Model GC318
L3 Service Manual
Phenomenon 2: CDMA part cannot power on, it caused the UIM card cannot be detected
：
Insert UIM card, and going to idle screen, if it can displaying “Insert UIM card”
，
but cannot check the
CDMA SW code by inputting *#0000#,it proves that CDMA part cannot power on.
STEPS:
1. Short circuit VBAT and VCHG to check whether the CDMA can power on or not. If it can power on, it proves
that the issue exists in the GC power key path.
2, Short circuit the VBAT and VCHG, if still cannot power on CDMA, it proves that the issue exists on the CDMA
itself. There is some possibility as below: High current, No current, current cannot be hold and the current is hold
at a certain step of powering on process only.
1
）
High current
Check VCHG, VBAT, S1
，
S2
，
VREG_MSMA, VREG_ MSME1, VREG_ MSME2,VREG-RUIM, VREG-RFA1,
VREG-RFA2, VREG_ MPLL,VREG_ XO whether the voltage is proper or not.
2
）
No current
1. Check the output voltage of CDMA CPU and check the soldering of resistance and capacitance, if there is
some problem about the soldering, just replace or re-soldering.
2. Try to download the SW
3. Current cannot be hold
4. Make the current of PS-HOLD high to hold the current, then check the XO
（
19.2MHz
），
VBAT, S1
，
S2
，
VREG_MSMA, VREG_ MSME1, VREG_ MSME2, VREG-RUIM, VREG-RFA1, VREG-RFA2, VREG_ MPLL,
VREG_ XO voltage one by one
，
if the voltage is not proper, fine the reason, If the voltage is proper, then check
the CPU.
5. Current is holding in a certain process of powering on
Phenomenon 3 CDMA can power on but it is displaying searching network all the time.
：
Inserted UIM card and power on the handset
displaying “Searching network” all the time
It proves that the UIM card is detected but the signal is
not good
Analyzing
：
1, CDMA RF slot not connected ,need to re-soldering
Re-soldering
2, CDMA antenna touched not properly
Assemble the antenna again
