Yamaha PW error codes

Display A alternates between the normal screen and “Er” with a number and description, Display C shows “ER” with text, and Interface X shows faults only with light colours. The newest motors (PW-X3 and others) have no public code list of their own.

Trolda cannot read Yamaha PW motors yet. The code list is here to help you anyway.

Number code (Display A and C)

Code	Part	What it means
12	Display	The display has lost contact with the drive unit
13	Communication	The display and drive unit don’t match or can’t talk to each other
31–37	Torque sensor	The torque sensor (measures how hard you pedal) has a break, short or wrong voltage
38	Sensor	The motor’s current sensor (phase U) shows a wrong voltage while the motor is still
39	Sensor	The motor’s current sensor (phase W) shows a wrong voltage while the motor is still
61	Motor	Too much or abnormal current in one of the motor phases
62	Motor	Abnormal current in the motor that a restart doesn’t clear
63	Motor	Memory fault in the drive unit’s controller (stored data can’t be read)
64	Temperature	The drive unit electronics are too cold (below −20 °C) or too hot
66	Motor	Memory fault in the drive unit’s controller (stored data can’t be read)
67	Motor	One of the motor wires (one phase) is disconnected
68	Motor	Break or short in the motor’s position sensor (which tracks its rotation)
71	Battery	The drive unit isn’t getting proper data from the battery
73	Battery	The battery voltage is too high
74	Battery	Internal fault in the battery; its lights may blink oddly
79	System	Fault in the drive unit’s voltage converter (DC/DC)

No number code (display signs)

Code	Part	What it means
Er / ER	System	A fault in the e-bike system; the display shows “Er” or “ER” and a short description
ER BATTERY	Battery	Battery fault; Display C shows “ER” and “BATTERY” with a description
Interface X	System	Interface X: battery lights go out and the assist lights blink red – system or battery fault
—	Speed sensor	The speed sensor gets no proper signal; speed is missing and the field or lights blink
—	System	Not a fault: the system is checking itself, so the field blinks and assist pauses briefly
—	Motor	The automatic mode indicator blinks (right light turquoise on Interface X): possible drive unit fault
Interface X	Motor	Interface X: right light glows purple – walk assist has stopped

Sources

Explained in Trolda's own words from the manufacturer's public documentation. Trolda is not affiliated with the manufacturer. If in doubt, ask your dealer.

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