I have a Volvo S90 2018 It was in the garage for more than 45-days. Did not start - Tried a Jumper Start - nothing happened.
It does NOT show any light. It seems that the battery is dead. But I cannot open the Trunk where de battery is.
How can I open the back trunk? Could some one help me? Truly Ademir Soares

 

You found the jump start port under the hood - apply 12v to that and that will charge the battery and/or provide enough power to unlatch the trunk lid -

If your "jump start" connections did not allow that - your cables or connections were bad or only capable of providing a minimum amount of current. You may have to keep things connected (or connect a proper battery charger) for 1/2 hour or so to get enough current in the battery to be able to open the trunk

If the battery sat dead for a period of time - the battery is probably permanently damaged.

 

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