[Samsung Galaxy S9+ Questions & Answers] Youdoofus:
not sure how helpful this is, but here is a list of previously known service menu codes

https://drfone.wondershare.com/unlock/samsung-galaxy-secret-code-list.html

Samsung Galaxy Secret Codes to Test Functions

• Enter Light Sensor mode with this code - *#0589#

• Proximity Sensor - *#0588#

• Access all Wi-Fi Mac Address - *#*#232338#*#*

• For WLAN network - *#*#526#*#*

• For testing GPS - *#*#1472365#*#*

• Another test code for GPS testing - *#*#1575#*#*

• Diagnostic Configuration - *#9090#

• To troubleshoot Bluetooth - *#*#232331#*#*

• Enter Bluetooth Test Mode - #*3888#

• Audio Testing - *#*#0673#*#*

• Test your device screen - #*#0*#*#*

• Check Backlight and Vibration and perform other general tests - *#*#0842#*#*

• General Test Mode - *#0*#

• Audible - *#0673#

• Universal Test Menu - *#8999*8378#

• Mobile Time Testing in Real Time - *#0782#

• Vibration Motor Test - *#0842#

For Mobile Restarting

The following Samsung Galaxy Secret codes are used to restart your Samsung Galaxy device without doing it manually

• #*3849#

• #*2562#

• #*3876#

• #*3851#

For SIM Lock/Unlock

• SIM Unlock - #0111*0000000#

• Turn on Auto SIM Lock - #7465625*28746#

• Turn on Auto SIM Lock - *7465625*28746#

Getting Phone Information

• Get Your Device Info - *#*#4636#*#*

• View H/W, PDA and RFCallDate info on your phone - *#*#4986*2650468#*#*

• View Firmware Software version - *#*#1111#*#*

• View PDA type and version - *#*#1234#*#*

• View Firmware hardware version - *#*#2222#*#*

• Display ROM Sales code, change list number, and build time of your phone build - *#*#44336#*#*

• Reset user data and change sales codes - *#272*IMEI#

• View all user stats from very beginning and important phone info - *#*#4636#*#*

• View status info for GSM network - *#0011#

• Check hardware and software info - *#12580*369#

• Check All Hardware and software version of the device - #*#8377466#

System Control

• To Control USB Logging - *#872564#

• To enter Control Panel of USB I2C Mode - *#7284#

• Control Audio Loopback - *#0283#

• To control GCF Configuration - *#4238378#

• To Control and manage GPS menu - *#1575#

Check Service Mode andFirmware

• Get Ciphering info and enter service mode - *#32489#

• USB Service - #0808#

• Default Service Mode - *#197328640#

• Service Mode USB - *#9090#

• WLAN Engineering Service Mode - *#526#

• TSK/TSP firmware update - *#2663#

• Enter Camera Firmware menu - *#7412365#

• Update Camera Firmware - *#34971539#

• Sellout SMS/PCODE view *2767*4387264636#

• OTA update menu - #8736364#

Factory Reset

• Factory restore/reset for Samsung Smartphone with confirmation message - *#7780#

• Factory Reset without confirmation message - *2767*3855#

• Backup and copy media files - *#*#273283*255*663282*#*#*

Check Network

• Customize MCC/MNC Network Lock - *7465625*638*#

• Insert Network Lock and conduct network data locks - #7465625*638*#

• Customize Network Lock NSP - *7465625*782*#

• Insert any Network lock keycode (semi-partiality) - *7465625*782*#

• Insert Network Operator - #7465625*77*#

• Network Lock SP - *7465625*77*#

• Functioning and Network Lock for NSP/CP - *7465625*27*#

• Network insertion of Galaxy content provider - #7465625*27*#

• CSC Code of Galaxy S3 to get buyer code - *#272*IMEI#

• Choose the type of your network mode RF Band - *#2263#

For Debugging

• Dump Menu to dump RIL - *#745#

• General debug dump menu - *#746#

• Nand flash S/N - *#03#

• Provides option to improve phone network, battery life and Wi-Fi speed and view dump menu - *#9900#

• Auto Answer Selection - *#272886#

• Remap Shutdown and End Call TSK - *#03#