I've bought a PJ-3053 audio jack connector. I purchased it under the impression that it would have a microphone connection, but when I put in a TRRS jack, take a multimeter and measure connections, none of the pins gives a beep with the shield from the jack I plug in. It does have 6 pins, and comes with the following schematic: jack schematic.

Pin 7 is the ground it seems, pin 5 is left, 6 is right and the other 3 are unknown to me. I know there are jacks with detection in them, but for that just pin 2 and 3 would be enough, right?

  • \$\begingroup\$ some (most) microphones require power to be delivered through the jack before they can provide any output. \$\endgroup\$ Jan 23, 2020 at 18:44
  • \$\begingroup\$ Those six diagrams on the very bottom right on this picture gives you some sort of pinout. \$\endgroup\$
    – user103380
    Jan 23, 2020 at 18:44
  • \$\begingroup\$ @KingDuken Yes, but I have a hard time figuring out the actual functionalities of those pins. \$\endgroup\$
    – Arrrow
    Jan 23, 2020 at 18:47
  • \$\begingroup\$ @John I plugged in a TRRS jack male to male cable and used the multimeter from every ring to the pins on the connector \$\endgroup\$
    – Arrrow
    Jan 23, 2020 at 18:48
  • \$\begingroup\$ There is a Japanese website that I've used before that explains the pinout rather well. But you'll need to translate the page. \$\endgroup\$
    – user103380
    Jan 23, 2020 at 19:01

2 Answers 2


enter image description here

That appears to be a 3-pole jack with auxiliary switch.

Older stereo music systems typically used the jack socket switch contacts to switch on the internal speakers when the jack was removed. We can see this on contacts 5 and 2. The √ on 5 is the part that touches the inserted plug. When the plug is inserted the √ is pushed away from 2 so that the switch opens. It should be clear that the amplifier output would be connected to 5 and the speaker to 2. With the plug out the speakers will work. With the plug in the headphones will work but the speaker will be disconnected.

  • 7: Sleeve / GND.
  • 5: Tip.
  • 2: Tip pass through. Contact is closed when unplugged. Inserting the plug disconnects 5 from 2.
  • 6: Ring. My guess is that the black block is an insulated link which drives contact 4.
  • 4 & 3: These form an isolated switch that is closed when the plug is removed.

3 & 4 have no contact with the audio and so could, for example, be used to signal to a device that the headphones had been plugged in and the volume be adjusted accordingly.

It doesn't have a second ring connection for a microphone.

Continuity check confirmation:

  • No jack:
    • 5 & 2 are connected.
    • 3 & 4 are connected.
    • There are no other connections.
  • Jack inserted:
    • Sleeve to 7.
    • Ring to 6.
    • Tip to 5.
    • All other pins isolated.

This connector exists in several configurations (look at the diagrams on bottom right of the picture). If you don’t know the exact part number you figure out which one you have with a multimeter (like you did), but chances are that your version does only have two contacts...


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