so. I flashed both system and diags from ixtab's repository with fastboot.
I entered diags mode, with doesn't launch completly. Here is a log of the end of the boot sequence
Code:
[ 1.874759] ADC value out of thermistor range! setting display temp to 3 deg C
[ 2.017818] KERNEL: I pmic:charger chgina::charger connected
[ 2.027778] emmc: I def:mmcpartinfo:vendor=toshiba, host=mmc0:
[ 2.051011] MAX77696 Main Charger Driver 1.0.0 Installed
[ 2.057084] mmc0: unrecognised EXT_CSD revision 7
[ 2.061817] mmc0: error -22 whilst initialising MMC card
[ 2.079840] MAX77696 Energy Harvester Driver 1.0.0 Installed
[ 2.097718] Freeing init memory: 1036K
3.0.35-lab126 #1 Tue Sep 3 03:12:16 PDT 2013 armv7l
[ 2.258141] emmc: I def:mmcpartinfo:vendor=toshiba, host=mmc0:
[ 2.294617] mmc0: unrecognised EXT_CSD revision 7
[ 2.299367] mmc0: error -22 whilst initialising MMC card
[ 2.406435] add wake up source irq 104
[ 2.529739] emmc: I def:mmcpartinfo:vendor=toshiba, host=mmc0:
[ 2.561138] KERNEL: I pmic:fg battery init::mg config init successful
[ 2.568798] max77696-battery max77696-battery.0: Voltage alert 3400mV ... 4260mV
[ 2.577253] max77696-battery max77696-battery.0: SOC alert (disabled)
[ 2.589098] mmc0: unrecognised EXT_CSD revision 7
[ 2.593827] mmc0: error -22 whilst initialising MMC card
[ 3.527134] KERNEL: I pmic:fg battery id check::wario_battery_valid=1
[ 62.040090]
[ 62.040099] ADC value out of thermistor range! setting display temp to 3 deg C
I guess this
[ 2.299367] mmc0: error -22 whilst initialising MMC card is my next clue. Even if I'm... not very enlightened

. I don't know were to go from this point...
If you have (again) a pointer, I'd thrilled.
Thanks again