(No.RA075<Rev.001>)1-57
SECTION 5
TROUBLESHOOTING
5.1
Fault Diagnosis of the BGA (Ball Grid Array) IC
Overview
A flowchart for determining whether or not the transceiver can be powered on (the LCD does not function even if the power switch
is turned on) due to broken BGA parts.
BGA parts
MPU/DSP (IC706), mobile DDR (IC702), Flash memory (IC701)
When the BGA IC is problematic, please bring the printed circuit board (XCA-074F-00) in for service. Various ESN/ default adjustment
values are written on the printed circuit board for service.
Additionally various ESN stickers are included. (Please refer to "5.4 Replacing Main Unit".)
After the printed circuit board has been readjusted, please attach any ESN stickers to the chassis.
When "ESN Validation" is used, you must modify the ESN register.
Checking power supply voltage
Checking voltage
Points to be checked
Points to be checked
Points to be checked
Points to be checked
Normal voltage
The ignition key is kept ON.
Points to be checked
Normal voltage
Normal voltage
Normal voltage
1.2V
19.2MHz
12M C39
1.8V
18M C64
3.3V
1.8V
3.1V
33M IC5 (5pin)
1.8V
18M_3 IC9 (1pin)
Power supply of each device is connected through the coil.
[MPU/DSP]
12M : L714, L715, L717
18M : L720, L721
33M : L722
[mobile DDR]
18M : L702
[Flash Memory]
33M: L700
18M_3: L724
Checking the clock
Checking the clock
Normal voltage (1.2V)
19.2MHz
MPU/DSP side R708
Pass
Pass
Pass
Pass
Checking the Reset/Control signal
Checking the control signal input to the MPU/DSP
/RST D12 (Anode side)
/BINT IC2 (13pin)
The POWER key is pressed and held.
Checking the MPU/DSP input switch signal
The BGA parts are not broken.
Check the peripheral circuit of IC2.
*2
(Page 1-59)
The BGA parts are not broken.
Checking for an abnormal point
12M has an abnormal voltage.
[MPU/DSP]
Remove L714 and L715 and L717 to check
the voltage of the 12M.
If the voltage becomes normal, the MPU/DSP
is broken.
Note:
A1(12M DC/DC Converter Device) is fragile
in the scratch.
Be careful when you touch this parts.
18M has an abnormal voltage.
[MPU/DSP]
Remove L720 and L721 to check the voltage
of the 18M.
If the voltage becomes normal, the MPU/DSP
is broken.
[mobile DDR]
Remove L702 to check the voltage of the 18M.
If the voltage becomes normal, the mobile DDR
is broken.
33M has an abnormal voltage.
[MPU/DSP]
Remove L722 to check the voltage of the 33M.
If the voltage becomes normal, the MPU/DSP
is broken.
[Flash Memory]
Remove L700 to check the voltage of the 33M.
If the voltage becomes normal, Flash memory
is broken.
18M_3 has an abnormal voltage.
[Flash Memory]
Remove L724 to check the voltage of the
18M_3. If the voltage becomes normal,
Flash memory is broken.
If the voltage is not corrected, there is a
problem other than the BGA parts.
*1
(Page 1-59)
Fail
Fail
Fail
Fail
/OVRB_OUT IC2 (12pin)
3.1V
/IGN_OUT IC2 (9pin)
ON : 0V
ON : 0V 3.1V
/PSW_OUT IC2 (15pin)
ON : 0V
ON : 0V 3.1V