Teensy 4.1 Dead

zopsi

New member
I was running a Teensy 4.1 with some code to perform an imperceptible mouse jiggle to the connected laptop.

Code:
void setup() { }
void loop() {
    Mouse.move(1, -1);
    delay(25);
    Mouse.move(-1, 1);
    delay(25);
}

After running this code for a few days off and on the Teensy 4.1 does not appear over USB and does not do anything on pushing the button. The Teensy was properly protected in an enclosure with no modifications.

My second Teensy works, but I'm worried it will die as well.

Any ideas?
 
What OS?

Pestering the computer 20 times a second with a pair of moves might have triggered it?

The Button should take the Teensy to Bootloader with a RED LED showing. If Teensy Loader is active with a usable sketch it will upload and restart the Teensy, otherwise it will then sit 'offline' with the RED LED ON that is normally off when running.

And there is the 15 second or 13-17 second Restore ... does that do anything
 
....does not appear over USB and does not do anything on pushing the button.
The button is NOT a reset button, but is used to put the Teensy into programming mode.
 
Pressing (and then releasing) the pushbutton on Teensy 4.1 should do *something*. You should at the first least observe something happen with the red LED located near the USB connector.

If you suspect your Teensy may be physically dead, the first thing to check is the voltage at the 5V (Vin) and 3.3V pins. This confirms whether it's getting power from the USB cable, and whether the power up sequence is working to the point of turning on the 3.3V voltage regulator.
 
Hi, I am facing the similar issue. The led did not blink anymore when I plugged in the usb cable. After search through the forum, I found out there is a short between 3.3V and ground. Does it mean the board was dead? Any solution for it? What is the potential cause?
 
Most likely the low dropout regulator. Is it the 8pins or the 6pins LDO as U4 on your dead T4? Teensy just a bare Teensy, or maybe something connected to the +3V3 and the +5V pins? They don’t like high capacitive loads (>>100 uF) on the 3V3 output in combination with low ohm resistive load on the 5V line, and then unplugging USB that supplied 5VUSB.
 
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