If the battery cutoff switch were fitted correctly it would prevent the
handbrake or anything else from discharging the battery, it isn't clear from
your post whether it did or not. The handbrake switch is connected to the
green circuit, which of course should be isolated when the ignition is off,
assuming the wiring hasn't been tampered with. If there were a stray 12v
source connected to the green then dropping the handbrake and hence opening
its switch would make almost no difference to any drain as there is a very
low impedance path to ground through components on the white like the
ignition and fuel pump which can be 'seen' through the green circuit fuse.
So the implication is, that if dropping the handbrake really did make a
difference and wasn't just coincidental with some other change, that the
stray voltage is on the green/orange. With the handbrake pulled up this
would indeed leak through to the fuel pump and ignition. With it down it
would just be connected to the brake imbalance switch which should be open
anyway (and if it weren't the other side being connected to the green would
negate the dropping of the handbrake), and the handbrake warning lamp. This
latter is also connected to ground, but will offer a much higher resistance
path than the fuel pump and ignition and hence any battery drain will be
much less. And with the handbrake down you may well see it glowing
slightly. For this to be the cause of your drain there has to be a 12v
source connected to the green/orange somewhere, like from a brown or a
purple (remove the purple fuse to tell which) and so is either a damaged
loom or bad wiring modification.
In any event you should be able to detect a drain while parked by connecting
an analogue voltmeter on its 12v scale in place of the battery ground strap.
If you see 12v registered you have a drain. If you only see a few volts
registered this is the normal reverse leakage of the alternator diodes which
is in the order of micro-amps and can be ignored. The first step in
locating the source of a drain is always to remove the alternator plug and
see what happens to the voltmeter reading, then the purple fuse, the hazard
flasher in-line fuse, then browns from ignition switch, main lighting
switch, starter relay, ignition relay, and finally the solenoid.
PaulH.
----- Original Message -----
From: <Aeseeyou@aol.com>
To: <mgs@autox.team.net>
Sent: Saturday, July 31, 2004 4:44 AM
Subject: Short in the Hand brake, long in the misery!
> I have probably written to the list before about the TBS or Tired Battery
> Syndrome I've been suffering from lately. It has really perplexed and
puzzled me.
> Until yesterday, when I think (or Hope) that I've finally found the source
of
> my problem. Yesterday for the first time in a long time for some reason I
> didn't set the hand brake when I parked the car. And lo and behold,..today
when I
> went to start the car it really started up like it had a fresh battery or
a
> full charge....
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