jdalma2

The car sat for a week while I was out of town for work. Came home yesterday and found the S8 completely dead, no power at all. None of the lights came on and absolutely nothing happened when I turned the key. I figured I left a light on somewhere and it drained the battery throughout the week. Couldn't find any switches left on, so I decided to throw the battery on a trickle charger. Turns out the batter was already pretty much fully charged and I don't have a dead battery issue. Is there a main fuse between the battery and the rest of the car? I'm at a little bit of a loss right now. Any thoughts?

Jeff

Oxnardo Ring

So, interior lights don't come up when you open the door and the dash doesn't light up when you turn key part way? Just trying to get a handle on whether the car's completely dead electrically? Clicker doesn''t lock and unlock doors? Just trying to get a handle on how dead, dead is... since I've not seen this one before.

jdalma2

Yes, the car is completely dead. No interior lights, no remote unlock, no lights on dash (mileage, clock, etc.), and absolutely nothing when I turn key.

Oxnardo Ring

OK< sorry. Not to be dense, but that's a new one. The good news is that it shouldn't be hard to track down if you are certain the battery is good... just for grins have you "Jumped" it with an additional battery via cables to the battery in the trunk? Still no lights?

If that's the case, and both battery post leads are in good shape with no corrosion, then I'd next check to see if +12V is getting beyond that funky interconnect-junction beneath the passenger (US models) footwell. All the power distribution runs up the right side of the car.... are you getting power to the front of the vehicle via that main feed and interconnect?

jdalma2

I just grabbed a multimeter from the auto store, so I'll dig into the passenger footwell and take a look.

Oxnardo Ring

And, just to clarify, the interconnect is beneath the car-- you can see it where the "monster battery cable" from the back emerges with a junction block to feed the electical system and another large wire over to the starter. It's not far from the right, front wheel well cover in an indent in the frame.

But a good place to check to see if you have power up front is on the fuse block behind the kick panel on the passenger's side. Most of the fuses are in there so you can see where any of the "live" circuits are actually live.

jdalma2

Crisis averted. Tested the voltage up front. Turns out I was only getting 2.78 volts up front. Retested the battery and it turns out the battery is shot and only had 4.1 volts (or so). I'll admit I do feel like a moron for not figuring it was a bad battery sooner. Thanks for the help anyways! I did figure out why my rear heated seats weren't working though so thats a bonus.