Retropie in my Mazda-- Low voltage problem

Maskedsquirrels

@lostless - thanks I might go this route

@steptoe - thank you for all the links, I like the double power supply that may just work.

Bluescreen

Pi3b+ need 5,1 volts. standart usb charger only have 5 volts.
i have with 5 volts the same problem. 5.1 volt 2 amps works

grant2258

i got a 2.4 amp charger for the car from b&m that should be enough to run the pi with a decent usb cable the cheap ones loose too much current

lostless

@grant2258 Also shorter the cable better. I can run a pi3 off a external USB battery, but using a short 6 in cable, otherwise i get the dreaded low voltage warning.

grant2258

well longer cables should be fine that why some are cheaper than others.

lostless

@grant2258 wire has resistance. the longer the cable, the greater the voltage drop. for charging a battery, not a big deal, but for a pi that requires the full 5V, it can cause issues. the official pi power supply cables are at least twice as thick than what i usually see in a standard charging usb cable.

grant2258

exactly anything 1m and below should be fine if its using the right awg wire the budget ones are far too thin. https://www.engineeringtoolbox.com/wire-gauges-d_419.html

Daistaar

I recommend you get a Power adapter capable of outputting 5V at 3 amps. It's had my Pi running without power issues, although i should mention that I've got nothing plugged into the USB ports (...on the Raspberry Pi) that would draw additional power. I'll post the items I used if we're allowed. If linking is frowned upon, I'll delete them or a Mod can remove them. Note that I AM using the USB ports on the 3-socket car adapter to power other devices. I'm charging my cheap-o Shanwan PS3 Dualshock 3 Controllers through the socket with the 5V, 1amp ports but nothing goes in the Pi USB ports. It should also be noted that I had this setup with a NESPi+ case before switching and kept getting the low power icon. It still worked but the icon drove me crazy. Case swap made that go away and it didn't matter since the Pi is hidden under the passenger front seat.

Smarza case (Great Airflow and stays below 43 degrees in the car)
Choetech Car adapter (it says the USB-C port outputs 5V at 3amps)
3-Socket 12V Splitter To connect peripherals and add kill switch to Pi.
Generic HDMI Splitter Because 2 headrests...
3-input HDMI Switcher (replacing as I now realize I'll need a remote for when it's tucked away)

I'll include images of the madness I've made and hopefully it's not too far off from your Mazda setup.

Daistaar

Here is the 3 Socket adapter with Power running through the ChoeTech adapter.

Car Charger to supply enough power to Pi without bolt issues

Running to Pi 3B+ with a generic braided USB-C to MicroUSB cable

HDMI out from Pi to an HDMI Switcher (additionally a Firestick is there but removed to minimize confusion)

HDMI Switcher to HDMI Splitter...

And Lastly.... HDMI Splitter to Car Headrests (Sending them back as they aren't comfortable; Awesome monitors, lousy headrests)

Daistaar

Look Ma... No Lightning Bolt!