How to permanently fix Seiko G757 faded/fading/incomplete screen problem - Seiko & Citizen Watch Forum – Japanese Watch Reviews, Discussion & Trading
Reply
 
LinkBack Thread Tools
Old 03-20-2017, 09:39 AM   #1 (permalink)
Junior Member
 
Join Date: Mar 2017
Location: Roy NM
Posts: 5
Points: 0 (+)
Default How to permanently fix Seiko G757 faded/fading/incomplete screen problem

As many G757 owners have discovered, the Seiko G757 tends to lose contrast in the screen over the years until the screen becomes unreadable. You can find many G757s on ebay that have this problem, and they're typically much cheaper than a completely working one. I've seen many different suggestions for how to fix this problem, ranging from disassembling the watch and leaving the PCB in your oven for a half hour, to dropping it in a bath of various cleaning chemicals. After several unsuccessful attempts to restore my G757s, I have finally found a way that addresses the root problem with the G757.

I noticed that on all of mine, the contrast got progressively worse every fifteen seconds, whenever another quarter of the second display was filled. This problem wasn't present when the watch was left in dual time mode, or another mode where the second display wasn't filling completely.

On the G757's PCB, there is a row of four rectangular SMD capacitors labeled "Upconverter Condenser" on the G757 service manual/parts list. These wear out after a few decades and must be replaced.

These capacitors should be 170 or 180 nanofarads, but some of mine were as low as 130.

To repair the watch, you'll need four 180 nanofarad capacitors.


What you need:

Soldering Iron
Helping Hands (Stand with magnifying glass and alligator clips for holding what you solder)
Tweezers
4x 180 SMD nanofarad ceramic capacitors. Metric 2012 size are slightly smaller than the original, but they should fit.
Thin screwdriver or solder scraper for unscrewing the PCB from the case
Magnet for holding screws THIS IS IMPORTANT

Optional:
Solder wick. These capacitors are small enough that laying a wedge tipped soldering iron over the top was enough to desolder both ends, but a solder wick would have probably made it easier.


Repairing the watch is pretty simple. Start by opening the outer case and taking out the PCB + inner case assembly. There's a metal clip with four edges holding on the screen, the mirror, and the plastic spacer. This can be removed by prying open the four clips attached to the green case.

The LCD interfaces with the PCB through two rubber strips that are commonly referred to as "Zebra stripes." These can safely be detached from the screen and interchanged with each other. The zebra stripes do have an up side and a down side. If you take a close look at them, you should see one side that appears to have a few thicker lines between the normal lines. This is the side that should be touching the PCB when the watch is reassembled.

With the case and LCD removed, carefully unscrew the PCB from the green case. If there's any corrosion or battery residue on it, the PCB can be cleaned with rubbing alcohol and a Q-tip, or in a rubbing alcohol bath.

With the capacitor side up, place the PCB in your helping hands.

Desolder the four capacitors and replace them with the new ones.

Now, you can reassemble the watch and it should have its contrast completely restored. This should work for all models of the G757.


UPDATE:
When I first made this repair, I used old capacitors from different G757s. These failed after two months when I fell asleep on them and they overheated. I replaced them with brand new capacitors, which has significantly decreased the power consumption of the watch. Originally, it would burn through batteries in a bit over 3 weeks from brand new to low contrast. Two months later, I'm still on the first battery I used after replacing the capacitor, and there's no noticeable contrast loss or any other indication of a dying battery.

Last edited by Dongs; 08-06-2017 at 03:51 PM. Reason: More info
Dongs is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 03-20-2017, 02:04 PM   #2 (permalink)
Junior Member
 
Join Date: Mar 2017
Location: Roy NM
Posts: 5
Points: 0 (+)
Default

Answered my own question, trimming capacitors are around 3 nanofarads or 3 microfarads, I forget which.

Last edited by Dongs; 08-06-2017 at 03:44 PM. Reason: I figured it out myself
Dongs is offline   Reply With Quote Quick reply to this message
Old 08-03-2017, 09:53 AM   #3 (permalink)
Junior Member
 
Join Date: Aug 2017
Posts: 1
Points: 0 (+)
Default Help with my G757?

I picked up a beautiful old Seiko G757 405a with a Sterling silver and turquoise band at a rummage sale. I did a cleaning and tried replacing battery. No luck. Anyone want to try the dead screen repair mentioned in the forums?

I'm currently on contract in NYC (through end of August) and brought the watch with me hoping to find a local tinkerer or expert. I live full time in Seattle though and would be willing to meet someone up there as well.

Anyone wanna help a brother out? (Paid to do it obviously

Thanks!
Brandononeill is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 08-03-2017, 12:46 PM   #4 (permalink)
Senior Member
 
melt's Avatar
 
Join Date: Apr 2010
Posts: 1,767
Points: 21 (+)
Default

Hey Brandononeill look here. This is what I did. I'm in the UK though. Worth a try.

https://www.thewatchsite.com/34-watch...-g757-fix.html
melt is offline   Reply With Quote Quick reply to this message
Old 08-06-2017, 03:42 PM   #5 (permalink)
Junior Member
 
Join Date: Mar 2017
Location: Roy NM
Posts: 5
Points: 0 (+)
Default

Mind posting some pictures of the PCB? I'm on the east coast, so if you're willing to drive to Massachusetts or mail it to me, I could try fixing it. I wouldn't be able to get to it until the 16th or slightly later though.

Melt, I tried that with one of mine, and it didn't work. Usually dropping the PCB in the oven will fix bad solder joints, or temporarily fix electromigration, which wasn't the problem with mine.

Last edited by Dongs; 08-07-2017 at 08:39 AM.
Dongs is offline   Reply With Quote Quick reply to this message
Reply

Tags
broken, contrast, faded, g757, screen

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Seiko & Citizen Watch Forum – Japanese Watch Reviews, Discussion & Trading forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in


Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
An Incomplete History of Seiko 6217-8000/8001 Prices RossR THE JAPANESE WATCH DISCUSSION FORUM 25 06-24-2017 06:02 PM
7T32 - how to fix or what is the problem? anzac1957 THE JAPANESE WATCH DISCUSSION FORUM 2 09-25-2011 12:14 AM
WTB: Seiko 6105B movement, could be incomplete or non working samgher SEIKO & CITIZEN TRADING POST 0 03-30-2011 02:07 PM
Vintage seiko dial color variations - fading or factory? Spencer PK THE JAPANESE WATCH DISCUSSION FORUM 8 10-26-2010 02:01 AM
Strange case fading… bender57x THE JAPANESE WATCH DISCUSSION FORUM 2 07-21-2010 07:08 AM


All times are GMT -4. The time now is 04:22 AM.



Powered by vBulletin® Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.