[Epic 4G Android Development] ghostrid3r:
Disclaimer: I do not take responsibility for any problems that may result from the use of these codes. In other words, use at your own risk!!!

To use these codes, you simply open up your phone dialer, and type them in.

*#1472365# - GpsSetup

Very useful tests for the GPS!!!

Setup/Position Mode/ Operation Mode: (Standalone/MSAssisted/MSBased) Starting Mode: (Cold Start/Warm Start/Hot Start) Session Type: (Single Fix/Navigation) Setup/Command allows you to test the GPS and look at the results

*#INFO*1111# - Testing

Phone information/Battery information/Battery history/Usage statistics

Very useful diagnostics

*#0*# - LCD TEST

red/green/blue/melody/vibration/dimming/megacam/Sensor/touch/sleepmode/LED/RECEIVER

Very useful tests for the LCD

##RTN# - Real-Time Network (RTN)

Lots of useful information, like the Life timer / calls and Life Byte usage stats

*#DATA*727336*# - DataCreate

Call log/System Space/User Space/Phone Book/Schedule/Message/Ring tone/Screen/IMEI/ESN/Error log

Very useful information!!!

*#0228# - BatteryStatus

Very useful real-time battery statistics!

##UPST# - PhoneUtil - UART/USB

Universal Asychronous Receiver/Transmitter / Universal Serial Bus

Most likely controls how you connect technician testing equipment to test out the UART/USB subsystems

##DATA# - Data Programming - Requires MSL

User Name/Advanced/Restore/Enable HFA/DSA Server/MMSC/URL/Multimedia/WorkMode/WiMAX

I don't have my MSL (Master Subsidy Lock) code, so I can't test this

##DEBUG# - Debug Menu - Requires MSL

Debug Screen/Test Calls/RC Data/HDR/1X Selection/Voice Privacy/DTMF Set/Korea Mode Set

I don't have my MSL (Master Subsidy Lock) code, so I can't test this

##AKEY# - Data A key menu - Requires MSL

I don't have my MSL (Master Subsidy Lock) code, so I can't test this

##<MSL># - Master Subsidy Lock - Requires MSL

Program your Mobile Device Number(MDN) and Mobile Station ID(MSID)

The <MSL> is your phone's Master Subsidy Lock, a 6 digit code, you can sometimes get it from Sprint

##GPSCLRX# - Reset the GPS - Requires MSL

I don't have my MSL (Master Subsidy Lock) code, so I can't test this

##SCRTN# - Changes DSA back to Factory - Requires MSL

I don't have my MSL (Master Subsidy Lock) code, so I can't test this

##TTY# - TTY TestMode

*#0842# - Device Test - Vibration Test

*#0673# - MelodyTest

*#7780# - Factory data reset

*#232331# - BluetoothTest

*#2664# - Touchscreen Accuracy Test

Nice if you want to see how accurate your touchscreen is

*#0283# - ServiceMode - PACKET LOOPBACK

Need to hit home to get out - I couldn't get this to do anything but it could be the data packet that you sent coming back to you on the loopback device

*#767*3855# - Factory Format - WARNING!!!

Will go to Hands Free Activation

Nice if you'd like to reactivate your phone, it will do so automatically

*#197328640# - ServiceMode - Menu key to bring up menu - WARNING!!!

Will turn off your radio - Not sure what this does

*#0011# - ServiceMode - Force Closes - Menu key to bring up menu

Will turn on your radio, and then reboot

*#32489# - ServiceMode - Force Closes - Menu key to bring up menu

Doesn't seem to affect the radio

*#2580# - ServiceMode - Not sure what this does

*#0782# - RTCTimeRead - Displays Date and Time

*#745# - Sec_RIL_Dump - Has the LogFileList

Copy to phone memory/Copy to SD card(grayed out)/View Ril Log(grayed out)/Clear Ril Log/Exit

Probably dumps the logs for the Radio Interface Layer (RIL) between the Operating System and the phone's radio and modem

I haven't tested a dump yet

*#9900# - SysDump

copy logcat/dumpstate/dumpsys/enable debug log/copy/watchdogdumpstatelog

Probably dumps the logs for the Operating System kernel

I haven't tested a dump yet

This has been posted several times, but I thought it might be useful for some people who may not have seen it.

To get into the Android system recovery/Samsung Recover Utils

Turn off phone, hold volume down, the power button, and the camera button at the same time to enter the recovery partition, and recover the phone

Use Volume keys to move among options, and the Home key to select

reboot system now

apply sdcard:update.zip - Manually update from your SD card

wipe data/factory reset

wipe cache partition - Didn't do anything for me

I hope you find this to be useful information. Feel free to add other codes you have discovered, or correct any misunderstanding I may have about what a certain code does.