SYMPTOM PROBABLE CAUSE VERIFICATION AND REMEDY of 59 GSM Field Service Support 44 P7689 / P7789 and re-assemble the unit with the new PCB. 5. Personal telephone transmit audio is weak, (usually indicated by called parties complaining of difficulty in hearing voice from personal phone). a) Microphone connections to The main RF / Logic board are defective. Gain access to the Microphone as described in the DISASSEMBLY instructions in this manual. . Check connections. If connector is faulty proceed to c if the connector is OK, proceed to b. b) Microphone defective Gain access to microphone. Disconnect and substitute a known good Microphone. Place a call and verify as heard by called party.
If good, re- assemble portable with new Microphone. If Microphone is not at fault, re-install original Microphone and proceed to c. c) Logic/RF Board Assembly defective. Replace Logic/RF Board Assembly (refer to symptom 1c). Verify that the fault has been cleared and re-assemble the unit with the new PCB. 6. Personal telephone receive audio is weak and/or distorted. (From speaker) a) Connections to/from speaker and Logic/RF Circuit board defective. Gain access to Logic/RF board as described in the DISASSEMBLY instructions in this manual. Check pads on the Logic/RF circuit board. Clean pads if necessary. If pad is at fault proceed to d. If connection is not at fault, Proceed to b.
b) Earpiece Speaker defective. Remove speaker from front housing and insert known good speaker. Place a call and verify improvement in earpiece audio. If better, reassemble the phone with the good speaker. If it was no better then proceed to c. c) Antenna assembly is defective. Attempt a re-phasing of the unit and recheck the symptom. If symptom is the same but unit re-phases correctly, check to make sure the antenna connector is correctly soldered to the main board and that the antenna is fitted correctly. If ok, substitute a known good antenna assembly. If this does not cure the fault, re-install the original assembly then proceed to d. d) Logic/RF Board Assembly Defective.
d) Replace Logic/RF Assembly (refer to symptom 1c). Verify that the fault has been cleared and Re-assemble the unit with the new PCB. 7. Personal telephone will not recognize/accept SIM card a) SIM card defective Initially check that the contacts on the card are not dirty. Clean if necessary, and check if fault has been eliminated. If the contacts are clean, insert a Known good SIM card into the portable telephone. Power up the unit and confirm whether or not the card has been accepted. If the fault no longer Exists, the defective SIM card should be replaced. If the SIM card is not at fault, proceed to b. b) Logic/RF Board Assembly Defective.
Replace Logic/RF Board Assembly (refer to symptom 1c). Verify that the fault has been cleared and re-assemble the unit with the new PCB. 8. Phone does not sense when flip is Opened or closed (L7789 Only) (usually indicated by inability to answer incoming calls by opening the flip, or inability to make outgoing calls). a) Magnet in flip defective Replace Front / flip assembly with known good one, refer to the DISASSEMBLY instructions in this manual. Place call to portable phone and verify ability to answer by opening flip. If faulty rebuild phone with new front / flip Assy. If fault is still present, replace original front/flip assembly and proceed to b. b) Logic/RF Board Assembly Defective.
Replace Logic/RF Board Assembly (refer to symptom 1c). Verify that the fault has been cleared and re-assemble the unit with the new PCB. 9. Internal Charger not working a) Faulty charger circuit on main Board. Test a selection of batteries in the rear pocket of the desktop charger. Check LED display for the charging indications. If these are charging ok, then the internal charger is at fault. Replace Logic/RF Board Assembly