Recovery over USB

The last resort for a WiCAN PRO whose flash is corrupted: a firmware that does not start, a device that does not even reach safe mode, an update that was cut off half way. The whole firmware is written again over the USB-C cable with Espressif's flashing tool, and the flash is erased on the way, so the device starts as new.

Try the gentler ways first. Factory reset has safe mode, which recovers from a bad configuration and from a firmware that crashes at start with nothing but the button. USB flashing is for when safe mode does not come up either.

You need

A USB-C data cable, a computer, power for the device from its OBD-II plug (the car, or a bench supply: the USB-C port does not power WiCAN PRO), the firmware zip from the releases page, and the flashing tool

The files

The four files in the zip: bootloader.bin, partition-table.bin, ota_data_initial.bin and the firmware wican-fw_obd_pro_vXXX.bin

The tool

ESP Tool in the browser at https://espressif.github.io/esptool-js/ (Chrome or Edge), or esptool.py on the command line (pip install esptool)

Keeps

The SD card only. The erase wipes the settings, the files (vehicle tables, certificates, scripts, the dashboard, DBC files), the Bluetooth pairings and the crash report

Get the files

Releases are at https://github.com/meatpiHQ/wican-fw/releases. The zip of a release, wican-fw_obd_pro_vXXX.zip, holds the four files. The .bin published on its own is for the web interface's update and is not enough for a recovery. A pre-release may come without a zip: flash the latest release, then update to the pre-release from the web interface.

Install the serial driver

The USB-C port of WiCAN PRO is a WCH CH342 dual serial converter. Windows needs WCH's CH343SER driver from https://www.wch-ic.com/downloads/CH343SER_EXE.html (it covers the CH342). WCH's drivers for macOS and Linux are at https://github.com/WCHSoftGroup/ch34xser_macos and https://github.com/WCHSoftGroup/ch343ser_linux; check first whether your system shows the two ports without them.

Connect

1. Power first. Plug WiCAN PRO into the car's OBD-II port, or a bench supply on the plug. It does not run from USB.

2. Then the USB-C cable to the computer. Two serial ports appear: use the first one, Serial-A. Windows lists them in the Device Manager as USB-Enhanced-SERIAL-A and USB-Enhanced-SERIAL-B with their COM numbers; Linux and macOS show two serial devices as well, Serial-A being the first of the pair.

3. Open the tool: https://espressif.github.io/esptool-js/ in Chrome or Edge, Connect, pick the Serial-A port in the browser's dialog. The page then says Connected to device: ESP32-S3.

Erase and flash

1. Erase Flash. This is what makes it a recovery: a corrupt configuration, a half-written update, whatever is wrong in the flash goes with it. It takes a few seconds.

2. Add the four files, one row each, with these addresses:

   File	Address
   bootloader.bin	0x0
   partition-table.bin	0x8000
   ota_data_initial.bin	0xd000
   wican-fw_obd_pro_vXXX.bin	0x10000

3. Program. The log under the buttons shows the four writes. The firmware is the long one, about a minute at 921600 baud.

4. Unplug the USB cable, then power the device off and on (out of the OBD-II port and back in). It starts as a new device: join WiCAN_<device id> with @meatpi# and run Quick Setup. A firmware newer than the zip you flashed goes on afterwards from the web interface, see Update.

ESP Tool in the browser, ready to program. The picture comes from the legacy documentation; the file in the last row is the firmware of the release you flash.

With esptool.py

The same from the command line, with the name of your Serial-A port:

esptool.py --chip esp32s3 --port COM5 erase_flash
esptool.py --chip esp32s3 --port COM5 write_flash 0x0 bootloader.bin 0x8000 partition-table.bin 0xd000 ota_data_initial.bin 0x10000 wican-fw_obd_pro_vXXX.bin

Leave out the first line only when the flash is not the problem and the settings are worth keeping. For a recovery, erase.

Troubleshooting

Symptom	Likely cause	What to do
No serial port appears	a charge-only cable, no driver, or the device is not powered	a data cable, the driver, OBD-II power before the cable
Two ports, and the tool does not connect	the second port, Serial-B, was picked	pick Serial-A; if in doubt, try the other one
Failed to connect	the tool did not catch the chip	unplug the USB cable and plug it in again, then Connect at once
The write stops half way	a loose cable, or the supply dropped	the cable; a steady supply on the OBD-II plug
ESP Tool says the browser is not supported	Firefox or Safari	Chrome or Edge, which have Web Serial
The device starts and asks to be set up	expected after an erase	Quick Setup, then a backup if you have one