TL;DR: It seems that the majority of Game Gears that have troubles operating is suffering from leaking electrolytic capacitors, so it makes sense starting with recaping. It is very important to clean the PCB thoroughly of the electrolyte fluid from old capacitors. As GameGear motherboard will operate even with no caps at all, although not recommended.
I bought a Sega Game Gear(VA1 — Twin ASIC (837–7398–01, 837–7719–01, and 837–7996)) at a local flee market. Since it is a European version (different regions have different power plug polarity, so be careful what power supply you use), I used my Spectrum ZX power supply to test it.
Required power supply for European Game Gear: 9V, center negative.
Symptoms: Leaked electrolytic capacitors, turned off after a second.
The first step was a recap (change all of electrolytic capacitors) with a kit I ordered off of Ebay. After each changed capacitor I plugged it to the power brick to see if the symptoms changed. When the C54 and C55 (capacitors responsible for the backlight) have been replaced, the backlight stayed on when powered (this is important later on).
After the full recap of the console, the console stayed on for a second and then turned off (backlight and all); it did not matter if the cartridge was plugged in or not, so this was a step backward.
I measured the voltages on the power board connector and the values were way off or even 0V, so it was time to bring in the big guns.
Expected values on the power board.
I gave the board to my electronic engineer friend and he had some fun with it. He noticed that when measuring the 5V lines all of the voltages collapsed. Then he tried to measure just the 34V line and everything was peachy. This explains the backlight staying on, after changing the C54 and C55, since the 5V line was still broken (from bad capacitors on it (I have not yet changed them all)) and the 34V line was fine. After I replaced all of the capacitors, the issue came back.
So he isolated the issue to the 5V line on the power board, especially on the elements that were shared between the 5V line and the 34V, and reflowing the components fixed the issue.
The powerboard schema.
Things that were reflowed and checked:
1.) L1
2.) C13 (electrolytic cap, usually changed during recap)
3.) C11 (electrolytic cap, usually changed during recap)
4.) C5
So if your Game Gear is experiencing similar symptoms, try measuring the output of the powerboard (first 5V and than 34V lines after power up cycle). It is important that you attach the multimeter before powering on, otherwise you might miss the initial surge. If 34V is stable and the 5V is not, try resoldering the components that are shared between them.
A picture off Facebook from a professional repair man, please note he uses a lot of SMD ceramic/tantalum capacitors (tantalum has the lowest ESR) the size of the caps is 1210/1206. If you find them in the right values, this is a much better option than using electrolytes, because the physical space in the console is very limited and the ceramic/tantalum caps are much more reliable. This board also has the LCD screen mod.
A good guide that it will help you with recaping the electrolytic capacitors.
Recaping the powerboard
I also had problems with solder sticking on the powerboard, this is because of different manufacturing process used on it and a ground plane (Twin ASIC boards are the only ones affected by this, the single ASIC ones are rather easy to desolder). Pull the caps off from the top leaving just the legs. It’s much easier to heat up as there is not a capacitor to dissipate the heat. Also if you cannot or dont have a way to clear the solder, some new solder on the spot and some flux and you can lead one leg at time through and work them down. Or if you have desoldering station that would be the easiest way. Be patient and use higher temperatures if you can, but be careful not to overheat any components.
Power Board Kit
If you’re still not getting the correct voltages a user on Facebook group suggested the Game Gear Power Board IC Repair Kit, which contains the electrolytic capacitors, MB3775 (size SOP 16) IC and 3 power transistors (A, B and C).
It can be found here if you wish to order it: https://retrosix.co.uk/Game-Gear-Power-Board-IC-Repair-Kit-p187708393
Power Board Eagle files
If you would like to make a brand new power board someone made the eagle files (gerber files) available on their website:
Games not loading
Game Gear turns on and off very quickly
If your console turns on and off quickly in general it could be two things:
protection mode of the game gear, which would indicate a short circuit on board
issue with the power board (check above for solution, measure the voltages on the out pins, 5V and 34V lines)
Turning off is a protection mode for Game Gear and something is grounding out (you have a short to the ground (measure resistance between 5v and ground with power switched off)). Can be as simple as a misplaced polarity on a cap, a fleck of solder, bad power board, electrolytic fluid from an old cap, or battery acid under a chip that you can't even see. The base point for troubleshooting would be a nicely and thoroughly cleaned mainboard.
Glowing CFL tube light and no red LED, means that the high voltage circuit works fine and the problem probably lies on the 5V part (but some posts suggest this might not be the case and suggest removing/disabling T1, to confirm this).
At this point you should have recapped board, as most power issues are caused by dried out electrolytic capacitors.
A simple solution would be a IPA bath of the motherboard, as this could help removing any material causing the shorts.
Also, the power monitoring circuitry can be at fault and replacing / reflowing the diode and/or resistors there can help.
Transformer T1 on high voltage leads can also cause problems with startup.
If the fault on your game gear is the CFL tube lights, no power light, black screen then power off. A few times switching on and off and it starts working, than it was suggested to swap tiny transistor next to the 0.47 50v caps, swapping (Q3, Q4 transistors fixed the issue in one case).
Q3 and Q4 transistors (image by: James Brookwell)
Screen flickering
One easy thing to check is leave the Game Gear on, for some time. If your screen is still flickering pay attention to transistors (Q9 and Q10). Sometimes electrolytic fluid from leaked capacitors catches underneath one of the transistors or resistors and that can be causing a slight short.
Additional resources: https://www.reddit.com/r/game_gear/comments/l20nr1/game_gear_lcd_is_rapidly_flickering_after_recap/
Screen issues
There are a couple of common issues with Game Gear screen, however there is no silver bullet for all of the issues.
Personally I would first go with changing all of the electrolytic capacitors and see if that solves the issue.
If the issues still persist, you could try to fix the old screen with couple of tricks described bellow.
The last resolve would be an LCD screen mod McWill or a Chinese clone. (all of the images are from FB group and are here for educational purposes only)
If the lines roll and are not static, than there is usually still hope that recapping will fix the screen issue. With static lines it usually means that there is physical damage to the screen or the driver chip died or is on its way out.
Vertical lines similar to the ones on Game Boy.
Matt Marshall from the Facebook group suggested that sometimes these lines can be removed by (very!) gently warming up the LCD chip & ribbon cable and basically attempt to re-flow the ribbon cable, this should be used as a last result as you may damage the screen. If the lines roll and are not static, than there is usually still hope that recapping will fix the screen issue.
Successful attempt.
Washed out picture is usually a sign of bad electrolytic capacitors.
This Game Gear was also saved with recapping.
Alex Schot from FB group: “The middle IC LCD driver chip is losing connection or failing. Sometimes applying heat to the IC (hover your soldering iron above it for example) and then pressing down will fix the issue.” You could also try with a hairdryer.
This screen was saved by changing electrolytic capacitors. If the lines roll and are not static, than there is usually still hope that recapping will fix the screen issue.
Some have tried to fix this issue by heating the right edge of the GG LCD but have also had it come back not to long after. This issue seem like a typical case off ribbon cable detaching from the screen matrix. As a last resort I would try to heat the connections and try to re-flow them.
A typical example of the vertical controller chip failing or loose connections on the last third. Since the whole third is blank, there is either a complete controller chip failure or it’s not getting any power. This is almost certain beyond repair. But personally I would try to reheat the chip (use hot air at low temperatures) or re-flow the connections. (you can also try to gently squeeze different part of the ribbon to see if there are any changes)
Vertical lines aren’t unfixable so much as its only a temporary fix, they are caused the same way they are on Game boy screens, just heating the ribbon cable with hot air and pressing it down usually removes them however every time the system gets hot you fix melting the connection and it probably dying again.
Another example where heating the ribbon cable helped.
Heat on the connector (yellow exposed metal) above the glass. If the ribbon is cracked, there is not much hope at that point. Except if you’re skilled/desperate enough, you can try to expose the conductive layer on both sides and try to bridge them with a wire/solder blob (something like: https://www.youtube.com/watch?v=qmsFo7uMLCI).
It may also help using the method from Game boy:
Vram issues
VRAM (video RAM) is the chip labelled IC5 and on the back left of the console for 2 ASIC models and when it goes bad the result is seen above. So far the only solution would be to replace it. The chip seems to be Hm65256 blfp-12, Smt pseudostatic Ram 8x32k, but this needs to be confirmed.
Before swapping out the chip, you could try reflowing it, checking for any electrolytic fluid shorting it out (try cleaning it with IPA) and checking for continuity to rule out a broken trace/s.
Modern Sound board replacement:
When you face a shortage of spare parts for our old consoles, the best thing to do is to recreate them from scratch! It’s plug’n’play just like the original.
Modern power board replacement:
A newly designed drop in replacement power board for the GG, that is currently in beta testing. Instead of the barrel plug it has USB-C, so you can power it from a traditional USB power supply, power bank or computer for example.
Developed in house by Luke from RetrosixUK:
Modern shell replacement:
RetrosixUK also offer reproduction of shells in different colors:
LCD screen replacement:
Retrosix:
McWill:
RetroKai:
Chinese clones:
Still need help?
Sometimes this info will not be enough and it’s always good to consult with fellow enthusiasts so you might want to ask for help in a Facebook group:
Resources:
Service manual: https://gamesx.com/wiki/lib/exe/fetch.php?media=schematics:service_manual_-_game_gear_va1.pdf
Recaping guide:
Multiple repair guides and resources: