Game Gear fix when it ISN'T a capacitor problem.

Hey.
So up to a couple of years ago fixing a Sega Game Gear was easy for me, getting some new caps, replacing them and the console was as good as new...
...But lately, it seems more and more of them are unfix-able by this, they seem to suffer from an issue where they turn on and off after 0-2 seconds, no matter what capacitors you replace.

I've been reading on this, there are MANY threads where this questions was asked, the answers are inconsistent and are pretty much a "thrown out there" theories. To my understanding NO ONE knows why this happens, some say it is the gunk on the board, some say it is the LCD drawing too much power but none of the countermeasures for this seem to fix the issue.

So, my questions are:
1. Did you experience this too? Did you also notice this happening more and more frequently?
2. Did you manager to fix this in a way that works for most if not all units?

Thank you all.
Ben.

 

I had already game gears where traces got damaged from the leaking caps. but was no prob to bridge them.
The LCD by itself isnt drawing much power, its the old background phosphor light. its possible that they die too, but hadnt such a case.
maybe worth a try to desolder the light and see if it turns on then (shine a flashlight to the screen to see if something happens).

If this may be the case, you can replace it with LEDs and have a game gear with around 20hours runtime on a battery set .

 

Mine died in the Nineties. The machine kept on playing... you just couldn't see anything.

It's a patchy bodge at best.

 

Some people seem to get "all capacitors" and "all electrolytic capacitors" confused. Places like Console5 sell replacement kits for all of the larger electrolytic capacitors, but these kits do not include replacement ceramic surface mount caps for the smaller values. However, these consoles are old enough where even these typically more stable ceramic capacitors can fail.

TL;DR - If you didn't replace any tiny surface mount caps, you didn't replace all of the caps.

 

There are multiple reasons that the unit will quickly power off like that (as you have probably seen with your research). Even low batteries will boot the blue sega screen for a few seconds and then shut off the system.

The gunk on your board that you mentioned others talked about was most likely the electrolytic fluid from the failed caps.

Are you currently working on a board that has issues, or are you just doing research?

 

No. You don't need to replace ceramics. Just electrolytics.

You don't need to replace SMT caps.

 

I'm well aware that this is the conventional wisdom. However, it has not been my experience lately. Just a few weeks ago I fixed a SNES with wacky discolored video output by swapping out the SMD caps on the RGB lines. SMD ceramic caps can (and do!) go bad just like any other cap, however, they seem to have a much much longer life than electrolytics...thus the conventional wisdom.

The point I'm trying to make is that things like SMD caps are starting to go bad on consoles of this era. This is purely anecdotal evidence, but that's exactly what the OP is asking for.

 

Replacing the power board has fixed about 75% of these, I used to buy bulk game gears for repair and resale, some units though would blow the replacement board after a few minutes. My guess has been issues with the inverter. Given the high voltage I would suspect a safety circuit or a transformer problem. Most of these had signs of corrosion on the reflector or the backlight was slightly slow to start.

 

Well, I have such example lying on my desk. It's 1 ASIC GG in great condition, no leaks, gunk, etc. I replaced all electrolytic caps, also tried different power boards. Finally removed background light since I was going to backlight mod it anyway. No result. It's a waste since it looks inside like new. I'd agree with TriState294 that some SMD part(s), probably capacitor(s) need replacement, but this takes some skills...

 

Well, I can't say I've seen this issue a lot though I have repaired a few (maybe 20?) GG's over the years.

First, you should isolate your issue. The GG power supply board only outputs (in the vast majority of models) +5vdc and +34vdc. The DC-DC converter it uses is well documented with schematics online and the GG service manuals of course, which you can find on sega-16 and everywhere else.

The GG should boot (i..e power light) with only +5vdc since that is all the ASICS, RAM, Z80, etc require. They are likely shutting off because of the GGs (freaking amazing) watchdog circuitry.

SMD caps can go bad, sure, but it is pretty darn rare. In any case, you can wire in +5v from a bunch supply (don't trust your 20+ year old power board) and see what happens. Check around for corrosion, and replace the SMD bypass caps if you like. Though I find when these go bad they often are a direct short.

-Segasonicfan

 

People swap the capacitors without cleaning the boards properly. The goo stays there corroding the board. Once it finishes corroding the trace is cut and current no longer flows.

A couple of years ago I had a 1st gen Game Gear (no TMSS) unit sit on my "parts bin" for almost half a year with that fault until I had the bright idea of looking it's circuit board with a strong light, through the board, which allowed me to see the severed trace. Once I mended the trace, it stopped shutting down instantly after powered on.

It is still working to this day.

 

When recapping any GG I always remove the caps with my soldering iron and tweezers. Scrub the living shit out of the board. If it's bad enough - I'll give the system an "Acehol" bath (92% Isopropanol, 8% Acetone - NEVER go above 8% acetone. You'll literally dissolve the soldermask... like acid...)


I have experienced this problem before. It can be a couple things in my experience. One - bad traces. The electrolytic fluid in all capacitors is highly corrosive. It's likely these caps started to leak just a few years after a specific Game Gear's manufacture date; I.E - these caps have had a lot of time, to do a lot of damage.

Two - Bad A/C adapter, or dead batteries. Seems trivial to even mention, I know. But you wouldn't believe the amount of people who believe systems are dead when in reality it's just a faulty AC adapter.

Three - Bad power board. This can usually stem from a couple of problems. Trace corrosion can easily be the cause of a faulty power board. However, incorrect polarity on the AC adapter can also cause this plus a myriad of other AC adapter issues.

I recommend testing the system with a new power board. Make sure that you replace the caps on the power board in addition to the rest of the caps on the boards.

And just a friendly reminder - always make sure you're wearing your wristsrap

I've been playing around with the DSLite (DSi) screen backlight. Works worlds better than a bunch of LED's. Only issue is the fact that you need a stepup converter to step 5VDC to 12.