Z3 Roadster (E36/7) electrical problems

hi everybody
problem with my z3, details are that it is turning on abs warning light, which will then go out on restart, also when i flick headlights to dim and back the radio goes off !!
also when hit the brake the headlights flicker and the new trick is that the key when turned does not work,no power,but turn it on and off and it will work.
car did leak this summer and was lot of water behind passanger seat,so wondering has something got wet ??
mechanical problems i can handle,electrical problems i have no idea !!!!
thanks in advance
Leo

start [no pun] at the battery and check ALL connections

That is certainly a strange group of symptoms, however I keyed on one issue: the brakes cause the headlights to dim. That sounds like a bad ground somewhere that is causing a high-resistance circuit that works OK until a lot of current goes through it. Since there are so many other issues, I would inspect the battery connections and grounds.

Another source of strange electrical problems is the wire harness at the trunk hinge. You could look there.

The water in the passenger compartment could be to blame since the battery wire goes through there. It is also usual to set the ABS-fault light when that happens. However, I'm thinking you have water in the trunk, around the battery.

It appears you have a lot of troubleshooting to do. Good luck.

Some links regarding the trunk wiring. It does not necessarily have to be as bad as the linked photos show. There is also a TSB link that BMW put out regarding a repair kit. You might have to inspect the wiring very carefully to find a broken wire within the bundle.

http://forums.bimmerforums.com/forum...04&postcount=6