

Laser Park Assist 975LM

Laser park assist

Part #975LM

The manufacturer no longer makes this part, and there's no substitute part

Push Bar For Door Control 101D173

Push bar for door control

Part #101D173

The manufacturer no longer makes this part, and there's no substitute part

Cover 41D504-4

Cover

Part #41D504-4

The manufacturer no longer makes this part, and there's no substitute part

Remote Light Control 395LM

Remote light control

Part #395LM

The manufacturer no longer makes this part, and there's no substitute part

3v2450 Lithium Battery: Proximity Switch 10A33

3v2450 lithium battery: proximity switch

Part #10A33

The manufacturer no longer makes this part, and there's no substitute part

Ownerâ??s Manual 114A3406

Ownerâ??s manual

Part #114A3406

The manufacturer no longer makes this part, and there's no substitute part

Most common symptoms to help you fix your garage door openers

Choose a symptom to see related garage door opener repairs.

Why does my garage door opener open and close by itself?

Main causes: neighbor's remote programmed at the same time as yours, faulty wall control wiring, bad wall control unit…

What preventive maintenance does my garage door opener need?

Things to do: check garage door travel, tighten brackets and fasteners, test safety sensors, check travel limits and for…

Why does my garage door opener reverse on its own?

Main causes: safety sensor beams blocked, safety sensors not aligned, downforce setting needs adjustment, damaged garage…

Why won't my garage door opener fully open or close the garage door?

Main causes: garage door opener misaligned, travel limits need adjustment, bad travel limit switches, faulty logic contr…

Why won't my garage door opener open the garage door?

Main causes: garage door locked, damaged garage door tracks, up-force setting needs adjustment, RPM sensor failure, bad …

Why is my garage door opener noisy?

Main causes: loose fasteners, broken brackets, need preventive maintenance, worn drive gears, loose or worn belt, loose …

Why doesn't my garage door opener work?

Main causes: faulty logic control board, bad RPM sensor, broken gears in the drive system, bad drive motor…

Why does my garage door opener work intermittently?

Main causes: radio interference, weak remote batteries, sunlight interference with safety sensor beams, safety sensors n…

Most common repair guides to help fix your garage door openers

These step-by-step repair guides will help you safely fix what’s broken on your garage door opener.

How to replace a chain-drive garage door opener motor

How to replace a chain-drive garage door opener motor

Get your garage door moving again by replacing a defective motor in your garage door opener.…

Repair difficulty

Time required

60 minutes or less

How to replace a belt-drive garage door opener motor

How to replace a belt-drive garage door opener motor

The garage door won't move if the motor is defective. Here’s how to fix it.…

Repair difficulty

Time required

60 minutes or less

How to replace a garage door opener drive chain and cable assembly

How to replace a garage door opener drive chain and cable assembly

If your garage door won’t move, the chain and cable assembly on your garage door opener could be broken. Follow these st…

Repair difficulty

Time required

60 minutes or less

Effective articles & videos to help repair your garage door openers

Use the advice and tips in these articles and videos to get the most out of your garage door opener.

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…

How to repair broken or damaged wires video

How to repair broken or damaged wires video

Learn how to repair broken, frayed or damaged wires in your appliances.…

How to open a garage door with an opener manually

How to open a garage door with an opener manually

Learn how to open a garage door manually if power to your garage door opener fails.…

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