Residential Jackshaft Opener | Troubleshooting Travel Limit Loss

If you find yourself reprogramming the travel limits more than once on your wall mount opener (Residential Jackshaft Operator or RJO), there may be an issue with one of the following parts.

Step 1: Check the Collar

The collar connects the opener to the garage door’s torsion bar. If it isn’t tight, the opener can lose track of the door’s movement.

1. Inspect the collar installation.
   • See: Jackshaft Opener: Installation requirements for the Jackshaft Openers 
2. Mark alignment.
   • Draw a straight line across the drive shaft, collar, and torsion bar.
3. Run two full open-and-close cycles.
   • If the lines still match, continue to Step 2.
   • If the lines don’t match, tighten the collar. 
4. Secure the collar.
   • Tighten all four screws until flush and secure.
   • If your collar has two small 1/8" set screws, tighten those as w
5. Replace if needed.
   • If the collar still slips, replace it with service kit 041D8615. 

For details, see VIDEO-How to Tighten the Collar on a LiftMaster Garage Door Opener, Model 8500

Step 2: Check the Drive Shaft Gear

The drive shaft gear turns the gears on the travel module. If the collar is installed correctly, then the drive shaft gear may be slipping on the shaft.

1. Remove the opener cover.
2. Locate the drive shaft gear.
   • It’s on the top left side of the unit.
   • This is the gear that turns the gears on the travel module.
3. Disconnect the door.
   • Pull the red emergency release.
4. Manually move the door.
   • Have someone slowly open or close the door by hand.
5. Tighten the gear screws.
   Find the two 1/16" set screws (180° apart) and tighten both.

Step 3: Check the Travel Module 

The travel module sends the door’s position to the opener’s logic board.

1. Inspect wiring.
   • Make sure the wires between the travel module and logic board are snug and secure.
2. Replace if needed.
   • If wiring is fine but limits are still lost, replace the travel module.
   • If the issue continues, replace the logic board.

Next Steps

• Reprogram your travel limits.
• If the opener continues to lose limits after replacing parts, contact a professional LiftMaster dealer for service.