Model # 1240R Official Chamberlain garage door opener

Here are the diagrams and repair parts for Official Chamberlain 1240R garage door opener, as well as links to manuals and error code tables, if available.

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Owner’s manual

Error Codes

Model diagram and schematic

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ALL PARTS

Showing 10 of 63 parts |

Motor unit assembly diagram

Garage door opener drive and worm gear kit (replaces 3002375, 65409)

Part #41A2817

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

#14

Motor unit assembly diagram

Garage door opener limit switch

Part #41D3452

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

Garage Door Opener Rpm Sensor Assembly 41C4398A

#15

Motor unit assembly diagram

Garage door opener rpm sensor assembly

Part #41C4398A

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

#NI02

All parts diagram

Owner's manual

Part #114A2217

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

Accessories diagram

10 foot (3m) complete rail

Part #1710LM

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

#12A

Motor unit assembly diagram

Cover (1246r, 1245r)

Part #41A3583-15

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

Accessories diagram

Outside quick release

Part #1702LM

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

#16

Accessories diagram

Motion detecting control panel

Part #98LM

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

#20

Motor unit assembly diagram

End panel w/all labels

Part #41A5014-3

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

Motor unit assembly diagram

Chain spreader w/screws (1256r, 1246r)

Part #41A4208

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.

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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…

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 is my garage door opener noisy?

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

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 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 does my garage door opener work intermittently?

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

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…

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.

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How to replace a chain-drive garage door opener gear and sprocket assembly

Learn how to replace the gear and sprocket assembly on your garage door opener if the drive motor runs but the door won'…

Repair difficulty

Time required

60 minutes or less

How to replace a garage door opener logic board

The logic board is the brains of the garage door opener. If the remote doesn't work or the door doesn't open and close p…

Repair difficulty

Time required

60 minutes or less

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.

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How to enjoy all the online benefits we offer on our Sears PartsDirect website

Learn about all the convenient features on our Sears PartsDirect website that make your parts purchases easier.…

Top questions about Sears and Sears PartsDirect

How to repair broken or damaged wires video

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

Model # 1240R Official Chamberlain garage door opener

Model diagram and schematic

SEARCH WITHIN THIS MODEL

Most common symptoms to help you fix your garage door openers

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

Why doesn't my garage door opener work?

Why is my garage door opener noisy?

What preventive maintenance does my garage door opener need?

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

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

Why does my garage door opener work intermittently?

Why does my garage door opener reverse on its own?

Most common repair guides to help fix your garage door openers

How to replace a chain-drive garage door opener gear and sprocket assembly

How to replace a garage door opener logic board

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

Effective articles & videos to help repair your garage door openers

How to enjoy all the online benefits we offer on our Sears PartsDirect website

Top questions about Sears and Sears PartsDirect

How to repair broken or damaged wires video

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