Ericsson R250s PRO Troubleshooting Instructions page 29

8.5 Alert button malfunction
Disassemble the phone and check for liquid damage, especially around X828 andX829.
No further action should be taken for a liquid damaged telephone.
Make sure that the function of the micro switches in the front cover is ok, if not replace the
faulty switch according to mechanical repair guide.
•
Measure the resistance from the pad X828 to ground >1 Mohm,
8.5.1
•
If the resistance to ground is to low from pad:
If the fault still remains, replace D600.
8.5.2
Check the soldering at D600 pin 120.
•
Measure the resistance from X828 to D600 pin 120 ~0 ohm.
8.6 Speaker phone switch malfunction
Make sure there is no mechanical damage at the switch on the front cover
If there is, the front cover has to be replaced according to mechanical repair guide.
The connection between the switch, mounted on the front cover, and the logic is non-mechanic
based on hall effect.
•
Measure the resistance from the pad X825 to ground >1 Mohm,
8.6.1
•
If the resistance to ground is to low from pad X825 replace C658 and C688.
If the fault still remains, replace D600.
4/00021-2/FEA 209 544/18 D
If it is less, go to.8.4.1
If the resistance is correct, go to 8.4.2
X828: replace C624.
If the resistance is incorrect there is a foil damage, send the unit on according to the
local company directives.
If they are all correct, replace D600.
If it is less, go to 8.5.1
If the resistance is correct, go to 8.5.2
Standard Trouble Shooting Instructions
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