LG Phones G Series G4

LG-H815
The LG-H815 is the international model of the LG G4. = Flow =

Checking XO Block
Output frequency = (19.2MHz). X4100 is used as the reference. one of WTR3905 and PM8994 internal VCO.
 * Check TP1 - Is it 19.2MHz?
 * Yes - move to next flow
 * Replace X4100 and then check TP1
 * Yes - move to next flow
 * Logic Troubleshooting

Transceiver DC Power Supply Circuit

 * Check TP1 +1V_RF is OK?
 * No - Logic Troubleshooting
 * Check TP2 +1.8V_RF is OK?
 * No - Logic Troubleshooting
 * Next flow

DC-DC Block

 * Check TP1(+VPA0) 0.5V < TP4 < 4.2V ?
 * No - Check U1400 (Physical Damage / soldering condition)
 * Next flow

ASM/FEMiD Block

 * Check TP1, TP2 High Level? (2.5V<TP1 <3.1V) and (1.7V<TP2 <1.9V)
 * No - Logic Troubleshooting
 * Check U1201 (Physical Damage / soldering condition)
 * Bad - Replace U1201
 * Next flow

GSM850/900/1800/1900 Rx

 * Check TP1/2/3/4 Signal exist?
 * No - Check Component above RF signal path
 * Check Transceiver (Physical Damage / soldering condition)
 * Bad - Replace U1500
 * Next flow

GSM850/900/1800/1900 Tx

 * Check TP1 +VPWR OK?
 * No - Logic Troubleshooting
 * Check TP2 3.2V<TP2<4.2V?
 * No - Check DC-DC Block again
 * Check TP3/4 - If GSM850/900 over 31dBm? If DCS/PCS over 28dBm?
 * Yes - Check component above RF signal path
 * Check TP5/6 - If GSM850/900 over 9dBm? If DCS/PCS over 7dBm?
 * No - Check U1301 (Physical Damage / soldering condition)
 * Check Transceiver (Physical Damage / soldering condition)
 * Bad - Replace U1500
 * Next flow

WCDMA (Rx signal path(B1/B2/B5/B8))

 * Check TP1/2/3/4 Signal exist?
 * Check U1201
 * Check Transceiver (Physical Damage / soldering condition)
 * Bad - Replace U1500
 * Next flow

WCDMA (DRX RF signal path (B1/2/5/8))

 * Check TP1/3/5/7 Signal exist?
 * No - Check SW1106 (Physical Damage / soldering condition)
 * Check TP2 exist
 * No - Check B1 FL1100 (Physical Damage / soldering condition)
 * Check TP4 Signal exists?
 * No - Check B2 FL1124 (Physical Damage / soldering condition)
 * Check TP6 Signal exists?
 * No - Check B5 FL1131 (Physical Damage / soldering condition)
 * Check TP8 Signal exists?
 * No - Check B8 FL1116 (Physical Damage / soldering condition)
 * Check Transceiver (Physical Damage / soldering condition)
 * Bad - Replace U1500
 * Next flow