Ericsson R250s PRO Troubleshooting Instructions page 10

3.3 The phone runs as long as the On/Off key is pressed
Disassemble the phone and check for liquid damage.
No further action should be taken for a liquid damaged telephone.
Make sure the system connector pads-J602 not are damaged or burned.
Mount the board in the fixture. Start it up and keep it running by keeping DCIO high.
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Measure the voltage at C692 >3V.
3.4 The phone consumes more than 200 mA
Disassemble the phone and check for liquid damage.
No further action should be taken for a liquid damaged telephone.
Make sure the system connector pads not are damaged or burned.
Mount the board in the fixture. Start it up and keep it running by keeping DCIO high.
•
Check the current consumption again.
•
Check the resistance from VBATT to ground >1 Mohms.
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Check VDIG on N702 pin5 and VDSP-N701 pin5 voltage ~3.2V.
4/00021-2/FEA 209 544/18 D
If it is correct, check the soldering at D600 pin 119, measure the resistance of C692
>200 kohms
If the resistance is incorrect replace the capacitor.
If the resistance is correct, measure the input voltage at N706 pin 2 (VBATT),
and the output voltage at pin 3 ~3.5V. Make sure that there is ground at N706
pin 1.
If VBATT or ground is missing there is a foil damage, send the unit on
according to the local company directives.
If VBATT and ground are correct but not the output voltage, replace
N706.
If they are all correct, measure the voltage at the positive side of the
backup capacitor, C720 ~3.2V.
If it is more than 200mA, replace the display and the elastomer and try again.
If it is less, send the unit on according to the local company directives
If it is incorrect, measure the resistance of R720 ~180 kohms,
and R719 ~47kohms.
If they are correct, replace V711.
If the voltage is correct, measure the resistance from the
positive side of C720 to C692 ~0 ohms.
If it is incorrect then there is a foil damage, send the unit on
according to the local company directives.
Standard Trouble Shooting Instructions
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