Motorola V400, V500, V505, V525 Service Manual

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Consumer Solutions & Support
US Competency Center
600 North US Highway 45
Libertyville, Illinois 60048

Website: gs.mot.com

FIELD SERVICE BULLETIN

FSB Number: LVCCFSB2005-7
Author: Tony Bryan
Date: January 10, 2005
Total No. of Pages: 3
Subject: Ramless TMR Display (7287946Y01) – White Main Display
Phone Models: GSM Triplets: V400, V500, V505, V525, and V400p
GSM Triplets Refresh: V550, V545
GSM San2rini: V547, V551
Level of Repair: 3

Problem

Service is aware of an issue, identified in recent pre-launch ALT Drop Testing of
the Samsung Ramless TMR Display (7287946Y01). This issue was also
confirmed on some field return units with customer complaints of “Intermittent
White Main Display”. Failure occurs after a drop impact to the side of the flip
while phone is in an active state. Under this circumstance it is possible for the tail
of the display hinge flex to impact, and damage, a discrete (Zero Ohm) resistor
on the display board. This missing resistor will result in a very intermittent white
main display failure. See Fig. 1.0 Below.

Fig. 1.0 – Missing (Zero Ohm) Resistor

Solution

Short-Term: A piece of Kapton Tape (1190142N01) was placed on main display
board over the affected area to protect the discrete components from being
damaged by the flex. See Fig. 2.0 Below
This corrective action has been implemented on all products, using the Samsung
Ramless TMR Display (7287946Y01), built after November 2004.

Note: On some displays you may find a piece of Kapton Tape placed on the far right side of the
display board. This tape is no longer required due to a design chan ge to the metal display frame
completed in January 2004
complete repair.

Long-Term: A redesign of the display flex tail is currently being evaluated by
development to eliminate this failure mode.

MOTOROLA INTERNAL USE ONLY Page 1

LVCCFSB2003-129. This tape can be moved to the affected area to

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Consumer Solutions & Support
US Competency Center
600 North US Highway 45
Libertyville, Illinois 60048

Website: gs.mot.com

Fig. 2.0 - Kapton Tape (1190142N01) Di mensions: 13.0mm x 8.5mm, 0.08mm thick

Field Service Action

Customer Returns:

When servicing affected GSM customer returns, with customer complaints of
“Intermittent White Main Display”, then:

1. Confirm the customer complaint is related to this issue.
a. If the customer complaint is determined not to be related to this

issue, then follow normal troubleshooting techniques per the
customer complaint.

2. Repair the defect by one of the following methods.
a. Replacing the missing resistor utilizing a scrap display, if available.
b. Insert a solder short between the two pads where the resistor

should be. (See Fig. 3.0 Below)

c. Replace the display

3. Reassemble, placing Kapton Tape over affected area, and completely

retest to confirm unit is properly repaired.

Fig. 3.0 –Solder short across pads

When servicing affected GSM customer returns, regardless of customer
complaint, which require the flip to be disassembled, then:

1. Inspect the display module to ensure tape is placed properly over the

affected area.

MOTOROLA INTERNAL USE ONLY Page 2