Ericsson I 888 Trouble-Shooting Instruction page 18

4.4) and R805 (15 kOhm, class A, Fig 4.4). Measure the resistance of C835 (>1
kOhm, class A, Fig 4.4) och C817 (>100 kOhm, class A, Fig 4.4), C810 (>10
kOhm, class A, Fig 4.4) and C812 (>100 kOhm, class A, Fig 4.4). If the fault
remains, send the phone to next repair level.
4.6 The handsfree is not detected.
Check the connection surface at the system connector. If they are fine, open the
phone and check for liquid damages, especially at the system connector pads. Chekc
the solderings on D600:67 and 70 (Fig 4.4). Measure the resistance of R635 (22
kOhm, class A, Fig 4.1) and R636 (22 kOhm, class A, Fig 4.4). Measure the resist-
ance of R601 (1 kOhm, class A, Fig 4.4) and R605 (1 kOhm, class A, Fig 4.1). If the
fault remains replace D600 (class B, Fig 4.4), if that doesn´t help - send the phone to
next repair level.
4.7 Microphone and earphone fault.
Check the connection surface at the system connector. If they are fine, open the
phone and check for liquid damages, especially at the system connector pads. Check
the solderings on D600:67 and 70 (Fig 4.4). Measure the resistance of EXTAUD
(Fig 4.5) to ground, if the resistance is lower than 10 kOhm, replace F600 (class A,
Fig 4.1).
Measure the resistance of PORTHF (Fig 4.5) to ground, if the resistance is lower
than 10kOhm, replace F602 (class A, Fig 4.1). Measure the resistance of R635 (22
kOhm, class A, Fig 4.1) and R636 (22 kOhm, class A, Fig 4.4). Measure the resist-
ance of R601 (1 kOhm, class A, Fig 4.4) and R605 (1 kOhm, class A, Fig 4.1). If the
fault still remains, replace D600 (class B, Fig 4.4). If that doesn´t help, send the
phone to next repair level
4.8 Signal treatment fault.
Open the phone and check for liquid damages. Power up the board. Check VDIG
and VDSP (both should be 3.2V, Fig 4.6). If one of the values are incorrect then pro-
ceed to chapter 3 ("Doesn´t start"-fault). Check VDSPC (should be 2,5V, Fig 4.2). If
4-00021-2/FEA 209 544/5.C
I888, Standard Electrical Repairs
MUTE
PORTHF
EXTAUD
Fig 4.5
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