Motorola C115, C116, C117 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: LVCCFSB2004-231 (Rev. A)
Author: Rajesh Verma
Date: November 15, 2004
Total No. of Pages: 3
Subject: GSM C115 – Display Missing Line or Pixels
Model Affected: GSM C115/116/117
Level of Repair: 2

Problem:
Service is aware of an issue identified during the 1st 200 NPI Analysis on C115.
Some units, returned with a customer complaint of “Corrupt Display”. Customer
may notice one or more lines of pixels missing horizontally across the LCD. This
is caused by failures of the Giantplus LCD display modules part number
763000C002W either due to scratches on the ITO lines or display IC’s solder ball
height. The ITO line scratches are caused by either defective raw material or
scratches caused by the line operator during electrical probing. The display IC’s
solder ball height non-uniformity is caused by solder flow process. The figures
below show an example of a display with a missing line or pixels.

Fig. 1.0 – Display Missing Line Fig. 2.0 – Display Missing Line

Solution:

Corrective actions were implemented by supplier Giantplus from Oct.1, 2004.
Giantplus have introduced the following improvements to their process:

1. Inspect incoming ITO Glass (raw material) under Microscope has been
started since week 40, 2004 (starting Oct.4).

2. Giantplus will measure the resistance of the panel’s to check for opens or
shorts on the ITO traces.

MOTOROLA INTERNAL USE ONLY Page 1

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

Website: gs.mot.com

3. Probing may cause a micro scratch. To prevent this from happening,
supplier have introduced following actions:

a. Needle Cleaning has been changed from once/lot to twice/lot
b. Calibration time has been changed from two weeks to once per

week.

c. WIP sample inspection introduced every 120pcs/lot

4. For display IC solder ball height non-uniformity, additional inspection
processes were implemented to capture any further defects:

a. Giantplus started inspecting material from Sept 10, 2004 under

microscope for solder uniformity.

b. Sitronix (IC supplier for Giantplus) to verify IC solder ball height,

starting from week 40, 2004 (starting Oct.4).

Service Action
Customer Returns:

When servicing affected GSM C115 customer returns with a customer complaint
of “Corrupt Display- Missing Line”, then:

1. Power up the phone and observe the display for missing line or pixels.

a. If the unit does not display these symptoms, then proceed with a

normal troubleshooting techniques as per the customer complaint.

2. Remove the display from the main PCB and verify that the failure is
caused by the display module itself by replacing the suspect module with
a known good module.

3. Finally, replace the defective display module with a module date code
after wk41 of 2004 (starting Oct.11).

If the unit still displays the original failure symptoms with the known good module,
then troubleshoot the PCB for defects.

MOTOROLA INTERNAL USE ONLY Page 2