Soldering to EEPROM


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I do NOT advise you do this, 2 long needles are much better.

Soldering the 3 wires to the EEPROM

Soldering 3 wires to the EEPROM is NOT your only choice.

You can use clips or sharp probes or even make your own sharp probes for SDA and SCL then use a clip for the GND connection. 

The GND connection can be made using a larger clip to any metal part of the System Board such as the  metal clips holding the RAM, or the shell of the USB connector, or the metal heat sink or fan parts.

The following steps requires excellent soldering skills and the right tools, after reading this section if you feel that if you do not have the skills and the required tools then have someone else do it for you.

You will need;

  1. adequate lighting

  2. a good magnifying glass,

  3. a large clear desk, so that you can separately
    layout the individual modules together with the screws for that module

  4. excellent soldering skills,

  5. a soldering iron with a fine tip, that is in good order
    it may be wise to use a brand new tip

  6. sponge for cleaning the soldering iron tip

  7. small diameter resin cored solder

  8. 0.18mm enamel coated wire or  similar small diameter insulated wire,
    about 2 metres or 6 feet will be ample. 

  9. a good quality small Philips screw driver
    that does fit the screws in your TP without burring the screw heads.

The soldering process

This is the most critical operation, soldering the wires to the eeprom requires a lot of care and some skill, you are soldering 3 very fine diameter wires to very small narrow FRAGILE eeprom pins.

If you know how to solder, and you have tackled surface mounted components before, you can skip this soldering tutorial.

If you are new to soldering, or if you have never tackled something quite this small, then  do read all this.

It is a good idea to practice soldering some of your fine wire to something other than the real eeprom, practice on something else before tackling the eeprom.

That will either give you confidence or it may convince you that for whatever reason you can't do it, it may be you or your equipment and you need someone else to assist you.

Preparing the soldering iron

You should have a soldering iron with a fine tip.

How fine , you might ask.

The end of the tip must be narrow enough so that it does not bridge across 2 pins of the eeprom.

You do need a decent fine tip soldering iron to solder the wires


The red enamel coated wire [supplied with some KeyMakers on request], can be used to make the soldered connections to the EEPROM.

You clean the tip of your soldering iron, of course your soldering should be switched on and at working temperature.

Apply sufficient solder to the soldering iron tip to form a small blob

Place one end of the red wire inside that blob for about TWO OR THREE SECONDS, that will melt the red insulation


Move the red wire out of the solder and inspect the end of the wire, the red insulation should be melted away revealing a clean silvery coloured tinned copper wire end


below is a close-up view of the wire

If the wire isn't nicely tinned, DO IT AGAIN until it is


Sometimes, you will get a lot of melted enamel on the end of the wire and it will look dirty, don't persevere with it, cut that small section off the end and try again.

For each wire end clean the soldering iron tip by wiping it against a wet sponge designed for use with a soldering iron.

Use a FRESH BLOB OF SOLDER, as the blob will quickly fill up with burnt enamel, only use one blob for one wire end.


You will be trying to solder 1 fine wire to 1 eeprom pin without disturbing the adjacent pins on the eeprom.

Some fine tips are rectangular, that's OK, use the narrow edge.

If the tip is pitted or corroded, don't use it, purchase a brand new tip.

Switch the soldering iron ON and allow it to heat up.

Wet your sponge, this is a sponge that is sold to be used to wipe soldering iron tips, if you don't have one an ordinary kitchen sponge that has not been used [brand new] will do, it is better than not using a sponge at all..

Squeeze all the water out of the sponge so that it is moist but not dripping with water.

Apply a fair amount of fine resin core solder to the tip of the soldering iron, have something underneath to collect the extra melted solder that will drip from the tip, let it coat the entire tip with a fine silvery layer.

The resin core cleans the tip and allows the solder to coat the tip evenly.

Wipe the tip on the sponge to take away all the excess solder and burnt resin, so your tip has a nice even coating of solder.

The reason why you do this is to have a fine layer of solder adhered to the tip to easily conduct the heat from the tip to the wire and eeprom pin. 

A tip that is dirty an without a thin coat of solder, will not work well, the heat will not be easily transferred  and you will be tempted to press it hard against the eeprom pin in a futile attempt to make it work, that will damage your eeprom, it may break the pin etc.

Your iron is ready for use.

If your iron is left switched on for a while before use, repeat the process to coat and clean the tip before using it to solder wires to the eeprom.

It is a good idea to repeat the process of cleaning and coating the tip for each individual wire to be soldered as the insulation on the wire may contaminate the tip. 

The pins on the eeprom are very fragile, easily broken, imagine that they are like aluminium foil in strength

You will be soldering 3 wires to 3 eeprom pins.

When soldering the 3 wires to the eeprom you DO NOT USE FORCE, the heat from the iron contacting the wire and the eeprom pin melts the solder, the heat does the work, you must NOT USE FORCE to push pull or move the eeprom pins.

You perform these steps for each of the three wires.

Trim the part of the wire that is "tinned" [the end that is now coated with solder] to a suitable length, the tinned part of the wire should be roughly the length of the eeprom pin.

So this is what you should have at this point, a wire with a bit at the end that is coated with solder, a fine coating, not a huge blob.

A soldering iron tip that is coated with solder and is clean.

An eeprom pin that you are going to solder the wire to.

Note you are not going to apply any MORE SOLDER to solder the wire to the eeprom pin.

If you apply solder to the eeprom, it will most likely flow down between the pins, and make a solder bridge between adjacent eeprom pins, you don't need that drama.

There is sufficient solder on the wire and the eeprom to enable you to solder the two together.

The reason is that the eeprom pin already has a solder coating from when it was originally soldered to the system board when your TP was manufactured. The wire has solder on it. The iron's tip has solder on it, all three have a fine layer of solder barely noticeable except that it looks silvery in colour.

Next you place the tinned end of the wire on top of the eeprom pin, and bring the soldering iron tip to contact the wire and melt the fine coating of solder on the wire, that in turn heats up and melts the solder on the eeprom pin.

No force is required, just contact between the iron, the wire and the eeprom pin.

When you see the solder on the eeprom pin melting [it should only take 2 or 3seconds max], you know it is melting as it changes appearance from dull silvery to  shinny silvery.

Now keep the wire very still and remove the iron from the wire.

Wait for the wire and eeprom pin to cool down slightly, 3 or 4 seconds is required.

Now gently test that the wire is attached to the eeprom pin, pull the wire ever so gently, if it is attached use clear sticky tape to tape down the wire near the EEPROM onto some part of the system board close to the eeprom pin to prevent the wire being accidentally pulled off while re assembling your TP.

Get your magnifying glass and carefully examine the wire joined to the eeprom pin, check that the wire is soldered to the eeprom pin, check that there are no solder bridges between adjacent eeprom pins, check that eeprom pin has not been lifted up in the air.

You will repeat the above for all 3 wires.

If you end up with a lot of solder between adjacent pins, DON'T PANIC, wipe the soldering iron tip, heat the excess solder with the iron tip, some solder will stick to the iron tip, wipe the tip and repeat the process till the excess solder has been removed. 


I make no warranty that any of my information is correct, or safe, or does or does not breach any warranty clause,  or anything else, it is up to you to decide if you will follow all or any of the instructions to recover the Supervisor Password from a TP. It is up to you to decide, I am not responsible for the results or for any consequential or incidental damages whatsoever.

If you have any questions, email Joe at

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