Bluetooth Card Intermittent Connection Problem

[poshgeordie]

I'm writing this following a problem with forum member fje's (Javier) T42. He's sent it to me for an unrelated repair and when returned, he found that bluetooth operation was intermittent.

I'm quoting from his post here:

I started to get error messages like "Problem with USB device..." or "unrecognized USB device..." related to the internal Bluetooth device (I was not aware it is an internal USB device in this laptop).

Long story short....Javier found that when he slightly loosened the two screws securing the card to the little pillars on the motherboard, bluetooth worked again. Tighten up the screws and it stops working.
As he says the screws needed to be loosened Quote a micra (yes, not a milimeter, a micra...)!

The following have been checked and are OK:

• BT aerial plug is pushed into the BT card connector. I believe by inference the connection between the aerial wire and the connector is OK but this needs to be 100% confirmed.

• The little white power connector is properly in place on the end of the card, and the other two fitted OK on the motherboard.

• The little metal insulated plate between the bottom of the card and the motherboard pillars is fitted properly.
  I tested the TP with PC Doctor and it was OK.

Leading up to this he found that lifting the card by one edge caused BT to work again.

Conclusions:

• Bad solder joint on the BT card.

• A pin on the multi-way connector motherboard, or the mating part on the BTcard, has a broken solder joint (rather like the well documented T30 memory slot issue).

• Possible short circuit between the BT card and ground around the metal pillar / insulated metal plate area.

It's not possible to be 100% certain what the actual problem is (Javier is understandably unwilling to trust his T42 to the tender mercies of the Euro postal system for this fault!), but it would be useful to see if anyone else has a similar BT problem.

Also I've read through a lot of recent related posts and am wondering if they are in fact suffering from a similar problem to Javier's, with maybe a similar solution.

[fje]

Hi, this "the Javier" Nick referred to in the previous post.

I don't feel to be able to explain better than Nick did what the BT problem has been. Both his points are the ones that we went thru and my english is much poor.

The real situation is that since I very slightly unscrewed the two screws (3 days ago) the problem didn't arise and the laptop was moved from a place to other several times (this is the advantage of laptops and they are intended for it, of course).

I cannot decide which of the 3 possible source of the problem that Nick proposes could be the real one, because all of them could be. The less probable from my humble point of view is a problem with the connector, because if the screws are very thight the fact of slightly liftin the corner of the card where the white modem connector is would have almost no influence on the card connector that is in the opposite side.

On the other hand, having the card a "white plastic envelop", I cannot see which contact could it have with the MB or the screws pillars...

Is there any "in depth" technical friend that could help our community with any similar problem experience or more valuable opinion of what the problem could be ?

Kind regards

Javier

[Harryc]

You'll never know if it's the card or the connector/mounting unless you try another B/T card.