Hi everyone.

So I've been working on this 99 S80 and just finished a oil trap pcv box and alternator replacement. Finally got it all back together and drove great all night last night. I took it to a drive-through car wash last night and let it sit outside overnight and when I went to start it today there was no power to anything other than the door locks make a sound when you open the doors, but not every time, and the glovebox light and light under my dash that shines on my feet and pedals. No ignition or accessory power, no dome lights, factory car remote won't lock or unlock the doors. Nothing. When it turn the key there is no power or no electrical noises like clicks or chimes. There isn't even the glow coming from the ignition keyhole green right. Nothing. I'm curious as to why my remote doesn't even work. I sure hope this isn't my computer.

I even purchased a new battery today thinking this was the problem as the battery I put back into it died and froze too many times. Even the new 1000 CA battery didn't fix the issue.

I'm not sure if washing it has anything to do with what's going on. But it was just a thought as some older cars don't like to go through drive-through car washes and work well the next day.

Does anyone know what would cause this issue? ECU?

Thanks in advance for any help

 

No-power-to-anything is the symptom? That is not caused by the ECU.

 

There is only power to the following electronics

- hazards switch/button

- door locks (makes the usual buzzing noise when you open the doors BUT the power locks buttons don't work and neither does the remote locks

- the lights underneath the glove box that shines on the passenger's feet and also on the driver's side where the pedals are.

That's it. It's not a battery issue (purchased a new battery yesterday), or any connection issues to the battery, and the fact that the factory remote that was working right up till yesterday morning is no longer working or communicating with the computer, as well as having absolutely no power or signs of life on the headlights, dash, stereo, or any gauges makes me think my issue has something to do with the central computer.

 

First, there is no "central computer". There is a computer for the engine, transmission, HVAC, air bag, etc. You have symptoms of an electrical failure.

I doubt that the car wash had anything to do with it. Start by checking the fuses in the underhood panel. It sounds to me like one of the large capacity fuses is blown.

 

I'd start at everything I touched when I was replacing the alternator.