Quick answer: dead vertical lines on an original Game Boy (DMG-01) screen are usually caused by the LCD’s ribbon cable coming loose from the glass. The bond is made with heat-activated adhesive, so carefully reheating it with a temperature-controlled soldering iron while pressing gently often reconnects the lines. Start low (around 220°C / 430°F), keep the tip moving and never hold it in one place for more than 2–3 seconds. If the lines will not come back, an LCD or IPS screen replacement is the permanent fix.
Lines on the screen are among the most common faults on the original grey Game Boy, and the reason many otherwise healthy consoles are sold cheaply as “faulty”. This guide explains why it happens, how to fix it and what to do if the heat method does not work.
A word of caution: this repair uses heat on a part that cannot be replaced like for like. Too much heat or pressure can make lines worse or damage the screen. Practise patience, start cool and work up slowly.
Why Game Boy screens get vertical lines
The original Game Boy’s LCD connects to the circuit board through thin flexible ribbon cables. Where those ribbons meet the glass, they are bonded with a heat-set conductive adhesive rather than solder. Over decades, heat, knocks and age weaken that bond. When individual traces lose contact, the matching rows or columns of pixels stop working.
- Vertical lines (dead columns) come from the ribbon along the top edge of the screen. These are the most common and the easiest to fix.
- Horizontal lines (dead rows) come from the ribbon along the side of the screen. They are harder and riskier to fix because of a plastic layer near the bond, so they need lower temperatures.
The fault is mainly a DMG problem. Game Boy Pocket and Color screens use a different construction, and lines on those are usually better solved with a screen swap.
Diagnose the problem first
Before opening the console, check that you are dealing with a ribbon fault and not something else:
- Straight lines that stay put whatever is on screen, and that are blank or stuck dark, point to the ribbon bond. That is the fault this guide fixes.
- Lines that change with pressure: gently press on the front of the case above the screen. If lines flicker on and off, the bond is loose and the heat fix has a good chance of working.
- A faded or blank screen with no lines is often just the contrast wheel, or a dirty contrast control. Try turning it fully both ways first.
- Dark blotches or “screen rot” spreading from the edges is a different fault in the LCD itself, which heat will not fix. That needs a replacement screen.
- Garbled graphics or a scrambled logo usually means a dirty cartridge or cartridge slot, not the screen. Clean the cartridge contacts first.
Write down or photograph which lines are dead before you start. It makes it easier to see progress and to spot if a pass made anything worse.
What you need
- A tri-wing screwdriver for the back case screws, plus a small Phillips screwdriver.
- A temperature-controlled soldering iron with a wide flat or chisel tip. A cheap iron without temperature control is risky here. See our guide to the best cheap soldering irons if you need one.
- Kapton tape (optional) to protect the glass edge.
- Isopropyl alcohol and cotton swabs to clean off residue.
Useful kits: tri-wing screwdriver and temperature-controlled soldering iron (check price and reviews).
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Step-by-step: fixing vertical lines
- Remove the batteries and unscrew the tri-wing screws on the back, including the ones inside the battery compartment.
- Open the case carefully. The front and back halves are joined by a ribbon cable. Separate them gently so you do not tear it.
- Expose the top ribbon bond. Peel back the rubber strip or tape covering the top edge of the screen, where the ribbon meets the glass.
- Power the console on with a game in it and turn the contrast up. This lets you see the lines disappear as you work. Make sure no metal touches the board.
- Set the iron to around 220°C (430°F). Lay the flat of the tip across the ribbon bond near the dead lines, with light, even pressure.
- Keep moving. Slide slowly along the bond for no more than 2–3 seconds at a time, then lift off.
- Press while it cools. Hold gentle pressure on the area with a finger or a flat, non-metallic tool for a few seconds as the adhesive sets.
- Check and repeat. If the lines remain, raise the temperature in small steps. Many repairers go up to around 280–300°C, but go slowly and stop if you see any discolouration.
- Rest and recheck. Let the console cool, then test again later. Some lines come back after a few passes; others reappear after a day and need another session.
- Reassemble and refit the rubber strip or tape over the bond.
Tips for a better result
- Do several short passes rather than one long one. Heat builds up quickly in the glass.
- Work on the side with the dead lines, not the full length of the bond.
- Cover the glass next to the bond with Kapton tape if your tip is wide.
- Do not press hard. Too much pressure can crack the glass or push the adhesive out.
- Try lower first on horizontal lines. Guides commonly recommend about 150–200°C or lower, because of the plastic layer near the side ribbon.
Common mistakes to avoid
- Using a fixed-temperature iron. Many basic irons run far hotter than this repair needs. Without temperature control, it is easy to burn the ribbon in a single touch.
- Holding the tip still. Dwelling on one spot concentrates heat and can lift or burn the ribbon. Keep moving, and use short contacts.
- Starting too hot. You can always add heat, but you cannot undo a burnt bond. Start at the low end and step up.
- Heating the side ribbon like the top one. The horizontal-lines ribbon needs much less heat. Treat it as a separate, more delicate job.
- Forcing the case open. The ribbon between the two halves of the case is fragile. A torn ribbon is a much bigger repair than a few dead lines.
- Giving up after one pass. Several short sessions often succeed where one long attempt fails.
When the heat fix does not work
Some lines are permanent, especially where the ribbon has been damaged or previously overheated. Your options then are:
- Replace the LCD with a donor DMG screen. You will need to transfer the polarizer and glass lens.
- Fit an IPS or backlit screen kit. These replace the original LCD entirely, end the lines problem for good and add a backlight. They change the look of the console, so purists may prefer to stick with the original screen. Our guide to the best Game Boy mods and screen replacements compares the options.
Is a Game Boy with lines worth fixing?
Usually, yes. A DMG with lines is often sold cheaply, and even if the heat repair fails, a screen kit makes it a better console than it was new. Check our original Game Boy price guide for typical values before buying or selling.
While the console is open, it is a good time for other maintenance. See our guide to restoring retro handhelds for cleaning the case and buttons, and how to replace Game Boy cartridge save batteries if your games have stopped saving.
If the speaker is quiet or silent while the case is open, our Game Boy no sound fix covers the headphone-jack switch, volume wheel and audio capacitors.
FAQ
What causes vertical lines on a Game Boy screen?
The LCD’s ribbon cable loses contact with the glass. The connection is a heat-set adhesive bond rather than solder, and it weakens with age, heat and knocks.
Can you fix Game Boy vertical lines?
Often, yes. Carefully reheating the ribbon bond along the top of the screen with a temperature-controlled soldering iron, while pressing gently, reconnects the lines in many cases.
What temperature should I use to fix Game Boy lines?
Start low, around 220°C (430°F), and increase slowly if needed. Many repairers go up to around 280–300°C for vertical lines. Horizontal lines need lower temperatures, about 150–200°C or less.
Do the lines come back after fixing?
Sometimes. A repair can last years or fail again within days. Repeating the process usually helps; if not, a replacement screen is the permanent fix.
Are horizontal lines harder to fix than vertical lines?
Yes. The side ribbon that controls horizontal lines sits near a plastic layer that is easily damaged by heat, so it needs lower temperatures and more care.
Should I replace the screen instead?
If the heat fix does not work, or you want a backlight, an IPS or backlit screen kit is a reliable option. It changes the original look, so try the heat repair first if you want to keep it stock.