Ericsson I 888 Trouble-Shooting Instruction page 25

GND
DCIO
V704
Check the feed voltages VDIG (3.2 V) on the side that is marked of C600 (Fig 6.2)
and VRAD (3.8 V) on N450:13 (Fig 6.1) and measure the resistance of R703 (class
A, 0 Ohm, Fig 6.2). If any of the feed voltages ar incorrect, proceed to chapter 3
("Doesn´t start"-fault). If the feed voltages are correct, send the phone to the next
repair level.
R703
6.3 Doesn´t begin to charge.
Open the phone and check for liquid damages. Make sure the system connector pads
are not burned or oxidized, especially on GND pin 10 (Fig 6.1). Measure the resist-
ance between DCIO and VBATT (390 Ohm, Fig 6.1). If the resistance is too low,
replace V401 (class A, Fig 6.2). If it is too high, measure the resistance of R421 (0.1
Ohm, class B, Fig 6.2). Measure the resistance of R411 (390 Ohm, class A, Fig 6.2).
If R421 and R411 are correct and the resistance between DCIO and VBATT is still
too high, is there a foil damage and the board has to be discarded. Give the board
power and start it by grounding N450:6 (Fig 6.1). If it doesn´t start, replace V401
(class A). If that didn´t make it, replace V704 (class A, Fig 6.1).
4-00021-2/FEA 209 544/5.C
I888, Standard Electrical Repairs
VBATT
N450
Fig 6.1
C600
Fig 6.2
1
20
10 11
V401
R411
R421
25
(42)