orange pulse no repsonse from controller

Hmm, well if it was charging when it got spilt on, then there's a very good chance that the battery (possibly the controller too) did get fried because water + active electric current = death for electronics. Since you did try to turn it on when it was most likely still wet it's probably dead. What I would do is still try to save it via rice, possibly even silica packets if you have them lying around. Do that for about 24 hours. Other than that you can void the controller warranty (if it still has one), and replace the battery.

Here's a guide for it: DualShock 4 Akku Austausch

Here's a battery: DualShock 4 (JDM-030 and Earlier) Controller Battery

If still no luck, see if Gamestop will take it. But from what I remember working at Gamestop, if it doesn't turn on, we don't want it.

My idea is that the controller is fully charged when you son dropped water on it and luckily suffered no damage try turn on the controller and rinse some of the charge then resync it to the PS4 hopefully it would work for you

Same thing has happened to mine.my 1year old pulled it off the charger and I found him with it in his mouth.the analogs and charge port had slobber all over.I ended up buying a new control cause I have no patience.lol but I haven't given up on the other control yet that's why I'm here to look for answers.lol

Sorry for writing 2 years after this thread was posted. I just had the same issue with my controller. It blinks orange once when the charger is inserted then goes off and nothing happens. I remember I left it fully charged, and it was just laying around for couple of days before I found out about this issue. Please if you found a solution let me know. I can afford a new battery but not a new controller :(