^ nice schematic..... wat to use this for?

 

This circuit is for the benefit of those people (like me) who are unable to sleep nights because of being scared to death that their mini is going to spontaneously combust, burn down the garage and the house. as you can see in the diagram the only device's getting any power after the switch is thrown is the clock, the radio, (to retain memory) and the two flashing L.E.D.s (phony alarm) this has been working in my car for over 1 year, I also have the GIAC software upgrade without any detriment to its operation.

 

^^ aha, so this schematic disproves any need to be scared while
garaged inside the house? Isn't the combustion coming from a faulty
steering fan circuit or something? i forgot exactly wat was the
speculated circuit that contributed to spontaneous combustion...

 

This circuit completely Isolates the negative side of the battery from the chassis of the car, (with the exception of the clock, the radio,and the optional LED circuit.) So, to answer your question, there is NO power to the power steering fan circuit.

 

I'm glad I'm not the only one who doesn't want to become a NHTSA statistic.

 

A simple 'protection' circuit for those worried about their cars electrically self-immolating would be one of those gadgets used to prevent drive-aways/hotwiring using a switch and a fuse in the negative terminal circuit. These consist of a heavy switch in series with the negative battery terminal, with a small fuse inparallel with the switch. The idea of this circuit is one opens the switch when the car is not in use. The fuse now carries all the current in the negative battery terminal. The fuse, being only rated an amp or two is enough to maintain current flow for all the standby systems, alarm, etc. If someone were to try and start the car (or in the protection case, an electrical fault occurs) the fuse will open, cutting off all electrical power to the car. Closing the switch will restore proper operation of the battery, and in the case of an electrical fault, restoring the fuse first only to have it pop immediately will inform the owner that something needs further investigation.

 

Wouldn't this also prevent the electric radiator fan from running once the engine is shut off (ie: on hot days after a long run)? Might this lead to engine damage if the fan isn't allowed to run?

 

Yes, it will prevent the fan from running. You'd have to throw that switch when the car is cooled down.

 

very nice idea! the small fuse in parallel won't open
while the car is in operation because the larger wire with the switch
carries all the load.

 

Am I correct in assuming that in order to activate this setup, one would have to open the trunk raise the battery cover(cooper s) and throw a switch?

 

i believe so! no issue for weekend-only cars, but might be a little bit of
a hassle for daily driven cars... but you get the super piece of mind,
i suppose.