My S40 2008 didn't start this morning. When I turn the ignition key all power went off in the car. There was a ticking noise under the passenger side glove box (inside the fuse box). I waited a little bit and the display came back. I turned the key to position 2 and the power went away again. Removed the key and waited a minute or 2. Put the key again, all seems Ok, turn key in position 2 and lost the power again. Any clue of what is going on?

Thanks for the help

 

Sounds like a bad battery (or bad battery cable connection). When you turn the key to START you are commanding full cranking amperage and everything shuts off as the battery voltage goes well below the required 12-14 volts.

Easy check is with a digital multimeter set to DC volts. It should be about 12.5 volts. Or try jump starting the car with another. These are cheap and easy tests to see if it's something simple or more complicated.

 

You are right.When I tested the battery first I had 12.5 volts. But as soon as I try to start the car, the voltage dropped to 8 volts. The voltage climbed slowly to 12.5 volts again. I will change the battery tomorrow.

Thank you