Power Does Not Stay On (Refer To Vreg_Out Circuit) - Nokia 3806 Service Manual

2. Soldered joints are OK.
3. ASIC orientations are OK.
Secondly, follow below instructions to do the troubleshooting for the specific circuitry failure. All failed
symptoms are categorized into following sections:
Power Does Not Stay ON
Audio Faults
Display Faults
Keypad Faults
No Vibration
USB Interface Disabled
FM Disabled
UIM Card Faults
T-Flash Card Faults
Camera Faults
Charging disabled
Note:
1. The Shielding Case Assy can not be reused after removal.
2. After using the heat gun, domesheet needs to be replaced.

Power does not stay on (refer to VREG_OUT circuit)

Below four cases which may cause this failure: big current, no current, no holding current and no
program in memory.
Case One:
Big current appears when power is fed to Vbattery or "power on" key is pressed on the handset.
1. Check if the following voltages of PMIC are normal:
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Baseband Description and Troubleshooting
RM-583
Issue 1