[T3] Turn signal help after Bentley test

[Jacob Adam Schroeder]

I'll also add the following:
When I pull out the emergency flasher switch, all 4 blinkers work as they
should and are at the proper (bright!) brightness level.  This is true
whether the headlights are turned on or off.

Based on this, I think I need to find out what pathway is different between
emergency flash mode (in which all 4 blinkers work as they should whether
headlights are on or off), connecting +49 of the relay to terminal 30 of
the fuse box (in which all 4 blinkers work as they should whether
headlights are on or off), and the normal turn signal pathway (in which the
L side fast blinks all the time, and R side fast blinks when headlights are
on).

One hypothesis is that the emergency switch is bad or the wiring is messed
up there.


The fast blink indicates that the circuit is not drawing the expected
> amount of current. Usually this means a burned out bulb. The
> headlight affecting this indicates that the ground for those lights
> is not good. The ground goes to a screw under the cardboard at the
> front corner of the trunk, next to the front corner of the gas tank.
> Loosen that screw, clean it a bit, put some grease on it to slow down
> future corrosion, and retighten. While you're at it, do this on both
> sides.
>
>
I looked at the grounds in the trunk and they look pretty crummy.  In fact,
I had difficulty loosening either screw.  I will put some penetrating oil
on those to see if I can loosen them without stripping the heads.  But, if
my 4-way emergency blinkers work and the turn signals work when +49 is
connected to 30, wouldn't that indicate that there is no ground problem?

One other reason which makes me think I may have a ground/wiring issue is
that the needle on the fuel gauge "wiggles" slightly when the turn signals
are acting up.  This, of course, does not happen when using the emergency
flashers or when +49 is connected to 30.



> > I performed the test in Bentley (with key off, connecting +49 terminal of
> > emergency flasher to terminal 30 of fuse box and test turn signals) and
> > both left and right work perfectly, at the correct speed, regardless of
> > whether my headlights are on or off.  According to Bentley, this means my
> > switch and relay are OK.
>
> I wasn't familiar with this test, but notice that the next sentence
> in the bentley says to check the switch if the TSs still do not work.
>
>
Indeed, the issue I have is that, when performing this test, everything
works great.  According to Bentley, this means my flasher and relay are
good.  Do the switches ever go bad?



> The test I generally do is to check operation with the 4 way flasher.
> If all the bulbs light equally bright (test at night is best) then
> the bulbs, wiring and relay are okay. That just leaves the TS switch
> as the possible problem. If the headlights affect the test, the front
> grounds are the problem.
>
> If you do my test at night, I think you'll find that the RF TS bulb
> is dim, or maybe it just goes out completely when you turn the
> headlights on (or the R headlight flickers in time with the TS relay,
> and the RF TS bulb flashes out of phase with the RR bulb.)
>
> What's happening is that the headlight filaments are acting as a
> ground pathway for the RF TS bulb, when the headlights are off. But
> when you turn the headlights on, that path no longer leads to ground.
>
>
I'll give this test a shot later tonight and check.  I did not note any
dimming of the RF TS bulb, but I wasn't paying that close of attention to
it either.  I'll report if I find anything.


> What is left?  Presumably it is wiring, but what am I bypassing by
directly
> connecting +49 of the relay to terminal 30 of the fuse box?  Why can't
this
> be a permanent fix?

The + terminal normally gets power from the 4 way flasher switch,
> from different sources depending on that switch position. The allows
> that circuit to be off when the key is off, unless you pull out the 4
> way flasher switch. Bypassing this permanently could lead to a
> "surprise" at some future point when you're troubleshooting and not
> expecting that circuit to be hot. It could also lead to a dead
> battery if something when wrong with that circuit when the car was
> parked.
>
>
Your "surprise" point is well taken.  I was, in fact, surprised when I
connected +49 of the relay to terminal 30 on the fuse box.  When I
connected these, I heard the fuel pump relays click, which is not at all
what I was expecting and, from looking at the wiring diagram, I cannot see
why that happened.  Any ideas?

After I clean up the grounds, I'm starting to think I need to pull my
emergency switch and check all the connections.  I am fairly certain that
the PO installed a new wiring harness (unless VW used universal harnesses)
because my wiring harness contains wiring for an AT car, even though mine
is a MT.  I also vaguely recall hearing about an engine fire, which may
have necessitated a new harness.

I do not have the tool to pull the switches, is there a home-made solution
I can use to perform this task?
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