[P8lite Q&A, Help & Troubleshooting] ffxx68:
Thanks for the suggestion. I guess I have the same problem with my just-1-year-old phone too and will need o send it for maintenance.

Just for the sake of completeness, I collected the logcat when trying to enable WiFi and found these messages (among others related to WiFi):

06-03 13:07:34.841 3131 3307 E WifiMonitor: startMonitoring connectTries sleep:100

06-03 13:07:34.943 3131 3307 E WifiHW : Supplicant not running, cannot connect

06-03 13:07:34.943 3131 3307 E WifiMonitor: startMonitoring connectTries sleep:200

06-03 13:07:35.145 3131 3307 E WifiHW : Supplicant not running, cannot connect

06-03 13:07:35.145 3131 3307 E WifiMonitor: startMonitoring connectTries sleep:400

06-03 13:07:35.547 3131 3307 E WifiHW : Supplicant not running, cannot connect

06-03 13:07:35.547 3131 3307 E WifiMonitor: startMonitoring connectTries sleep:800

06-03 13:07:36.349 3131 3307 E WifiHW : Supplicant not running, cannot connect

06-03 13:07:36.349 3131 3307 E WifiMonitor: startMonitoring connectTries sleep:1600

06-03 13:07:37.951 3131 3307 E WifiHW : Supplicant not running, cannot connect

...

06-03 13:07:42.974 3131 3307 E WifiStateMachine: Unable to change interface settings: java.lang.IllegalStateException: command '115 interface setcfg wlan0 0.0.0.0 0 down' failed with '400 115 Failed to set address (No such device)'

06-03 13:07:42.975 3131 3307 E WifiMonitor: killSupplicant p2ptrue init.svc.wpa_supplicant=unknown init.svc.p2p_supplicant=unknown

06-03 13:07:42.977 3131 3307 E wifi : Could not read interface wlan0 flags: 19

06-03 13:07:42.977 3131 3307 E WifiNative-HAL: Could not start hal

06-03 13:07:42.977 3131 3307 E WifiStateMachine: Failed to start HAL

06-03 13:07:42.977 3131 3307 E WifiHW : Ensure_old_config_file_exists:/data/misc/wifi/wpa_supplicant_hisi.conf, ret:-1 , errno=No such file or directory

06-03 13:07:42.977 3131 3307 E WifiHW : unlink file:/data/misc/wifi/wpa_supplicant_hisi.conf

06-03 13:07:42.977 3131 3307 E WifiHW : old wifi config file not exist or rename fail, will delete it and creat a new config file

06-03 13:07:42.977 3131 3307 E WifiHW : Ensure_config_file_exists:/data/misc/wifi/p2p_supplicant_hisi.conf, ret:0 , errno=No such file or directory

06-03 13:07:42.978 3131 3307 E WifiHW : Ensure_config_file_exists:/data/misc/wifi/wpa_supplicant.conf, ret:0 , errno=No such file or directory

06-03 13:07:42.978 3131 3307 E WifiHW : wifi_start_supplicant: last serial = 117440568

...

06-03 13:07:43.121 14525 14525 I wpa_supplicant: rfkill: Cannot open RFKILL control device

06-03 13:07:43.122 14525 14525 E wpa_supplicant: Could not read interface wlan0 flags: No such device

06-03 13:07:43.122 14525 14525 I wpa_supplicant: nl80211: Driver does not support authentication/association or connect commands

06-03 13:07:43.123 14525 14525 I wpa_supplicant: nl80211: deinit ifname=wlan0 disabled_11b_rates=0

...

06-03 13:07:43.223 14525 14525 E wpa_supplicant: Could not read interface wlan0 flags: No such device

06-03 13:07:43.224 14525 14525 W wpa_supplicant: get_dev_name failed,ioctl error:ret = -1

06-03 13:07:43.224 14525 14525 W wpa_supplicant: get_dev_name failed, ret = -1

06-03 13:07:43.224 14525 14525 E wpa_supplicant: wpa_driver_set_powermgmt_on failed ret=-1

06-03 13:07:43.224 14525 14525 E wpa_supplicant: wlan0: Failed to initialize driver interface

06-03 13:07:43.224 14525 14525 W wpa_supplicant: wapi_deinit_iface :wpa struct is null

06-03 13:07:43.225 14525 14525 E wpa_supplicant: exception handler create netlink failed! ret = -1

06-03 13:07:43.225 14525 14525 E wpa_supplicant: exception handler : netlink create failed, ret = -1

06-03 13:07:43.225 14525 14525 I wpa_supplicant: set current WIFI status to BT!