OK. Car acts like dead battery. No lights, clock, radio,start. Just dead. Opened hood alarm went off. Dome light on, clock on, car started. Drove 60 miles stop twice car acted normal. This morning car started and immediately died, no dome light, clock nothing. Wondering if Camry has a main relay, I.E. battery relay or such. All help is appreciated. Thanks

 

No power until the hood was opened and alarm want off? Is this a factory installed alarm or user installed?

Power distribution depends on the circuit.

Some circuits receive power via fuses direct from the battery. Others need a relay to be powered.

The hazards lights and dome are powered direct from battery.

Have you check the battery cables? Typically if no power the issue is the battery cables or battery. Perhaps opening the hood and alarm resulted in a poor electrical circuit now making contact.