S25+/U problematic 15v PD profile

[arianwen27]

This is going to be quite wordy, so bear with me.

The s25 plus and ultra support 2 charge modes. 10v 4.5a and 15v 3a. The s24 series only supported 10v.

Now, a usb cable is either normal or rated for 5a. To charge a phone at the full speed, you use a 5a cable, causing the phone to charge at 10v 4.5a 45w.

With the s25 series, you can use a normal non 5a cable, the phone will then swap to 15v 3a mode. Charging at 45w but with less amps. 

With that said, there is an issue with this system. For me personally, the 15v 3a mode never enables. I have to use a 5a rated cable to charge at 45w. This can be checked as 45w says super fast charging 2.0. Otherwise it says super fast charging (no 2.0). My charger isn't by samsung but it supports everything required for these things to work correctly.

Meaning if I don't have a large 5a cable, I cannot charge at 45w, a feature the s25 series should have.

You'd expect this to be a single device issue a shop can fix. Many other people have reported the exact same issue. Samsung italy officially said they knew there was an issue but the other way round. They found issues with devices using 5a cables and says not to use them till the issue is fixed.

To to sum things up. The s25 series can charge at 45w with a non 5a cable. But for me and many other people, this is not possible and a 5a cable is required.

An official charger shouldn't be required as this whole thing uses an open standard. But I'm not buying a second charger to test it.

Kinda curious how it works with others. Get your 45w charger, charge using a normal thin cable, than a 5a cable. Does the phone say super fast charging 2.0 both times and which charger are you using?

The cable that came with your phone is a non 5a cable

[johnz237]

For Superfast 2.0, you used to need a 45W, 5A cable; otherwise, it won't work, or at least it didn't in the past. I believe the S25U is more forgiving- as youve mentioned, IMO try with an offocial charger- as this could be the issue.. I believe you should still get 45W without it. Be sure to check charging speeds—it will say "X amount of time until charged,". Be mindful of not using an unofficial charger; such an expensive phone shouldn't risk using third-party chargers unless from companies such as Anker.

[arianwen27]

This is part of the issue. A 5A cable was required for the S24; Samsung added a system for 45W to work without a 5A cable on the S25. That system isn't working. There are people on YouTube showing that a 3A cable does support 2.0 charge speeds. The comments are 50/50 on whether it works for them.

And yes, I am not using an unknown charger; it's a 120W Anker charger I use with my laptop.

By S24 and S25, I mean Plus and Ultra, the ones that can do 45W.

[johnz237]

How bizarre. Do you have any other cables/plugs that support 45W? My charger works fine, unless this is a common issue—I haven't seen much on the forums.

[arianwen27]

Thats kinda my problem, I only own one 45w PPS plug so I don't have any others to test with. (The anker 120w one)

I had a look at the forums too, I don't expect many people to be looking for or caring exactly how their device is charging so I found nothing. There's news reports online talking about the feature and samsung youtubers talking about it as an upgrade over the s24.

The issue is mostly likely the phone not swapping to the extra voltage or not requesting it. It won't be a charger side issue.

Though without other plugs I can't test it myself

https://youtu.be/qTRY5LEX0eQ a video on it (this is part 2)

[arianwen27]

None of this is a problem anyone would notice. It's just an issue that exists that causes peak charge speeds to be lower than they should be. If you aren't looking for it or timing your phone charges, you wouldn't spot it

[Ziddy]

I can confirm, I have a Samsung 45w charger.

Plugged into it with old usb c cable.
Said superfast charging 2.0, full in 46 mins.

Plugged in using the cable that came with the charger, said superfast charging 2.0, full in 46 mins.

[arianwen27]

So we have you where it works, me where it doesn't. But you have an official charger... I have a feeling Samsung is doing something sneaky where it only works with their chargers. Though until we get someone with both a working and non-working charger, we won't know.

By working and non-working, I mean one shows 2.0, one shows no 2.0 when using a 3A cable.

[Ziddy]

I have no idea what A cable the other USB c cable is, there's nothing on it but it's an older cable

[arianwen27]

If it was an old cable, guesses are it's 3a. Unless it's for a laptop or something designed for high power, it'll be a 3a cable