Motorola Mid-Rate Service Manual

EIF4292

GLOBAL GSM SERVICE SUPPORT FIELD SERVICE BULLETIN

Title: P2K Mid-Rate Charger Incompatibility

Author: Anne McCluskey/ Alan Abraham

Date: 23

Number of Pages: 2

Bulletin Ref. No: EI0403(Rev. B)

Product: V70 and T720

System: GSM

Problem:

A problem has been identified in charger SPN4940C from vendor PhiHong, when used with T720 and V70 products. The issue is exhibited by the unit powering down when a call is made or received, while in low battery condition and during charging. The combination of a new electrical design and the exclusion of a capacitor on ExtB+ line on the radio has resulted in this issue. When the power supply experiences a sudden change in current demand from the phone, the inductance of the power supply cable and the capacitance on the output of the power supply, create a voltage ringing on the ExtB+ line and thus results in a power re-set. When this happens, the phone will default to charge only mode, the phone is not damaged.

Solution: PHIHONG

suffixed from suffix C to D for ALL

January 2003

have implemented a design change to the charger; the charger part number has been up

new chargers with the capacitor fitted.

Part Number – SPN4940D (see fig. 1)

Please note that chargers do not exhibit this issue with GSM products other than V70 and T720.

Fig. 1

MOTOROLA CONFIDENTIAL & PROPRIETARY

EIF4292

T720 & T720i units should also be modified as follows: The resistor at Ref. Des. R7001, should be replaced with a capacitor: part number 2113928R03. (See Fig.

2).

Old : Resistor

Service Action:

All repairs should be logged into EPPRS system as follows:

Customer Complaint: 15 - Phone switched itself off when making or answering a call Root Cause: 54 - Charger Faulty

ew : Capacitor, the body is in Grey

the body is in Black

Fig. 2

MOTOROLA CONFIDENTIAL & PROPRIETARY