Ultrasonic sensor, strange reading


I have purchased a Starter kit and additional two ultrasonic sensors.

I have setup a test program that is running fine and the ultrasonic sensor that comes with the starter kit displays the reading in centimeters correctly.

But when I attached the two additinal sensor i bought, they dont behave as expected.
I just swapt the sensors without changing code or port.
but the reading goes dont to something like 0.522 when it should be something like 19,132

All three is V3 sensors.
I have tried to reset default program and update firmware.
I am using windows and program version 3.4.11

I cannot see any damage, bad solderings or broken parts on the sensors.
Are these sensors known to have issues?


This specific module should be faulty if it always changes between 0 and 1. You may turn to the shop for warranty service.


Yes it is jumping between different values between 0 and 1.
I will contact shop for.

thank you


I have just purchased an mbot ranger kit for my students and I’m following this to test the sensor. I get the distance reading while I’m connected with USB. I would like to keep the reading on the stage for a particular project. I replace the hat with Auriga and updated the firmware (with some additional code for sensing), then the sensor distance reading is lost? Does anyone know if I can still get the sensor reading when disconnected from USB. This is all very knew to me!


In order to let panda say out the value, we have to keep computer/mBlock connected with the robot so as to run online program. There are these methods:

  1. USB connection, supports update, reset, upload, and run online program;
  2. Bluetooth module +makeblock bluetooth dongle, supports upload program and run online program;
  3. 2.4G (included module and dongle), supports run online program only;
  4. Try mBlock 5 latest version which may support some computer built-in Bluetooth adapter (with ranger Bluetooth), supports run online program only; this method can refer to this post.

If you have other electric module like tft lcd display or segment-display, they can show value.


Many thanks tech support. I will try these options and let you know how I go.


Sure, no problem.


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