I have a weird electrical power supply problem. I was hoping maybe someone else had something similar and some ideas into what is going on.

The first symptoms were sporadic power to my radio head unit. It would randomly power cycle off and on.

This morning on the way to work I noticed that if I tapped the brakes all the power to the engine would cease for half a second or so. The tach would turn off as well as the voltmeter. I played around with it my whole commute this morning. Turning the headlights on would also cause a loss of power to the tach and the voltmeter but it didn't seem to be affecting the engine. The overhead lights, electric windows, and the sunroof had no noticeable affect. Any ideas what could be going on?

 

Also, as soon as I turned the car off all electrical went dead and the car cannot be jumpstarted

 

Check your engine fusebox and battery connections/cables.

 

Do what the old man said and check the battery as well. At idle the car uses the battery for power, the alternator doesn't put out much juice when it's spinning slow.

Have you had problems starting it, does it crank slow?