My VOXL 2 will not boot and remains in QDL mode even with SW2 in the OFF position.

[Leon Gurevich]

Hello ModalAI team,

My VOXL 2 will not boot and remains in QDL mode even with SW2 in the OFF position. Could you advise whether there is an approved recovery/diagnostic procedure, or whether the board requires an RMA?

Confirmed details:

Chip marking: QRB5165M; recovery image: M0054(154)-1.zip.
Powered through a ModalAI power module.
SW2 checked with a multimeter: no continuity when OFF.
Ubuntu host; modal-qdl repository commit 136f4b7 (2026-03-06).
Repeated recovery attempts fail at the same point. USB connection and Sahara programmer transfer complete, and Firehose starts, but opening UFS LUN 0 fails.
The log reports:

Can't decode attribute slot with value
Failed to initialize (open whole lun) UFS Device slot 0 partition 0
Failed to open the device:3 slot:0 partition:0 error:0
Failed to open device, type:UFS, slot:0, lun:0 error:3
qdl: firehose operation timed out
[PROGRAM] failed to setup programming
Flash flat build failed
The web interface incorrectly displays a green success message despite these log errors. The full captured log is attached. It reports chip serial 456372656 (0x1b33b1b0); this is the programmer-reported chip identifier, not a confirmed board-label serial number.

Can this indicate recoverable UFS configuration/provisioning, or should the board be inspected for a storage/power fault? Please advise on the appropriate next diagnostic step or repair/RMA process.

Thank you,
Leon GurevichVOXL2-QDL-failure-log.txt

[tom]

@leon-gurevich , thanks for the detailed log.

The log shows the processor, memory and USB link are working, since the board loads and runs the Firehose programmer. The failure is the step after that: the programmer cannot open the UFS storage at all (LUN 0, error 3), so nothing is written. The flat build only writes partitions and cannot reconfigure the storage chip, so repeating the flash will give the same result. The "Can't decode attribute slot" line is a debug message and not the cause.

You're right about the green message, the web UI reports success even when the flash fails. Thanks for flagging it. The log ending in "Flash flat build failed" is the real result. We've updated the guide to say so: https://docs.modalai.com/voxl2-unbricking/#if-the-flash-fails-to-open-ufs

This needs an RMA. Please contact us at https://www.modalai.com/pages/contact-us with the serial number from the board label and your QDL log, and reference this thread.