My 2016 Fiat 500X suddenly won't start after about 2 weeks since the last time it started. No lights, nothing. I thought it was a discharged battery, so I tried jump starting using a portable jump starter but still nothing happens.
I also tried with another battery charger + jump starter combo pack that I have but that did nothing either - wouldn't jump start nor does the battery seem to be charging.
(And yes I did ensure those packs are charged and working.)

Could I be connecting it wrongly on the battery terminals?

I have attached a picture here showing where I connected the positive and negative clamps.
I connected the positive (red) end to the position marked in a RED circle in the picture - you will see two RED circles in the picture because I tried these two positions (separately).
I connected the negative (black) end to a nut marked in a BLUE circle on the picture. I couldn't find anywhere else suitable to connect to as a "ground".

Finally, a note:
Sometimes, after connecting and turning on either of the two jump starter / battery charger packs that I have, the car would make a loud warning alarm kind of sound at about 1-second intervals or so. I would have to turn off the packs and reposition the positive and negative clamps and then it would not sound the alarm when turning on the packs again. I don't know if this information helps figure out the problem, but just thought of adding it here.

Either of the two terminals you have ring in the picture are OK. The are in fact one and the same. The battery main terminal is connected directly to that upper plate with the tab and extra bolted terminals.

I think you need to get the battery out and replaced with another known good one. I think the current battery is totally dead or requires an "out of car" charge/reconditioning.

I'd second taking the battery out and charging it on the bench.

If you have a voltmeter, measure the voltage. It should be 12.3V or very close to that. Anything less than 12V (e.g. 11.5V) is unlikely to start the car.

If you bench charge it, stick the charger onto the respective +/- poles of the battery. It'll take a good 8 or 9 hours to charge a large battery (if your charger has a manually adjustable charging rate, set it around 1.5A/h). Leave it charging all day or overnight.

When it's done, remove the charger and give the battery some time to rest (measuring it immediately gives you a false high reading). Half an hour ought to do it (so go have breakfast while it's resting).

The voltage should be 12.3V. If it's less, the battery is likely terminally knackered, so replace it. If it keeps its charge it can go into the car.. but if the voltage drops again overnight after you've been using it, then the battery could still be terminally knackered … just not as much as if it doesn't hold charge at all... or the car may be not charging it enough (less likely but a possible one) in which case a new battery would also go flat after a few uses.

But most likely candidate is the battery is in poor shape and may or may not recover after some charging.


Ralf S.

How old is the battery? Does not look like the factory one? As Ralf says - have you put a Voltmeter on it?

Does it turn over or just nothing?

If the latter I would check the wires from the battery to the starter and to the car body and engine. They can rot through/corrode which stops the car from running/starting