How to Use Brick Power Functions: Motor to Remote Control
Bottom line first: power functions are not difficult. There are only three moves — seat a motor in the chassis, connect the battery box, pair the remote — and a beginner can have a MOC running in about 30 minutes. A basic kit (2 M motors + battery box + remote) costs roughly 80-150 RMB, considerably less than an official set.
Most builders finish a static MOC and immediately want to make it move. Power functions are simply the system that puts motors, a battery box, a receiver and a remote control inside a brick-built structure. This guide walks the whole workflow, from identifying the parts to remote-control upgrades, and every step can be followed as written.
Step 1: Meet the Four Core Parts
Sort out the components before you touch a brick. A complete power functions set contains:
- M motor — around 380 rpm, low torque, best suited to driving wheels.
- L motor — around 220 rpm, high torque, best suited to lifting and steering.
- Battery box — usually takes 6 AA batteries and outputs 9V.
- Receiver and remote — typically supports 2-4 channels.
When buying, look for a bundle that packs motor + battery box + remote together. That works out around 30% cheaper than buying the pieces separately.
Step 2: Mount the Motor and Drivetrain
The key principle is "position first, fix second." Seat the motor in the space you left in the chassis, then connect the motor shaft to the wheel axle with a cross axle and gears. Three things to watch:
- The motor output shaft must sit at the same height as the drive axle, or the gears will bind and lock up.
- Fix the motor with at least two mounting points so it cannot shift while running.
- Put the steering motor as close to the middle of the chassis as you can, so the left and right weight stays balanced.
Step 3: Wiring and Power-On Test
The wiring order is fixed: battery box → receiver → motor. Plug the battery box cable into the power port on the receiver, then connect the two motors to channel 1 and channel 2 respectively. After loading the batteries, test before fitting the bodywork: move the remote stick and check that the motors spin freely, then install them in the chassis. If a motor will not turn, nine times out of ten the cable order is reversed or the battery voltage is too low — try a fresh pair of batteries first.
Step 4: Remote Control Upgrades and Expansion
Once the basic build runs, you can step up the play: add a linkage to the steering motor for remote-controlled steering, pair an L motor with a worm gear to build a lifting arm, or fit a light module (around 20-40 RMB) for a better look at night. Before modifying anything, download a MOC plan with power functions mounting points from brickplan.cn — the plans mark the motor bay dimensions, so you will not discover halfway through that there is not enough room.
FAQ
Q: What is the difference between brick power functions and an ordinary motor?
A: Power functions are a complete system designed for bricks, including motor, battery box, receiver and remote. The connectors are fully compatible with brick parts and work plug-and-play. An ordinary motor has to be soldered and modified by hand, and the connectors do not match — not recommended for beginners.
Q: How do I choose between an M motor and an L motor?
A: The M motor has high speed and low torque, so it suits driving wheels for speed. The L motor has low speed and high torque, so it suits steering, lifting and other heavy-load structures. For a single vehicle, "M motor for drive + L motor for steering" gives each motor the job it does best and is the most reliable setup.
Q: The motor is jammed and will not turn after installation. What now?
A: Cut the power and check whether the gears are meshed too tightly — you should be able to turn them gently by hand. Then confirm the motor shaft is aligned in height with the drive axle, and finally test with new batteries. If it still will not turn, the motor may be burned out; contact the seller for a replacement if it is still under warranty.
Q: How much does a power functions set cost, and is it worth buying?
A: A basic kit is 80-150 RMB and includes two motors and a remote. An advanced four-motor kit runs about 200-300 RMB. Official power functions sets often start at 400 RMB and up, so third-party compatible parts offer much better value and are entirely sufficient to get started.
Q: Can I control brick power functions with my phone?
A: Yes. Some Bluetooth battery boxes support phone app control for 30-50 RMB more than the remote version. They also let you program speed and set up action sequences, which suits more advanced builders who want smart control.