Genuine LiftMaster 050DCTBFLKMC lock-capable receiver logic board — the Security+ 2.0 DC board (yellow learn button) with the two extra terminals that drive the automatic garage door lock. It is the current replacement for the 050DCTWFLK, the 050DCTBLKMC / 050DCTBLK and the 041-0036, all of which LiftMaster has discontinued into this number. Fits the lock-capable DC belt and chain drive openers from LiftMaster and Chamberlain: 87802, 8550WLB, 8580WLB, WLED, 85502, B980 and the units of that family listed below.
Lock-capable means two things on the old board: a pair of screw terminals marked LOCK next to the sensor and wall-control terminals, and one of the part numbers above printed along the edge. If your board has no LOCK terminals and reads 050DCTWF, 050DCTB or 050DCTBFMC, order the 050DCTBFMC instead — it is the same board without the lock output.
Specifications
| Part number | 050DCTBFLKMC |
|---|---|
| Replaces | 050DCTWFLK, 050DCTBLKMC, 050DCTBLK, 041-0036, 50DCBL5LK |
| LiftMaster description | Logic Board, Bluetooth Enabled, Lock Capable |
| Learn button | Yellow — Security+ 2.0, tri-band 310 / 315 / 390 MHz |
| Connectivity | Wi-Fi and Bluetooth for myQ |
| Lock output | Two LOCK terminals for the 841LM / built-in automatic deadbolt |
| Power | DC belt and chain drive openers with battery backup |
| Condition | Genuine LiftMaster OEM, new |
Which openers use the 050DCTBFLKMC
| Opener | Parts page |
|---|---|
| LiftMaster 87802 heavy-duty chain, LED lighting, battery backup | 87802 parts |
| LiftMaster 8550WLB, 8550WLBMC, WLED (DC belt, battery backup, lock) | 8550 parts |
| LiftMaster 8580WLB Elite Series chain (built on the 8360 chassis) | 8360 parts |
| LiftMaster 85502 LED belt, battery backup | 85502 parts |
| LiftMaster 8160WLB (lock-capable 8160W) | 8160W parts |
| Chamberlain B980, B980C, B1381, B1381C (Chamberlain also lists the B1381 with the plain 050DCTBFMC — go by your old board) | B980 · B1381 |
Do not fit this to an opener that has no lock. It will run the door, but you will have paid for a lock output you cannot use, and the plain 050DCTBFMC is the listed part for those openers. AC lock-capable openers are different again: the 8587WL takes the 050ACTWFLKMC and the 85870 the 050ACTBLKMC.
Parts often replaced with it
841LM automatic garage door lock · 485LM backup battery · 041D8071-4 travel module · 041-0136 safety sensors · 893LM remote
Is the board actually the problem?
The logic board is the most over-ordered part on a garage door opener. Work down this list before you buy:
| Symptom | Check first |
|---|---|
| The lock cycles but the door will not move, or the lock never engages | The 841LM lock and its wiring to the LOCK terminals, and the lock setting in the myQ app, before the board |
| Opener completely dead — no light, no beep, nothing from the wall button | The outlet and breaker, then the line cord and the transformer. The board is last on this list, not first |
| Light comes on but the motor does nothing, or clicks once | On these DC units the motor and travel module, then the wiring between them and the board |
| Door will not close and the opener light flashes 10 times | The safety sensors — alignment, a cut wire or a sun-blinded eye. This is never the board |
| Remotes and keypad stopped working but the wall button works | Remote batteries, then re-program them to the learn button. Only if the learn button LED never lights is the receiver on the board suspect |
| Lost its Wi-Fi or myQ connection | The router, the phone app and the Wi-Fi signal in the garage — not the board. Re-run the myQ setup from the app before ordering anything |
| Runs a few inches and reverses, or stops short of the floor | Door balance and the travel and force settings first, then the travel module. The board only after those |
| Beeps every few seconds, or runs slowly on battery | The backup battery is a consumable — replace it before suspecting the board |
| Learn button LED never lights, opener runs one way only, or it failed the night of a storm | The board. Surge damage is the single most common reason one of these is replaced |
After fitting
The replacement board arrives blank. After fitting it you will need to set the travel limits and force, program every remote, keypad and vehicle HomeLink to the new learn button, and re-test the safety reversal on a 2x4 laid flat on the floor. Wi-Fi and myQ do not carry over — delete the old opener from the myQ app and add it again as a new device. Re-enable the automatic lock in the myQ app and check the deadbolt throws and retracts fully before the first close.
Put the opener on a surge protector when you fit the new board. Lightning and utility surges are the most common reason a garage door opener logic board is replaced, and a new board on the same unprotected outlet is at the same risk. A plug-in surge protector rated for motors is a small cost next to a second board.
Common questions
My board says 050DCTWFLK. Is this the right part?
Yes. The 050DCTWFLK was the Wi-Fi-only version; LiftMaster replaced it with this Bluetooth-enabled board and lists it under the same openers.
What about 050DCTBLKMC?
Discontinued. LiftMaster lists the 050DCTBFLKMC as the current number for it. The 050DCTBLKMC was fitted to the 87802 and 8580WLB.
Can I use the plain 050DCTBFMC and give up the lock?
It will run the door, but the 841LM will no longer work. If the opener has a lock, fit the lock-capable board.
Related
LiftMaster opener parts · Chamberlain opener parts · LiftMaster logic board cross reference · LiftMaster remotes
Not sure which board you need? Send a photo of the number printed on your existing board to parts@gatehousesupplies.com or call 866-965-5599. We would rather confirm it than have you fit the wrong board.
