Ericsson I 888 Trouble-Shooting Instruction page 37

I888, Standard Electrical Repairs
damage (the value is larger than 0 Ohm) the phone has to be discarded. Otherwise
replace D600 (class B).
If the fault still remains, send the phone to the next repair level.
9.5 Red top indicator doesn´t work.
Open the phone and check for liquid damages. Make sure the double LED H650
(class A, Fig 9.4) is correctly soldered.
If the soldering is fine, give the phone power and start it up. Measure the voltage on
H650:2 (Fig 9.4), itshould be 3.8 V. If it is correct, replace H650 (class A). If it is
missing, measure the resistance of R646 (470 Ohm, class A, Fig 9.4). If that resist-
ance is correct, measure the resistance of C621, it should be larger than 10 kOhm, if
it isn´t then replace C621, C614 and C432 (all are class A, Fig 9.4 and 9.5) one by
one and check the resistance after every replace. If the resistances are correct, meas-
ure the voltage on N411:5 (Fig 9.5), it should be 3.8V. If the voltage is incorrect
then replace N411 (class A). If the voltage is correct but not on H650 and the resist-
ance of R646 (Fig 9.4) is correct there is a foil damage and the phone has to be dis-
carded.
Measure the resistance of C655 (class A, Fig 9.4), it should be larger than 1 MOhm,
if not then replace the capacitor. Check the soldering at D600:93 (Fig 9.2). If the
soldering is fine, measure the resistance between D600:93 and H650:1. If there is a
foil damage (the value is larger than 0 Ohm)the phone has to be discarded. Other-
wise replace D600 (class B).
If the fault still remains, send the phone to the next repair level.
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