Teensy 4.1 Dead on Arrival

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a_sabater
 
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Teensy 4.1 Dead on Arrival

Post by a_sabater »

Hi,

I have a Teensy 4.1 (https://www.adafruit.com/product/4622) that I ordered on 6/17/2022 and arrived 6/24/2022 that I am pretty sure is dead on arrival. Got another Teensy on Adafruit to match the one I ordered from PJRC. I didn't test the device before soldering headers on it, but in the past, it would start a blink program once power was applied. The lights don't blink and I can't find an associated port when it's plugged in. I am pretty sure the device is defective.

Would it be possible to get a replacement? Please let me know if you need any more information.

Thank you!

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adafruit_support_mike
 
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Re: Teensy 4.1 Dead on Arrival

Post by adafruit_support_mike »

As a sanity check, verify your USB cable by using it to connect some other, known-working device to a computer.

There's a plague of charge-only cables out there with USB connectors at both ends, but no wires for the data signals. People get caught by them every day.

Just swapping cables has no diagnostic value. The current record is someone who had to try ten cables before finding one that worked. Only a working USB connection can rule out a charge-only cable.

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a_sabater
 
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Re: Teensy 4.1 Dead on Arrival

Post by a_sabater »

Hi Mike!

Thanks for the reply and suggestions! I am pretty sure that it's not the cable. Attached are two pictures. The Teensy on the left is one I borrowed from a friend. I'm able to program it with the USB cable I have been using for a while and run a blink program (see the light). The Teensy on the right is the one that I ordered on 6/17. I'm not able to program that one and the lights don't turn on.
LED on.jpg
LED on.jpg (544.78 KiB) Viewed 297 times
LED off.jpg
LED off.jpg (672.65 KiB) Viewed 297 times

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Re: Teensy 4.1 Dead on Arrival

Post by adafruit_support_mike »

That's a good comparison test.

What voltages do you see on the unresponsive board's 3V and 5V pins?

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a_sabater
 
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Re: Teensy 4.1 Dead on Arrival

Post by a_sabater »

Hi Mike,

Sorry for the delay. I wanted to borrow my friend's Teensy so I have a reference.

On my friend's Teensy, on the 5V and 3V pins, I measure 5.1V and 3.3V, respectively.

On my unresponsive Teensy, on the 5V and 3V pins, I measure 5.0V and 0.2V, respectively.

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Re: Teensy 4.1 Dead on Arrival

Post by adafruit_support_mike »

Thank you. That means there's probably a short in the microcontroller.

Send a note containing a link to this page and your order number to [email protected]. The folks there will get you a replacement.

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Re: Teensy 4.1 Dead on Arrival

Post by a_sabater »

Thanks for the support Mike!

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