How do you test a headlight switch for a 1989 200TQ Sedan?

[Kneale Brownson]

At 07:17 PM 5/7/2005 -0700, Dave Haupt wrote:
>My headlights just died one day, not so long ago. 


Your problem may not be with the switch itself, but rather with the wiring
harness connector to the switch.  I'll bet that if you examine it, you'll
see some or all of the plastic from the connector around the main
12-volts-in supply to the switch has melted from Audi arranging the power
to always go through the switch rather than through a relay triggered by
the switch.  The melted plastic means a poor connection to the switch.
You can try to clean that up, but I found that only helped temporarily.
The fix for me was to replace the connector with a short length of wire and
a "new" one inside a new plastic part.