About 90% of "no power at all" cases are actually loose or corroded connectors; the main motor plug or 12-pin pin retraction is a common root cause.
The most common repair report dealers receive is "the whole bike has no power and nothing happens when pressed". Field data shows that about 90% of these so-called "dead" bikes are not truly failed motors or batteries but connector problems.
Two root causes dominate. The main motor high-current plug loosens from vibration, and the 12-pin signal pins retract after repeated mating, causing poor contact. Moisture and salt spray accelerate pin corrosion, so the weak connection suddenly cuts out under high load.
These faults are hidden and recurring. Users often misread them as battery failure, which causes unnecessary battery returns and warranty claims.
QERYU engineering concentrates on connector protection. We use locking waterproof high-current plugs, add a secondary latch and anti-retraction structure to the 12-pin pins, and apply IPX6 sealing and anti-salt-spray treatment to all exposed interfaces. This attacks the "dead bike" rate at its source.