Please help to read voltage values with below steps:
#on host, copy below firmware to /lib/firmware of tegra b
~/nvidia/nvidia_sdk/DRIVE_Software_10.0_Linux_OS_DDPX/DRIVEOS/drive-t186ref-linux/targetfs_b/lib/firmware/DRIVE-V5.1.x-E3550-NV-Aurix-UPDATE-StepA-1.29.10.hex
~/nvidia/nvidia_sdk/DRIVE_Software_10.0_Linux_OS_DDPX/DRIVEOS/drive-t186ref-linux/targetfs_b/lib/firmware/DRIVE-V5.1.x-E3550-NV-Aurix-IFW-StepA-1.29.10.hex
#on target
$ nv_aurix_update -i /lib/firmware/DRIVE-V5.1.x-E3550-NV-Aurix-IFW-StepA-1.29.10.hex -u /lib/firmware/DRIVE-V5.1.x-E3550-NV-Aurix-UPDATE-StepA-1.29.10.hex -f 1
#in aurix console
showvoltages