Diagnosis Map - Panasonic Toughbook CF-28 Service Manual

4.4. Diagnosis Map

4.4.1 MAIN UNIT DIAGNOSIS (1/2)
Make sure that connecting cables, connectors and AC adapter are not loose or disconnected prior to
testing.
No. Symptom
1 No power is sent to the
unit.
No power is sent to the
unit, (When using the
Battery Pack)
2
Power cuts off during
operation.
4.4.2 MAIN UNIT DIAGNOSIS (2/2)
Make sure that connecting cables, connectors and AC adapter are not loose or disconnected prior to
testing.
No. Symptom
1
When a device is selected
for "Boot Up Drive", the
system boots from a
different device.
2
Date or Time cannot be
input.
Date and Time does not
change properly.
Date and Time are not
displayed.
3 Memory count is too large
or too small.
Troubleshooting
procedures
No.
Is 15V applied to pins 5-8 of
1-1
Q53? (Whichever one)?
Is voltage pin 4 of Q53 lower
1-2
than 1V?
Before setting the power
switch to ON, check voltage
1-3
on either side of R372. Is
Voltage 3.3V?
1-4 Final Means
Is 8~11.4V applied to pins
1-5
1~3 of Q50? (Whichever one)
Check soldered parts of
2-1
R355, 356, 365 and R367.
Troubleshooting
procedures
No.
Are there system files in the
1-1
device selected?
Does the unit operate
1-2 normally after replacing the
problem device.
2-1 Replace the Main PCB.
3-1 Replace the Main PCB.
4 - 5
Source of
Component
problem
Result
YES Go to No. 1-5
NO Go to No. 1-2
YES
NO
If lower than 15V
If voltage is 0V
during the power
YES switch is set to
ON, go to No. 1-7
If not 0V POWER SW
If voltage of
NO C404 is 3.3V
If lower than 3V
Main PCB
YES Go to No. 1-3
NO Go to No. 1-2
If they show
R355, R356
NO soldered
R365, R367
completely
YES
Source of
Component
problem
Result
YES Go to No. 1-2
NO Improper setting
Device for which
YES the problem
occurred
NO Main PCB
(FDD/SDD)
Main PCB
RTC battery
Main PCB
IC20
AC Adapter
D19, D20
D21, D22
R372
IC74
IC74
IC74
(HDD)
IC43
IC43
IC47
IC43
X2
IC35~IC41
IC80~IC83
IC33