OK, so this one is a little odd...

I loaded up my car with my gear to build my sub enclosure, hopped in the car, put the key in, turned it to run, and BAM! completely dead.

I check the battery and main fuse. OK. 12.8v, fuse is carrying power. I have power at the underhood fuse panel and jumper point. Its symptoms are of a disconnected battery.

Any ideas??

 

Ground strap in the engine bay on the passenger side, I've had two corrode on me.

Also I've had the connectors to the battery terminals be at fault but that usually reads low 12s for the voltage when it's the culprit. Next I'd check the ground for the ECU fuses, drivers side, front side of strut tower near where the ECU and wire loom guide connect to the engine mount.

Then check the + terminal next to the airbox, make sure that bolt is tight, if it's come loose at all then the fuses won't get enough power.

Then check the power steering fuse, it's shared with the starter, so over draw on that will prevent a start, and then if that's not it also check your PS fluid levels.

How is the sub powered? Is your ECU retaining any memories? (low power trickling through vs no power trickling through)

(I did this many times with my 05 in the dead of winter this year so I feel for ya)

 

Got it, it was the main relay.

Damn cars...

 

I'm having the same issue. Can you tell me where the main relay is and the ground strap?

Thanks!

 

Main relay is in the under hood fuse box. It is the relay furthest to the front of the car. Just swap it with the AC relay behind it and see if you get power.

Check to see if you are getting power to the fuse box at the lug on the rear of the box, if its dead, check the main fuse next to the battery. Also check for continuity across the pyrotechnic battery disconnect.