Tripped the alarm now havoc

[Ross]

This isn't the E34s listed above it's a '99 528i (E39).
I bought this a week ago and it has mostly been sitting but always started right up.
This morning I tripped the alarm somehow, I didn't know it was even set.
When I then tried to start it made popping noises from one of the speakers a nd no crank. Later nothing, with a jump when the key is turned it clicks very loudly under the hood about twice per second. All the lights that would be on during starting also flicker with the same cadence.
There is definately a draw when everything is off, a good spark from the cables when connecting.
Any ideas what I did? I suspect it's alarm related but know zip about E39s.
I'm really hoping some computer just wants to be reset.

[shogun]

Read the owners manual. As far as I remember from the E34 and E32 there is info about that in the manual. Disconnecting the battery for 15 minutes etc pp.

[Ross]

Nothing in the manual other than how to work the remote. The battery is now disconnected and on a charger. All fingers and toes crossed here.

[Ross]

UPDATE
After disconnecting and recharging battery all was fine.Was being the important word in that sentence.
This morning it's dead again with odd sounds coming from the speaker in the right front door when a starting attempt is made.
I'm thinking perhaps a relay has fused itself.
I have no service info on this car, can someone point me to a good online reference until I can get a Bentley for this?

[Ferret]

Put a current meter in series with the battery and start pullin them there fuses till you find which one causes the current to stop flowing.

Do NOT switch on the ignition while you've got a current meter in the circuit - you'll blow its fuse.

[gmannino]

I agree with the above comment, fixes draining batteries everytime. A test light would work also(only test lights with incandescent light bulb.)