Date: Tue, 8 Oct 2019 18:58:45 +0000
Reply-To: Richard Koerner <rjkinpb@SBCGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Richard Koerner <rjkinpb@SBCGLOBAL.NET>
Subject: Re: Replaced instrument circuit foil
In-Reply-To: <CAAtTkO9oaz56LRiqqOkEjZHO_bCwQu25z3o8iYbzChanvXhvyw@mail.gmail.com>
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It's been about 15 years so my recollection of the details is hazy, but I fixed wonky performance in my Vanagon LCD clock by simply cleaning all the contact surfaces. Used a Q-tip cotton swab and rubbing alcohol. Clean the glass LCD where the zebra strips contact, the rubber zebra strips themselves, and the PCB contact area. I can't remember about the hour and minute switches....whether a silicon pad with a conductive rubber puck is used or not...but of course they need to be clean too. Yes, orientation of the glass is important; there is at least one YouTube video which shows correct orientation. Also, I would guess the Jetta/Golf clock of same era should be fine.....engineers like to use common parts if possible. Anyway, it was a fun and satisfying job.
The issue is that due to sun exposure and resultant heat, the oily plasticizer molecules are driven out of surrounding ABS plastic, where it subsequently deposits itself onto the glass and nearby surfaces, and then by capillary action on a microscopic level works it's way between contact surfaces. Technical term is "plasticizer migration". At least this is my theory anyway. (Note: this is why newer cars get a film of "something" on the interior glass; over time, this phenomenon lessens, and glass is cleaner....but plastic parts are more brittle as we all know.) The wonderful "new car smell" is plasticizer molecules.
BTW....I just 2 days ago used this same cleaning method to fix an increasingly stubborn TV remote control. Unsnapped/unscrewed the plastic body; gently cleaned the conductive carbon traces on PCB and also the conductive rubber pucks on the underside of the silicone buttons. Good as new.
Warning: since it's been so long, and I don't feel like tearing apart my cluster to review the specifics, some of the above-mentioned details may not be totally accurate. But I don't think you'll hurt anything by cleaning as described.
Rich
San Diego
On Tuesday, October 8, 2019, 9:14:08 AM PDT, Richard Koller <brvkoller@GMAIL.COM> wrote:
Hi Vanagoneers,
Thanks for the great advice on replacing the old circuit foil. I ended up
using the Gowesty circuit boards and all works fine except the digital
clock is wonky. In the process I replaced the old LCD clock screen with a
salvage from a golf or jetta. The LCD receives power and displays some
numerals but it isn't normal and can't be adjusted with the two buttons at
the sides. It looks identical to the vanagon version so I'm stumped as to
why it refuses to cooperate. Is it possible to install this LCD upside
down?
Thanks
Rick Koller
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