505 Central Locking system - Common Faults
PS (ps@mindfart.com)
Fri, 6 Mar 1998 11:27:05 -0500
The most common fault I know by far are the lock motors themselves. There
are at least two brands I am aware of; AOP & Kiekert. The AOP ones seem to
be crappy compared to the Kiekert ones. They will outright fail,
intermittently fail (wife lockout syndrome) or just make horrible screaming
noises to annoy you!
The second most common fault (especially with kids) is the "thermo-fuse"
located in the control box. This is a low-ohm resistor with a piece of
springy brass soldered to the top. When you "abuse" the locks, or a motor
is about to fail, this resistor will overheat causing the solder to melt,
which in turn will cause the brass spring to pop off, breaking the
connection, and finally disabling the locks! (Rube Goldberg lock protection
mechanism)
I purchased a self-resetting thermal circuit breaker rated at 10 amps and
installed this in place of the non-resetable "thermo-fuse" contrivance.
Never had any total failures since! I have only seen one instance of
corrosion causing failure, and that was in the fuse box! I bet if your
connector under the dash fails, you probably got it wet somehow.
-Phil Sadow