Sim Problems - Ericsson T28S Troubleshooting Manual

7 SIM Problems

7.1 What is SIM-fault
Insert a functional SIM-card and a charged battery into the phone.
If "Wrong card" or "Insert correct card" is displayed on the display when starting the
phone it means that the phone is SIM-locked.
NOTE!
If the fault remains, send the unit on according to the local company directives.
If the phone displays "Phone lock" on the display it means that the customer has locked the
phone with a personal code. It will be unlocked in the reset program. (Available in the Built
Swap process)
If "PIN:" or "Enter PIN:" is displayed, it means that the SIM-card has been locked with a
personal code.
It is only SIM-fault if "Insert card" is displayed.
7.2 Type of fault
Open the phone and check for liquid damage.
Replace J603.
Measure the resistance from pin 1 to pin 5 of J603 (>1 Mohm).
If the resistance is incorrect, replace C734, C736.
Measure the resistance of R734 (10 kohms).
If the resistance is incorrect, replace R734.
Measure the resistance from R733, at the pin close to R731, to pin 1 of J603 (15 kohms).
If the resistance is incorrect, replace R730.
Measure the resistance from R733, the pin close to R731, to pin 7 of J603 (33 ohms).
If the resistance is incorrect, replace R733.
Measure the resistance from R731, at the pin close to R730, to pin 2 of J603 (33 ohms).
If the resistance is incorrect, replace R731.
Measure the resistance from R732, at the pin close to R731, to pin 3 of J603 (0 ohm).
If the resistance is incorrect, replace R732.
Replace C735.
If the fault remains, send the unit on according to the local company directives.
4/00021-2/FEA 209 544/19 E
If the phone shall be SIM-locked, make sure that a correct SIM-card is used.
Trouble Shooting Guide, Standard
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