Date:         Sun, 14 Dec 2014 03:46:55 -0500
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Re: My Vanagon's blinking coolant light problem vs other
              peoples'---it all blends together
Comments: To: Stuart MacMillan <stuartmacm@GMAIL.COM>
In-Reply-To:  <024c01d0173c$b08e5960$11ab0c20$@gmail.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed

At 08:24 PM 12/13/2014, Stuart MacMillan wrote:
>replacement cap across pads -- light should blink then go out. Put
>it all back together after thoroughly cleaning the circuit board
>with circuit cleaner. While you're in there, replace the LED with a
>brighter one, you'll never have a better chance."

I still recommend it, certainly if you're a bit red-blind like me;
and with red it's actually dimmer, not just confusion about the color
as with green.  I really despise red LED displays in the daytime.

But talk to me if you intend to do it, the circuit is not what I
assume^H^H^H^H^H^Hcalculated (!) at that time.  As built there's a
self-blinking LED (i.e. there's a blinker circuit and  possibly
voltage regulator on a chip that's actually part of the LED.  It's
rated 5V and it's installed in parallel with a 5.1V zener diode.  So
if you replace with a regular LED you'll have to add a
current-limiting resistor AND the LED won't blink.  If it's bright
enough it won't matter.  If you want it to blink you'll need another
self-blinking LED which limits choice and availability.  If it's a
five volt one it's a drop-in replacement; if not you'll either have
to use a different zener or add a resistor or both.  RS used to have
a ?3.5V? one, reasonably brighter, much more orangey; the gauge
original is a very pure red; and slower blink.

<well how was *I* supposed to know they were going to be
tricky?><They're VW, fool, they love tricky.><Um...point taken.>

YOurs,
David