Retell.IT – 2013 – Faulty capacitor on Toshiba laptop

Speaking about faulty capacitors reminded me of a Toshiba laptop that I repaired in August 2013.  This Toshiba laptop belonged to a friend’s landlord – if my friend could get it fixed economically, he could score brownie points – always an advantage to be on good terms with your landlord, especially when the rental climate looks like rents are rising.

SONY DSC

This is with the laptop taken apart – see the massive amounts of dust in the cpu heatsink heat distributor and fan just above.  The laptop would fail to boot and from research on the internet, the cause was a failed capacitor – the rectangular NEC TOKIN inside that metal plate near the bottom left.  This capacitor was a bugger to remove – I tried Infrared heating – it just started to cook the plastic top and did not budge.  These are often glued down, but because it had a large contact area on the board, it was impossible to remove without more specialized equipment that I don’t have, i.e. dark infrared reworking station with under board heater and good temperature controller.

I had to effective destroy the capacitor piece by piece, layer by layer.  Actually capacitors are fragile and easy to destroy especially if I am wielding a scalpel.  Eventually it was removed, and I replaced it with four smd capacitors.  I had to use a fibreglass pen to remove the green coating from the board in order to do the soldering of the replacement capacitors.

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Now a closeup of the board with the replacement capacitors.  The motherboard was reassembled in the laptop, after cleaning all the dust, of course – then powered on, and it worked.  Total cost to the friend’s landlord was $60 plus a lot of brownie points.

[Note]  I have since learned that I could have used my existing infrared rework station by using the under board heater, then heating the capacitor with the infrared, and use my hot-air rework station to add additional heat – to keep the temperature steady.  But that comes with a risk of damage to the board due to the heat being there for much longer – my scalpel was much better.

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2 thoughts on “Retell.IT – 2013 – Faulty capacitor on Toshiba laptop

  1. George Guga says:

    Hello
    Could you please tell me more about the replacement capacitors? Are they tantalum?
    I’m trying to fix a Dell laptop and it has very similar looking caps; the capacitance is obvious, but I can’t seem to find how to read the code in order to figure out the voltage.
    Below the capacitance, mine say stuff like 208PUd, or 29KOTd or 28N2Xe. Any idea what to make of that?
    Thanks

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    • George, Hi. They are not tantalum which are solid capacitors. Usually that number refers to the capacitor model or batch numbers. Look for a symbol which indicates the manufacturer – they have there own batch coding. Depending on the location of the capacitor – if this is right next to the CPU, then it is most likely a low voltage. I realize that I had not included information on the replacement capacitors that I used, which were Panasonic EEFSX0E331ER – 330uF 2.5V capacitors. For your Dell laptop, the voltage requirement may be different, so try to find the specifications of the capacitor that you are going to replace.

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