Pi3 with a lightning bolt?

[Doug B]

When I started my Pi3 just now, I got a picture of a lightning bolt in the upper right corner of the screen. Could someone please tell me what that means?

Thanks

Doug Byfield

[RaTTuS]

can you post a picture

[6by9]

https://github.com/raspberrypi/firmware ... 52c4a6be83
firmware: arm_display: Add bitmapped icons for warning conditions

See: #367

It would have helped if you'd said you'd done an rpi-update (not recommended these days unless you need the absolute bleeding edge developments and are prepared for the occasional breakage)

[RaTTuS]

aha so power brownout

[6by9]

aha so power brownout

Probably, although I haven't done an rpi-update and looked myself, and the commit doesn't say.
It would be the most logical one out of under-voltage and over-temp (yellow or red).

[douglasby]

Thanks, 6x9, that link is quite useful.

Now that I think of it, I **DID** do a rpi-update on Raspian full version. I didn't know that it wasn't recommended.

BTW-the lightning bolt went away after 2-3 reboots. I was also using a RAV Power Pack battery:

https://www.modmypi.com/raspberry-pi/ac ... ?limit=100

https://github.com/raspberrypi/firmware ... 52c4a6be83
firmware: arm_display: Add bitmapped icons for warning conditions

See: #367

It would have helped if you'd said you'd done an rpi-update (not recommended these days unless you need the absolute bleeding edge developments and are prepared for the occasional breakage)

[cliveflint]

I just had some Anker cables delivered and the lightning symbol has disappeared.
Good quality cables make a difference.

[Douglas6]

Good quality cables make a difference.

Er, yes. There must be thousands of posts on this board to that effect.

[darksky]

I too see this for maybe 2-3 seconds when my RPi2 boots only. Could it be a false positive triggered by something in the boot process? I used stress to max out all CPUs (temp got up to 60C), yet I didn't see this icon again.

Code: Select all

stress --cpu 20 --io 20 --vm 6 --vm-bytes 25M --timeout 120s

[mahjongg]

I too see this for maybe 2-3 seconds when my RPi2 boots only. Could it be a false positive triggered by something in the boot process? I used stress to max out all CPUs (temp got up to 80C), yet I didn't see this icon again.

Code: Select all

stress --cpu 20 --io 20 --vm 6 --vm-bytes 25M --timeout 120s

no, its not a false trigger, the hardware simply detects a brownout at that point (where the GPU, not the CPU, is stressed fully for a short time). Just get a better micro USB cable if you want to keep safe, or simply ignore the problem at your own risk.

[darksky]

Thanks for the info. I have tried playing back videos where the GPU would be doing the decoding and cannot reproduce :/ Is there an artificial GPU stress I can run to see about replicating?

[FTrevorGowen]

I too see this for maybe 2-3 seconds when my RPi2 boots only. Could it be a false positive triggered by something in the boot process? I used stress to max out all CPUs (temp got up to 80C), yet I didn't see this icon again.

Code: Select all

stress --cpu 20 --io 20 --vm 6 --vm-bytes 25M --timeout 120s

no, its not a false trigger, the hardware simply detects a brownout at that point (where the GPU, not the CPU, is stressed fully for a short time). Just get a better micro USB cable if you want to keep safe, or simply ignore the problem at your own risk.

+1
Also note that @douglasby was using a powerbank - some can take a few seconds to settle down after the initial current surge during boot. (Something I observed when the low-voltage detection/warning system was introduced with the B+)
Trev.

[Texas-Mark]

I too see this for maybe 2-3 seconds when my RPi2 boots only. Could it be a false positive triggered by something in the boot process? I used stress to max out all CPUs (temp got up to 60C), yet I didn't see this icon again.

I see the same thing ONLY when the Pi is booting up. It happens even when booting just the PI with nothing attached. If I run it normally with a breakout cable and several sensors and even 3 backlit LCDs and a servo, I never get the symbol after boot (and I don't have it disabled either). I tried several power supplies including a 5.1V (adjustable) 4A one and I use the recommended Mediabridge cable (and have tried others), but it still comes up for a couple of seconds during boot. I just ignore it because I know there is nothing wrong with the power supply or cable. But still I am curious as to why it displays. I'm pretty sure it did not start doing it until a relatively recent Raspian update. I need to dig out my scope and take a look at the 5V line and see if it's doing anything when the symbol appears.

Edit - Got out my pocket scope and watched the 5V line (on the Pi) during boot up and it never dipped more than a few millivolts.

[krisvale]

I get this lightning bolt for a few seconds, once in a while.
The rpi2 is just sitting idle. Sometimes even with the display blacked out.
This really seems to be a false positive, I wonder if it is disableable?

[jamesh]

I get this lightning bolt for a few seconds, once in a while.
The rpi2 is just sitting idle. Sometimes even with the display blacked out.
This really seems to be a false positive, I wonder if it is disableable?

No, its not a false positive, but even when idle the Pi might be doing something (e.g. talking to a USB device) that increases power consumption slightly.

[jamesh]

I too see this for maybe 2-3 seconds when my RPi2 boots only. Could it be a false positive triggered by something in the boot process? I used stress to max out all CPUs (temp got up to 60C), yet I didn't see this icon again.

I see the same thing ONLY when the Pi is booting up. It happens even when booting just the PI with nothing attached. If I run it normally with a breakout cable and several sensors and even 3 backlit LCDs and a servo, I never get the symbol after boot (and I don't have it disabled either). I tried several power supplies including a 5.1V (adjustable) 4A one and I use the recommended Mediabridge cable (and have tried others), but it still comes up for a couple of seconds during boot. I just ignore it because I know there is nothing wrong with the power supply or cable. But still I am curious as to why it displays. I'm pretty sure it did not start doing it until a relatively recent Raspian update. I need to dig out my scope and take a look at the 5V line and see if it's doing anything when the symbol appears.

Edit - Got out my pocket scope and watched the 5V line (on the Pi) during boot up and it never dipped more than a few millivolts.

When it first starts up , the power requirements are a bit higher - all cores running at full tilt until governor kicks in (IIRC), all attached devices being started up etc. Might be enough to ping the detection.

[spoz]

I have the same issue, I get the lightning bolt symbol quite often on boot.

I have checked my power supply and it reads 5.21v the entire time, an the pi never draws more than 0.5A. I havent checked the ripple with an oscilloscope but I am using two good quality USB supplies and 0.5A is well within their spec (1A and 2A).

Considering the intended use/users, I consider it a design fault for there not to be any voltage regulation onboard. If short duration load spikes are such a common issue, how hard is it to add an input capacitor?

[texy]

Hi,
where are you measuring the voltage? On the Pi itself? That's where you'll need to measure it.

Texy

[spoz]

You are totally right. In between now and my last post I discovered the test points on the pi and did some probing. Turns out all of my USB cables are dropping 150-180mV. Though the input stage of the pi (current mirror and fuse) drops nearly 60mV.

Edit: So after the input stage at TP7, I am still getting 5.00v, and seeing the lightning bolt icon. Must be transients too fast for my meter.

Time to buy some shorter cables, or maybe make my own with some large gauge wire.

Thanks for the point in the right direction.

[i-Moi]

Hi everybody, I had the same problem myself, and I finally solved it by using a better and shorter cable. The lightning bolt symbol disappeared. Unfortunately, no temperature symbol has appeared, because the cable is so short it's too close to my other devices in a pretty little space, and therefore, temperature has risen up... does anyone has an idea about longer but still good quality cables ? Thanks !

[mahjongg]

No temperature symbol is good, it means your device is NOT overheating, I doubt it can overheat from a nearby cable as these certainly should not get hot.

[rpdom]

Should that read "Unfortunately, now temperature symbol has appeared"?

[Sioghi]

I'm having this issue using the official 7" touch display on my Pi3.

Powersupply delivers 2.4A, tried new shorter and thicker cables and different PSUs, without any improvement.

I did run upgrades. The lightning bolt is always there even when CPU is idle.

I havent tried a plain installation yet as it requires disassembly to access the sdcard. Poor design or the official touchscreen housing imo. Furthermore I had to rotate the display because of the manufacturing flaw.

Any advice is welcome.

Best regards

[jamesh]

Hmm. I don't see that issue with similar setup. Might be worth starting a new thread in the display section.

[davidcoton]

My touchscreen and B+ combo needs two cables and a supply with dual output to avoid undervoltage issues.