[Device Repair] R7027:
In the service manual for Galaxy S7 (SM-G930F), step number four in the flow chart for troubleshooting power-on issue is to check the voltage level of a "signal".

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I had a very hard time locating this. I didn't understand what it means to check for voltage of something by its signal name, and it's location was not described in the service manual (not that I could see in my four chapter excerpt of the complete manual). Then I learned that this signal name needs to be translated into a test point (TP) ID on the board. This is unlikely to be referenced in a service manual. So unless you have circuit diagrams for the phone, you will have a very hard time knowing what signal name translates to what test point on the board.

In my search for a test point for this signal, I have found where it's located on the Galaxy S2 (GT-I9100).

This is where it's at on Galaxy S2:

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I think I have located a test point for it on the Galaxy S7 Edge (SM-G935F) and the Galaxy S7 (SM-G930F) as well, but I'm not sure if I have the right idea on how to probe it.

This is where it's at on Galaxy S7:

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This is where it's at on Galaxy S7 Edge:

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Can someone confirm please? Is TP7002 the test point for AP_PS_HOLD on Galaxy S7? As you can see, on the Galaxy S2, the test point looks like a proper test point, in the form of a copper contact pad. But on Galaxy S7 and Galaxy S7 Edge, it looks like it's protected by a layer of paint/coat, if it is a test point at all. So I'm thinking about scratching or scraping that layer off so I can get down to the copper. Is that the right idea here? I have never seen a test point looking like this, and I know what a test point usually looks like. @Renate I would appreciate advice on this.

I could not find a good picture of the Galaxy S7 Edge board. And I only assume that TP7002 serves the same purpose on the regular Galaxy S7. I don't know this for a fact. I don't know most of these things for a fact. Also, if it says to "check the signal", does it mean to use an oscilloscope? If it needs to be a steady 1.8 V, can I not check it with a multimeter? I don't need to see what the signal looks like?

My source for Galaxy S2 test point:

Samsung S2 (GT-I9100) Fehlersuche mit Servicemanual (Werkstatt Samsung)

Hallo, ich versuche eine Galaxy S2 Hauptplatine nach der Fehlersuch-Anleitung im Servicemanual zu reparieren. Ich scheitere aber schon bei diesem Test: Check the U501 output signal (AP_PS_HOLD(TP) >2.8V) (TP) ist wohl ein Testpunkt? Ist aber nirgends zu finden. Wo kann ich dieses Signal sonst...

www.android-hilfe.de

My source for Galaxy S7 Edge test point:

Samsung S7 SM-G935F, AP_PS_HOLD - GSM-Forum

Hello. I have a Samsung S7 which cannot start. accordingly to the repair guides I should check R7027 and AP_PS_HOLD. R7027 voltage is high when start

forum.gsmhosting.com

Image source for Galaxy S2:

Samsung Galaxy S 2 (International) Review - The Best, Redefined

www.anandtech.com

Image source for Galaxy S7:

Own work.

Diagrams with annotations:

Own work based on service manuals.