One of the front USB ports in our new 2023 does not work for CarPlay or charging
12-10-23, 11:51 AM
#1
6th Gear
Thread Starter
Help? Strange - both front USBs power in and out
Have a 2023…just today, both of my front USBs, power on for 10-12 seconds, power off 1-2 seconds, and back on in this same cycle….what in the heck is going on?
…had a small USB light and my iPhone cord plugged into my phone…both power off and on in that interval. I unplugged both, plugged just one in…still the same.
…fuse failing? Where/what number is the fuse for it? What else could it be?
11000 miles…bought it new…very very odd.
…had a small USB light and my iPhone cord plugged into my phone…both power off and on in that interval. I unplugged both, plugged just one in…still the same.
…fuse failing? Where/what number is the fuse for it? What else could it be?
11000 miles…bought it new…very very odd.
Popular Reply
02-18-24, 11:36 AM
New member. Bought mine yesterday. Saw this thread and tried my front ports with my iPhone 15 Pro Max. Sure enough, the top one doesn't reliably work. 10/23 date of manufacture.
Now for the fun part...I'm a USB engineer, and not to dox myself too much, but I helped write the specification and have supported this interface professionally since inception. It's kinda like my baby. Anyway, as a good (?) USB engineer I of course had some old interface analysis hardware laying around at home so I hooked it up and took a peek at what's happening.
TLDR: this looks like a power problem exacerbated by the inclusion of Type-C on the new iPhones.
In the olden days, USB Type-A connectors (these are the ones in the GX) were expected to always supply 5V (+/- .25V) @ 500mA (minimum). As time went on the spec was changed to permit up to 5.5V volts which provided a little bit of headroom for very long cables (the longer the cable, the greater the voltage drop from end-to-end). The GX is using the old standard and provides ~5V all the time. It also has very long cables. You can see where this is going...
With the introduction of Type-C, the same connector can provide a huge array of different voltage and current profiles, but in order to do so safely it has to "negotiate" with the attached device.In most cases, this requires a special chip that helps both end of the link arrive at the highest common profile and THEN the power is turned on. Makes sense if you think about it...a laptop and a cell phone have very different powering requirements so the resulting negotiation would also be very different. Don't feed 20V to a device that can only handle 5V!
Now that we have the power part understood, there is a bit of an added wrinkle in play here: CarPlay. In the USB world there are Hosts and Devices. The Host is the one running the show and the Device pretty much just does what it's told. In this relationship the HOST is also the one supplying the power. CarPlay turns this around a bit in that your phone is the Host, it runs the show, but obviously we also want to charge our phone from the car so the power profile is reversed. The phone is still the boss, but it is getting power from the car rather than the other way around. This also takes some negotiation which is handled by the CarPlay protocol in that when the phone is first plugged in, it's a Device initially, it then tells the Host (the GX) "Hey, I want to be the boss now, but you keep providing the power" so the two do what's called a role-swap. Both sides are now happy. GX driving power to the phone, phone driving data (CarPlay) to the GX.
Sorry, I know this is long, but the problem is that the GX power delivery to the top socket is marginal for the Type-C enabled iPhones. The iPhone gets plugged in and the USB voltage "droops" below the minimum permitted which causes the GX to sense this, turn it off, and then back on again. I see it on my analyzer. This in turn causes the phone to restart both Type-C and CarPlay negotiation and the cycle may/may-not repeat. I do not see this getting fixed by Lexus as the cable length and power delivery can't be (practically) changed. Apple may be able to provide an update that reduces the inrush current to the Type-C controller, which would help prevent the voltage droop, but I wouldn't hold my breath as they are operating within today's specification. A "new" GX USB insert may temporarily fix the problem, but it will reappear as the connectors age.
Suggested solutions:
- Only use the bottom socket. Duh.
- Use wireless CarPlay with a 3rd party adapter. I'm betting the top socket works fine in this case because no Type-C negotiation is required and the in-rush current is probably more tightly regulated. This is likely what I will do as the charging current provided by the GX is woefully small for today's phones anyway. No sense in owning a phone that can charge at 20+ watts and then plugging it into a socket that can only supply 2.5 watts (5V @ 500mA).
- Try different cables. The shorter the better. This is unlikely to be a permanent solution.
If the engineers at Lexus/Toyota are reading this: You should have cranked your VBUS capacitance on both ports in ~2014. The spec says "minimum 120uF for Hosts", but the spec also says your topology shouldn't permit in-rush current induced droop of < 4.75V at the connector. If you can't make the latter work, you needed to increase the former.
Now for the fun part...I'm a USB engineer, and not to dox myself too much, but I helped write the specification and have supported this interface professionally since inception. It's kinda like my baby. Anyway, as a good (?) USB engineer I of course had some old interface analysis hardware laying around at home so I hooked it up and took a peek at what's happening.
TLDR: this looks like a power problem exacerbated by the inclusion of Type-C on the new iPhones.
In the olden days, USB Type-A connectors (these are the ones in the GX) were expected to always supply 5V (+/- .25V) @ 500mA (minimum). As time went on the spec was changed to permit up to 5.5V volts which provided a little bit of headroom for very long cables (the longer the cable, the greater the voltage drop from end-to-end). The GX is using the old standard and provides ~5V all the time. It also has very long cables. You can see where this is going...
With the introduction of Type-C, the same connector can provide a huge array of different voltage and current profiles, but in order to do so safely it has to "negotiate" with the attached device.In most cases, this requires a special chip that helps both end of the link arrive at the highest common profile and THEN the power is turned on. Makes sense if you think about it...a laptop and a cell phone have very different powering requirements so the resulting negotiation would also be very different. Don't feed 20V to a device that can only handle 5V!
Now that we have the power part understood, there is a bit of an added wrinkle in play here: CarPlay. In the USB world there are Hosts and Devices. The Host is the one running the show and the Device pretty much just does what it's told. In this relationship the HOST is also the one supplying the power. CarPlay turns this around a bit in that your phone is the Host, it runs the show, but obviously we also want to charge our phone from the car so the power profile is reversed. The phone is still the boss, but it is getting power from the car rather than the other way around. This also takes some negotiation which is handled by the CarPlay protocol in that when the phone is first plugged in, it's a Device initially, it then tells the Host (the GX) "Hey, I want to be the boss now, but you keep providing the power" so the two do what's called a role-swap. Both sides are now happy. GX driving power to the phone, phone driving data (CarPlay) to the GX.
Sorry, I know this is long, but the problem is that the GX power delivery to the top socket is marginal for the Type-C enabled iPhones. The iPhone gets plugged in and the USB voltage "droops" below the minimum permitted which causes the GX to sense this, turn it off, and then back on again. I see it on my analyzer. This in turn causes the phone to restart both Type-C and CarPlay negotiation and the cycle may/may-not repeat. I do not see this getting fixed by Lexus as the cable length and power delivery can't be (practically) changed. Apple may be able to provide an update that reduces the inrush current to the Type-C controller, which would help prevent the voltage droop, but I wouldn't hold my breath as they are operating within today's specification. A "new" GX USB insert may temporarily fix the problem, but it will reappear as the connectors age.
Suggested solutions:
- Only use the bottom socket. Duh.
- Use wireless CarPlay with a 3rd party adapter. I'm betting the top socket works fine in this case because no Type-C negotiation is required and the in-rush current is probably more tightly regulated. This is likely what I will do as the charging current provided by the GX is woefully small for today's phones anyway. No sense in owning a phone that can charge at 20+ watts and then plugging it into a socket that can only supply 2.5 watts (5V @ 500mA).
- Try different cables. The shorter the better. This is unlikely to be a permanent solution.
If the engineers at Lexus/Toyota are reading this: You should have cranked your VBUS capacitance on both ports in ~2014. The spec says "minimum 120uF for Hosts", but the spec also says your topology shouldn't permit in-rush current induced droop of < 4.75V at the connector. If you can't make the latter work, you needed to increase the former.
12-12-23, 06:47 AM
#2
any debris in the connectors? potentially a short. the current goes up, heats up the chip, chip turns off. chip cools. repeat cycle
12-12-23, 06:56 AM
#3
I thought those USBs were just for streaming and navigation and not for charging since the output is only 0.5 amps. So it was charging the phone to 100% fine up until this point?
I doubt it's a blown fuse because that would mean it would not have power going to it at all. Any signs of water damage? I've heard some cars have leaky cup holders and water could have gotten to the electronics.
I doubt it's a blown fuse because that would mean it would not have power going to it at all. Any signs of water damage? I've heard some cars have leaky cup holders and water could have gotten to the electronics.
12-17-23, 08:21 AM
#4
Get a can of computer keyboard compressed air. And blown out the dirt in the USB. Then if it's still acting up. With a small brush. Clean with electrical contact cleaner.
12-31-23, 01:35 PM
#5
Driver School Candidate
One of the front USB ports in our new 2023 does not work for CarPlay or charging
We took delivery of a 2023 GX460 about two weeks ago. This is our first Lexus, and I like the car a lot. My last car had built-in wireless CarPlay, so I'm now getting used to using a cable again.
In the front USB ports, only the lower USB port seems to work to charge or connect to CarPlay. When I connect to the upper port, the phone repeatedly makes the charging sound/shows charging...and then does it again a second later and so on. On the GX460's touchscreen, it will briefly show a message of "Device no response."
Other details:
I'm assuming both ports should work for CarPlay/charging, right? Does anyone else ever see this? I searched the forum and found posts about both ports/aux not working (e.g., a fuse or part problem). But my issue is just one port. And apparently just an iPhone/CarPlay issue.
Thanks in advance if you have any info, or could confirm this behavior is expected/unexpected.
In the front USB ports, only the lower USB port seems to work to charge or connect to CarPlay. When I connect to the upper port, the phone repeatedly makes the charging sound/shows charging...and then does it again a second later and so on. On the GX460's touchscreen, it will briefly show a message of "Device no response."
Other details:
- I've tried the included Lexus USB accessory cables, the Apple-recommended USB-A to USB-C cable from the Apple Store (a Belkin PowerBoost cable), a Porsche-brand accessory USB cable, and an Anker cable (I'm spending a lot of money on cables to troubleshoot this!)
- I have tried three different iPhones (iPhone 15 Pro Max and two iPhone 15s)
- Weirdly, I connected a Google Pixel 7 phone, and it seemed to connect right away with Android Auto in the same upper USB port (?!?!)
I'm assuming both ports should work for CarPlay/charging, right? Does anyone else ever see this? I searched the forum and found posts about both ports/aux not working (e.g., a fuse or part problem). But my issue is just one port. And apparently just an iPhone/CarPlay issue.
Thanks in advance if you have any info, or could confirm this behavior is expected/unexpected.
The following users liked this post:
TN57 (01-01-24)
01-01-24, 01:24 AM
#6
We took delivery of a 2023 GX460 about two weeks ago. This is our first Lexus, and I like the car a lot. My last car had built-in wireless CarPlay, so I'm now getting used to using a cable again.
In the front USB ports, only the lower USB port seems to work to charge or connect to CarPlay. When I connect to the upper port, the phone repeatedly makes the charging sound/shows charging...and then does it again a second later and so on. On the GX460's touchscreen, it will briefly show a message of "Device no response."
Other details:
I'm assuming both ports should work for CarPlay/charging, right? Does anyone else ever see this? I searched the forum and found posts about both ports/aux not working (e.g., a fuse or part problem). But my issue is just one port. And apparently just an iPhone/CarPlay issue.
Thanks in advance if you have any info, or could confirm this behavior is expected/unexpected.
In the front USB ports, only the lower USB port seems to work to charge or connect to CarPlay. When I connect to the upper port, the phone repeatedly makes the charging sound/shows charging...and then does it again a second later and so on. On the GX460's touchscreen, it will briefly show a message of "Device no response."
Other details:
- I've tried the included Lexus USB accessory cables, the Apple-recommended USB-A to USB-C cable from the Apple Store (a Belkin PowerBoost cable), a Porsche-brand accessory USB cable, and an Anker cable (I'm spending a lot of money on cables to troubleshoot this!)
- I have tried three different iPhones (iPhone 15 Pro Max and two iPhone 15s)
- Weirdly, I connected a Google Pixel 7 phone, and it seemed to connect right away with Android Auto in the same upper USB port (?!?!)
I'm assuming both ports should work for CarPlay/charging, right? Does anyone else ever see this? I searched the forum and found posts about both ports/aux not working (e.g., a fuse or part problem). But my issue is just one port. And apparently just an iPhone/CarPlay issue.
Thanks in advance if you have any info, or could confirm this behavior is expected/unexpected.
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pllxs (01-01-24)
01-01-24, 06:10 AM
#7
Same issue on my 23…I forgot about it until this post. Taking it in for service in 2 weeks, I’ll add it to the list.
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01-01-24, 08:23 AM
#8
Pit Crew
Do you guys have anything else plugged into the lower port when you are trying the top/front one? According to the manual, only one of the ports at a time will support AA/Carplay, and the other port becomes charge-only when AA/Carplay is active.
FWIW, I'm an AA guy with a Motorola wireless AA device plugged into the lower (back) USB port, and it works perfectly. I have a USB stick with music plugged into the other port, but it's invisible with the AA adapter in the lower port, as expected.
Mark
FWIW, I'm an AA guy with a Motorola wireless AA device plugged into the lower (back) USB port, and it works perfectly. I have a USB stick with music plugged into the other port, but it's invisible with the AA adapter in the lower port, as expected.
Mark
01-01-24, 08:52 AM
#9
Driver School Candidate
Do you guys have anything else plugged into the lower port when you are trying the top/front one? According to the manual, only one of the ports at a time will support AA/Carplay, and the other port becomes charge-only when AA/Carplay is active.
FWIW, I'm an AA guy with a Motorola wireless AA device plugged into the lower (back) USB port, and it works perfectly. I have a USB stick with music plugged into the other port, but it's invisible with the AA adapter in the lower port, as expected.
Mark
FWIW, I'm an AA guy with a Motorola wireless AA device plugged into the lower (back) USB port, and it works perfectly. I have a USB stick with music plugged into the other port, but it's invisible with the AA adapter in the lower port, as expected.
Mark
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pllxs (01-01-24)
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pllxs (01-03-24)
01-04-24, 02:31 PM
#13
Driver School Candidate
In a weird way, I kind of feel better. I thought my particular car was broken, but maybe this is more systemic ("works as designed"?).
01-04-24, 06:17 PM
#14
FWIW, there is some weasel wording in the manual (p. 446) about how the usb ports might not work with every phone, and might occasionally stop and start charging. I haven’t brought mine in for service yet, but I’m hoping I don’t have to fight with the dealer about it.