My phone has stopped working with Android Auto a couple of months ago. After pulling the head unit and replacing the USB lead and updating head unit firmware without success my attention has turned to the phone. My wife's phone still works on Android Auto
Memory is hazy, but within a couple of weeks, I'd:
1 Cleaned the fluff out of the phones USB port.
2 Broke a 10,000mA power bank (can see something got hot inside).
3 Android Auto stopped working after flashing up an over current warning whilst my phone was connected.
The phone still charges through the head unit and other devices, you'd think the head unit would flash up another warning unless the fault was related to date transfer or high speed charging.
Does anyone know how to test the port? I could sacrifice a USB lead and grab the multimeter, but what values should I expect...phone off? What's the max current draw and I suspect different resistance on the data pins will tell the phone how much current it can pull. It could be something like a dead short that's telling it to fast charge so I'm a bit hesitant to plug into anything except a dumb charger.
(Connected it to the wife's new car head unit the other day and noticed it it started and stopped charging a few times... Hopefully didn't damage the radio!)
You can get usb c current/voltage monitors pretty cheap on eBay or Amazon. Maybe try one of them for the first step?
1 Cleaned the fluff out of the phones USB port.
... with? Have you used something sharp / metal like a paperclip and shagged all the connectors?
Plugging it into something else is the obvious answer, don't you have a computer in the house? And try a different cable, USB is a finicky car-crash of technologies and compatibilities. If it charges then I'm unsure what a multimeter is going to tell you.
Thanks IA.
Cougar, yep the old paperclip as I was on holiday with minimal stuff 🙂
The point is I don't want to plug it into anything like a laptop incase it damages the port.
A multimeter will tell me lots of stuff such as resistance between the pins, current draw for different resistors across the pins (as I think that's how the phone knows whether to draw 500ma from a tiny power bank or 3 amps from a high speed charger.
I'll order a current monitor as suggested but I bet there is a techy site somewhere with details of the expected values for the pins...I just haven't found it yet!
If it's genuinely shagged then you don't need to know specific resistance values - just look for low numbers between any of the pins to GND.
The most basic chargers just let the data pins float.
This is the best way to test it - don't forget to flip the cable over and test the other side.
Wow, didn't realise how many pins were hiding in there compared to legacy USB...24!
I imagine many are not used for the phone but I can see 16 in two different USB cables, some are probably unconnected. I've found a tester for £19 which includes some croc clips for messing about, also a new port for the phone is £15 but in my experience the phone is never great after open heart surgery and would probably ruin the screen taking it apart...
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All I will add is Android Auto and respective car hardware and phone can be a nightmare.
I've had cables stop synching all of sudden. Android auto itself stop working completely. Weird drop outs occasionally.
My advice get an absolute premium cable you know to carry synch and power consistently.
For what it's worth.
I do not think it's as simple as you think it is. It's not like a light bulb, USB is a client/sever protocol, your multimeter is neither of those things.
You can get specific in-line USB-C testers but even if you discover yes, it's broken, then what?
For the price of tools and parts (and the risk of buggering it up even further), you could just take it to one of those dodgy High Street "we fix fonez!" places. Assuming, of course, that a warranty repair isn't an option.
Yes, as cougar says there’s negotiation before current delivery with usb-c PD. Which includes selecting voltage which can be 5,9,15 or 20v (at a variety of amperages). Add in 12v for some android stuff too…
Thanks, yes going with the usb tester as if it shows the phone trying to pull 3 amps through an unsuitable charger that confirms there is a fault somewhere.
I've changed all the leads and used an OE lead on the Android auto unit, works every time with my wife's phone, never works with mine!
The only painful bit is I'd rather upgrade the head unit than blow £300 odd on a new phone 🙂
If it otherwise works, you could get something cheaper and dedicate that just to Android Auto duties?
My previous phone really struggled, but my current phone is a Nokia which cost £200 two years ago and it works just fine.
Interesting idea Cougar, got my old phone lying around and it could double as a basic tracker if I hid it out of sight behind some dashboard trim, I think I can add sim cards to my mobile/broadband account...
Or you could tether it to a Wireless Hotspot on your main handset if you didn't want to pay for a second SIM.
I mean... it can't hurt to _try_ at least, right?
You say you replaced the USB lead, are you sure it is compatible with the phone? USB-C has so many possible uses and cables are not all the same. The wrong cable can result in reduced data speeds or function, and a wrong cable that hasn't been manufactured to the full spec and is missing some of the protection can damage the device.
Yeh I've tried original leads, work fine with wife's phone and now my old cracked one is plugged in and working... It's definitely this phone.
It's a Google Pixel 3a and strangely, Google's own phones tend to have problems with Android Auto, it's not been able to read out messages, put speaker phone through to the radio or do any speech recognition for over a year...so using my old Samsung phone is actually offering full functionality compared to just maps and music on the Pixel.
