Straight answers to what actually goes wrong on electric bikes, scooters and e-mopeds — written by the people who wrote the certification course, and free to read. Every answer is the real first check, not a teaser.
Measure at the source, then follow the chain: battery, connection, controller, motor, wheel. The first place the answer is "no" is where your problem lives. Check the cheap, likely causes before the expensive, unlikely ones — a controller ordered for a sticky brake lever is a bad afternoon.
Check the brake levers first. Most electric bikes have a cutoff sensor in each lever that kills motor power the moment you brake, and a lever that does not return fully — a sticky pivot, a bent lever, a binding cable — leaves that sensor permanently triggered. The controller believes you are braking forever, so the motor never runs. It is the most commonly missed diagnosis in this trade, it costs nothing to rule out, and on many systems it also throws an E02 code.
That is almost always a connector, not a component. On round Julet or Higo connectors the locking collar has to be threaded fully down; half-engaged, the pins still touch on the stand but separate for a few milliseconds over a pothole. Go around the whole vehicle by hand and seat every collar before you suspect the controller.
Measure the battery with a meter rather than trusting the indicator lights. A pack can show four bars and still sit below the voltage the controller needs, and a pack whose protection circuit has tripped can read full while delivering nothing. Then follow the chain in order: battery, the connection to the controller, the controller, the motor.
An error code usually reports what the controller cannot talk to, not what is broken. Write the code down exactly, power off, reseat every connector in that system, and power back on — a surprising share clear right there. Then look the code up.
Two ordinary explanations. The pack may be aging, sagging under load in a way a resting voltage check will not show. Or the controller's speed or power settings were changed — by an owner, a previous technician, or a firmware update. Both are measurable; neither is a guess.
Stop. Do not charge it, and do not charge it indoors. A pack that took an impact can enter thermal runaway hours or days later while looking undamaged, so it gets stored outdoors or in a fireproof container, the customer gets told, and the finding goes in writing. This is the one place in the trade where there is no judgment call.
Check the pads before the cable. Below 1 mm of pad material they are replaced, full stop. Tension the cable against worn pads and the lever feels better immediately — which is the trap, because you have added no braking material and the customer now uses up that last millimeter faster.
Yes, and most people who take this course start with none. You need ordinary high-school math and science, somewhere to practice, and about 30 hours. The first module is free to read, so you can find out whether the material suits you before paying anything.
The steps for a swollen, hot or damaged lithium pack are the ones people forget at exactly the wrong moment. Our fire safety poster says them plainly, and anyone can order one — no enrollment, no account. Ask us for a poster.
The Shandoka technician certification takes someone with no experience and makes them capable on e-bikes, kick scooters, e-mopeds and electric motorcycles. About 13 hours of self-paced reading plus bench time, and Module 1 is free to read — start there and decide for yourself.
Running a shop rather than fixing your own ride? Training a whole team works differently — seats, records, and a guide for handing bench work over safely.
