Thinkpad AC adapter repair

Same weeks ago the AC adapter of my Thinkpad (R51, buyed in 2004) began to fail. In the beginning was a simple, annyoning failure that was solved moving the adapter. But as it usually happens, the real collapse came when I need desperately to use my laptop.

I go the first ideas to repair the adapter from a message by David Ross in the Thinkpad mailing list at MIT. You can read in the thread what I suspected some time before: this was a problem of bad design of the adapter, maybe deliberately, in order to force you to buy a new adapter. The wire breaks always in the joint with the adapter, and when you try to open it to replace the wire, you find no screw: the case is hardly glued.

So I decided to take photos of the repairment and I hanged them in my gallery. I was lucky and I began to open with a screwdriver on the perfect point to not damage the circuits. Then I went on opening with a dull knife. I marked the points and movements on the photos.

I cutt of the damaged wire and replaced it. I welded against the piece of wire that was directly welded to the circuit board (I left this piece of wire to avoid welding directly in the board). Finally I read in HardLimit forums the epoxy glue I use (Ceys Araldit) insulates at least 25000 V so I used it to ensure the two wires don’t make contact again. Then I glued the case again with epoxy too.

The adapter runs perfectly again. I hope my advice and photos can help somebody with the same problem.

Of course I performed an autopsy on the damaged wire. I found the central wire broke its wrapper and made contact with the external wire, that was partially broken because fatigue too. I was lucky the shortcircuit didn’t damage the laptop.