[T3] An old flasher problem I've never been able to figure out

[Jim Adney]

On 11 Nov 2010 at 1:00, Marklist wrote:

> 71 Manual FI
> 
> My signal flasher only works intermittently.  It usually doesn't work at 
> night or the really early morning.  When it does work at night is 
> usually during the summer or Santa Anas.  But there is not a 100% 
> correlation.  I had this problem with a bug when I was a kid.  I've had 
> this problem with another Type 3.  I've changed the flashers several 
> times and the problem persists.
> 
> I'm thinking that is has something to do with ambient moisture, but it 
> is not enough to produce any noticeable condensation.

My guess is that you're on the right track regarding moisture and corrosion.

Most such problems are easily fixed by simply moving each connection. The 
corrosion layer is VERY thin and fragile, so the slightest movement will break 
thru it, and there's no need to clean the whole surface, because ALL the 
conduction takes place at the very small areas where the tabs press hard 
against one another.

The TS current runs thru the 4-Way flasher switch, too, so exercise that switch 
a bit to clean off it's internal contacts.

Wiggle every connection on the fuse box and the connections to the TS switch at 
the base of the steering column. In addition, I find that the contacts at the 
bulbs are the most likely places for corrosion to become a problem. I use a 
dental pick to clean off the contacts (both ground and hot) in the bulb 
sockets. Then I put some heavy grease on those spots to keep moisture away in 
the future. Avoid getting grease on the glass part of the bulb itself, but on 
the contact area of the base is a good idea. Remember that the bayonette pins 
of the base are your ground connection points.

Since you mentioned the Santa Anas, I'm guessing that you live in SoCal where 
it's generally pretty arid. In that case, corrosion at the bulb bases is not as 
likely as it is here in the midwest, so you might want to try that approach 
last.

-- 
Jim Adney
jadney at vwtype3.org
Madison, WI USA