Liftmaster LA400 Swing Gate Parts
LiftMaster LA400 Replacement Parts
Genuine LiftMaster replacement parts for the LA400 linear actuator swing gate operator — the 24 VDC battery-backed arm operator that drives the gate with a sealed electric ram. Use the diagram above to find the key number for the part you need, then click any part number in the tables below to go straight to that product.
Is your control board green or is it in a plastic box? The original LA400 uses the K001A6039 board in a metal box — that is this page. The later LA400U and LA400UL use a UL325 main board (K1D8388-1CC) in a plastic control box and share almost nothing in the control box with this model. The arm parts are the same on both.
Two assemblies, two tables. The control box parts (Refs 1–8) are in the wall-mounted box; the operator arm parts (K1–K4) are on the actuator itself.
Careful with the bracket kits. K77-19130 is the standard hardware kit; K77-19130-1 is the two-post variant. One digit apart, not interchangeable.
The fuse is not a LiftMaster part. It is a standard 20 amp automotive blade fuse. The K74-30941 kit is there if you would rather buy it with the correct spares.
Common LA400 Repairs
| Symptom | Usual cause | Parts to check |
|---|---|---|
| Gate runs on mains but dies in a power cut | Battery pack at end of life | K74-30762 battery pack, K74-30754 battery harness |
| Operator completely dead | Blown fuse or transformer | K74-30941 fuse kit, K74-30763 transformer |
| No response to remotes, wired controls work | Receiver module or antenna | K001A5747 receiver module, K74-19499 antenna |
| Gate will not reset after an obstruction | Reset switch | K23-19380 reset switch |
| Arm hums but the gate does not move | Motor or drive nut worn | 041ASWG-0438SA motor, 041ASWG-0442SA release lever |
| Cannot release the gate by hand | Release lever or key | 041ASWG-0442SA lever, 041ASWG-0119 release keys |
| Intermittent operation, arm cuts out | Cable between box and arm | 041ASWG-0489 24V cable with connector |
| Erratic behaviour after a board swap | Firmware chip version | K-127A0071E chip V1.6 |
Standard Control Box
| Ref | Part # | Description |
|---|---|---|
| 1 | K001A6039 | Control Board, LA400 |
| 2 | K75-15480 | Control Box and Cover, LA400 |
| 3 | K75-30764 | Control Board Mounting Bracket |
| 4 | K23-19380 | Reset Switch |
| 5 | K74-19499 | Antenna |
| 6 | K74-30762 | Battery Pack, 12V, 7A |
| 7 | K74-30763 | Transformer |
| 8 | K76-19446 | Alarm |
| — | K74-30941 | Fuse Kit |
| — | K001A5747-2 | Receiver Module, 315MHz |
| — | 041ASWG-0119 | Release Key, Qty 2 |
| — | K001A5747 | Receiver Module, 315MHz |
| — | K-127A0071E | Chip, V1.6, LA400 |
| — | K74-30754 | Battery Harness |
| — | K77-19130-1 | Two Post Bracket Kit, LA400 / LA412 |
Gate Operator Arm
| Ref | Part # | Description |
|---|---|---|
| K1 | 041ASWG-0442SA | Release Lever |
| K2 | 041ASWG-0438SA | Motor, 24V |
| K3 | 041ASWG-0014SA | Rear Connector |
| K4 | 041ASWG-0489 | Cable, 24V, 3m, with Connector |
| — | K77-19130 | Hardware Kit, LA400 / LA412 |