After fixing my coolant problem the other night, I drove my 85 Westy to a
jazz band rehearsal.  When I got to the rehearsal site, I noticed I had no
brake lights.  Came home very carefully afterwards and proceeded to analyze
the situation.  Here is what I have discovered along with some questions for
the whizzes on the list:

-- When I remove the left rear tail light assembly, unplug the cables, and
put a voltmeter across the brakelight wire (black/red), I notice it reads
battery voltage without the brake pedal being depressed.  (The PO had put a
splice in the wire which I disconnected, so there was no load from the right
light on the circuit.)

-- When I reconnect the load, the voltage drops to around 2 volts -- not
enough to light the bulbs.  With the tail lights connected, but hanging by
the cable, the brake lights work properly.  When I re-install the tail light
assembly, the lights stop working.

My first hypothesis was that I have a bad brake light switch that offers a
high resistance path when open.  With no load, there would be no current,
hence no voltage drop across the switch, and I would read 12 volts.

It's not that simple, however...

According to my Haynes manual, the output of the brake light switch connects
to a point on the voltage regulator (C1 in the Haynes book).   C1 is in turn
jumpered to a point labeled E16, which is not identified in the manual.

It seems to me that this connection to the regulator could be the source of
the 12 volt reading on the tail light switch, but I don't have enough
information to confirm this.

So,  my questions are:

1.  Why is this brake light circuit routed through the voltage regulator?

2.  Can anyone tell me what/where Haynes point E16 is???

Thanks in advance for your help out there in Vanagon Land!

Dave in KC
85 Westy (with no brake lights, but a working cooling system)
http://members.fortunecity.com/davebaker1