Motor Troubles

If you twist the throttle and the motor won’t go past 10 mph while making a clicking sound, it’s most likely a hall sensor issue and-but follow the steps below to be sure.

Backup Hall Sensor Connector

If switching to the backup hall sensor doesn’t fix the issue, your controller might be the culprit. Other factors could be at play, but this is a solid starting point. If the hall sensor is the problem, be prepared-it’s a tricky fix, and I’ll cover it in a future post.

The Checklist

Before stressing, check these quick fixes-plus, use the controller app (AC Aduser) to spot real-time errors by fowlloing the intructions on the “ONYX RCR Controller Programming” post !

  • Inspect motor wires near the motor for cuts or exposed sections.
  • Check rear brake disc-make sure it’s not dragging on the caliper.
  • Torque main axle nuts to 80Nm with a 24mm wrench.
  • Open the side panel and check the yellow phase wire junction box.
  • Peek inside at the controller-if the LED is flashing red, check the codes below!
  • Trace all main harness wires inside the body-look for anything loose or damaged.

Controller LED Codes

When your bike is on and functioning properly, the controller LED will be solid green. If you see a flashing red light on a small white or black dongle, that’s just the Bluetooth module and can be ignored. To check the controller LED, remove the left-side driver side panel and look towards the back of the controller.

Flashing RED Controller LED

If the controller LED is flashing red in a countable pattern, such as three flashes, a pause, then two flashes, it indicates a 3-2 error code. Refer to the table below to see if your error code matches any listed.

Flashing Explanation Solution
1,2 Over voltage error Battery voltage is too high for the controller. Check battery volts and configuration. Regeneration over-voltage.
2,4 Throttle error at power-up Throttle signal is higher than the preset dead zone.
3,2 Internal reset May be caused by some transient fault condition like a temporary over-current, momentarily high or low battery voltage. This can happen during normal operation.
3,4 Angle sensor error Speed sensor is damaged or defective.Or feedback signal is erratic.
4, 4 Hall Galvanometer Hall galvanometer device is damaged.

Service or Water Damage

If your ONYX was submerged in water above the pedal crank, allowing a pool of water to seep into the main body, or if a pressure hose was used for cleaning, there’s a good chance of internal damage. If your ONYX was recently serviced for a rear tire change or modification, it’s worth checking in with the shop or person who did the work.

The John Angel Test Method

This is a fairly reliable way to check if a hall sensor is bad. Simple, fast, and straight to the point! But to be sure, I recommend double-checking with the other methods listed in this post.

  • Turn on your ONYX.
  • Do not touch the throttle or brakes.
  • Lift your rear tire off the ground.
  • Spin the tire foward by hand.
  • No speed reading on the odometer? Bad hall sensor or controller!
  • Remove the side panel, switch to the backup hall sensor, and repeat the steps.

Method 1: Multimeter Test

To test if your QS Motor 205 V3Ti, 260, or 273 has a bad hall sensor, follow these steps:

Tools Needed

  • A multimeter (set to DC voltage or continuity mode)
  • A power source (bike’s controller or external 5V supply)
  • A hall sensor tester (optional but useful)
  • A small magnet (for manual testing)

Identify the Hall Sensor Wires

  • Red = +5V (Power)
  • Black = Ground
  • Yellow, Green, Blue = Hall Signal Wires

Power the Hall Sensors

  • Connect the motor hall wires to the controller and turn the bike ON.
  • If testing externally, apply 5V to the red wire and connect the black wire to ground.

Test Each Hall Signal

  • Set your multimeter to DC voltage.
  • Place the black probe on the ground wire (black).
  • Place the red probe on one of the hall signal wires (yellow, green, or blue).
  • Slowly rotate the motor wheel (or manually move a magnet across the sensor).
  • The voltage should toggle between 0V and 5V as the wheel moves.

Repeat for All Three Hall Wires

  • If any hall sensor stays stuck at 0V or 5V and doesn’t change, that sensor is likely faulty.
  • Plug the hall sensor wires into a hall tester.
  • Power the motor.
  • Spin the wheel slowly.
  • The tester should flash LEDs for each hall sensor.
  • If one LED stays on or off, that sensor is bad.

Signs of a Bad Hall Sensor

  • Good: Voltage toggles 0V → 5V as the motor spins.
  • Bad: Stuck at 0V or 5V, no voltage change.
  • Intermittent: Works sometimes, then fails-could be a loose connection or failing sensor.

If a hall sensor is bad, you’ll likely notice motor jerking, stuttering, or not starting properly. You may need to replace the faulty sensor by soldering in a new one.