eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Brand New Pi4B Failing to boot (2 ACT blinks)

Sat Nov 16, 2019 9:59 pm

Hi,
I've received in August a brand new Pi4B 4GB from Canakit (My mother bring it to me from Canada but now it's in Brazil) since it arrived I was not able to boot it, every time I power it everything I got is a double blink on ACT LED and a solid Red power LED and no signal on HDMI or UART. Have tried everything I've found on the Stick post to solve the problem, some of it:

- Use different SD Cards Brands and Sizes (I've tested them on my 3B and ZeroW after and they work)
- I've dowloaded the latested Noob
- I've tried to Flash Raspian using Both Linux and Windows machines
- I've tried to replace the bootloader using a lot of different SD cards
- I've tested different power supplies including the Canakit one I bought with the Pi4B

Connecting the PI using USB cable to my Noteboot Windows recognizes the BCM SoC correctly (So it is for sure partially alive)


The issue is exacly the same some guys reported on https://www.raspberrypi.org/forums/view ... p?t=244283 so I think I'm not the only luck one to receive a faulty hardware.

It really looks like a HW issue although I was not able to replace it. Can someone help me fixing it?

-

drgeoff
Posts: 9915
Joined: Wed Jan 25, 2012 6:39 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Sun Nov 17, 2019 12:10 am

With no SD card inserted do you get the 4 blinks as described in the "not booting" sticky thread?

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Sun Nov 17, 2019 2:47 am

No, always 2 blink, doesn't matter if SD card is inserted or not. Bootloader reprogram procedure also didn't fixed the problem.

hitsware
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Location: sacramento , california , usa
Contact: Website

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Sun Nov 17, 2019 3:00 am

Try ' safe mode '
In config.txt

Setting hdmi_safe to 1 will lead to "safe mode" settings being used to try to boot with maximum HDMI compatibility.

In case you're booting but have no video.
( my same new unit only works in ' safe mode ' )

drgeoff
Posts: 9915
Joined: Wed Jan 25, 2012 6:39 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Sun Nov 17, 2019 9:33 am

hitsware wrote:
Sun Nov 17, 2019 3:00 am
Try ' safe mode '
In config.txt

Setting hdmi_safe to 1 will lead to "safe mode" settings being used to try to boot with maximum HDMI compatibility.

In case you're booting but have no video.
( my same new unit only works in ' safe mode ' )
That's irrelevant as the RPi isn't reading the card.

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Sun Nov 17, 2019 1:03 pm

drgeoff wrote:
Sun Nov 17, 2019 9:33 am
hitsware wrote:
Sun Nov 17, 2019 3:00 am
Try ' safe mode '
In config.txt

Setting hdmi_safe to 1 will lead to "safe mode" settings being used to try to boot with maximum HDMI compatibility.

In case you're booting but have no video.
( my same new unit only works in ' safe mode ' )
That's irrelevant as the RPi isn't reading the card.
Safe mode doesn't work, I have already tried it. As was said SD card doesn't seen to be read.

pcmanbob
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Joined: Fri May 31, 2013 9:28 pm
Location: Mansfield UK

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Sun Nov 17, 2019 2:38 pm

As the pi does not attempt to read the SD card ( 4 flashes with no SD card ) and you have not been able to reload the bootloader,
it suggests its a faulty pi or a fault in the SD card slot, can you see any damage in the SD card slot ?

replacement may be your only option...
We want information… information… information........................no information no help
The use of crystal balls & mind reading are not supported

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Sun Nov 17, 2019 3:28 pm

pcmanbob wrote:
Sun Nov 17, 2019 2:38 pm
As the pi does not attempt to read the SD card ( 4 flashes with no SD card ) and you have not been able to reload the bootloader,
it suggests its a faulty pi or a fault in the SD card slot, can you see any damage in the SD card slot ?

replacement may be your only option...
I can't see any damage in the SD card slot. Replacement is not an option now because sending it back to Canada cost the price of Pi.

Couldn't find the full schematics of Pi, is it available? I have access to scope but debugging this kind of problem without full schematics is difficult.

pcmanbob
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Location: Mansfield UK

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Sun Nov 17, 2019 3:35 pm

eendler wrote:
Sun Nov 17, 2019 3:28 pm

Couldn't find the full schematics of Pi, is it available?
I don't think full schematics have ever been published, repair is unlikely to be possible.
We want information… information… information........................no information no help
The use of crystal balls & mind reading are not supported

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Sun Nov 17, 2019 5:22 pm

I've found only a 1 page simplified schematics showing only external interfaces page. I will keep trying to fix it even without full schematics.

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Mon Nov 18, 2019 11:05 am

My Pi behaves just like in the video in the link below:

https://photos.app.goo.gl/3aP7id4fMhHCj3Cx9

This is not my video, user Kagekowai posted it in other thread in July. In the same thread another guy describes the same issue so I'm not the only one who have received a factory faulty part.

Does someone know which component in the Board is the bootloader e2prom?

timg236
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Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Mon Nov 18, 2019 11:34 am

It doesn't look like an EEPROM failure, possibly a fault with the SD interface. The initial very short single LED blink is just the power initialisation and not software

If you have a USB serial cable then you could try setting BOOT_UART=1 to get boot diagnostics.
https://www.raspberrypi.org/documentati ... _config.md

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Mon Nov 18, 2019 12:53 pm

timg236 wrote:
Mon Nov 18, 2019 11:34 am
It doesn't look like an EEPROM failure, possibly a fault with the SD interface. The initial very short single LED blink is just the power initialisation and not software

If you have a USB serial cable then you could try setting BOOT_UART=1 to get boot diagnostics.
https://www.raspberrypi.org/documentati ... _config.md
Why don't you think it's a Bootloader failure? According to documentation act should blink 4 times without SD Card plugged in, since it's not blinking as expected I considering it's something prior or during bootloader read.

I'll borrow the UART cable with a friend and test it, probably tomorrow. Today I will try scope the UART TX signal to check for any activity.

timg236
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Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Mon Nov 18, 2019 1:00 pm

eendler wrote:
Mon Nov 18, 2019 12:53 pm
timg236 wrote:
Mon Nov 18, 2019 11:34 am
It doesn't look like an EEPROM failure, possibly a fault with the SD interface. The initial very short single LED blink is just the power initialisation and not software

If you have a USB serial cable then you could try setting BOOT_UART=1 to get boot diagnostics.
https://www.raspberrypi.org/documentati ... _config.md
Why don't you think it's a Bootloader failure? According to documentation act should blink 4 times without SD Card plugged in, since it's not blinking as expected I considering it's something prior or during bootloader read.

I'll borrow the UART cable with a friend and test it, probably tomorrow. Today I will try scope the UART TX signal to check for any activity.
If the SD-power supply was damaged then it could stop the ROM or EMMC from running. Two flashes is not an error code, the error patterns repeat forever

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Mon Nov 18, 2019 9:05 pm

timg236 wrote:
Mon Nov 18, 2019 1:00 pm
If the SD-power supply was damaged then it could stop the ROM or EMMC from running. Two flashes is not an error code, the error patterns repeat forever
I've measured SD Card voltage Pin 4 (VCC) and Pin (GND) and it's a stable 3V3 rail. Fore sure SD card voltage is there....

timg236
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Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Mon Nov 18, 2019 9:12 pm

eendler wrote:
Mon Nov 18, 2019 9:05 pm
timg236 wrote:
Mon Nov 18, 2019 1:00 pm
If the SD-power supply was damaged then it could stop the ROM or EMMC from running. Two flashes is not an error code, the error patterns repeat forever
I've measured SD Card voltage Pin 4 (VCC) and Pin (GND) and it's a stable 3V3 rail. Fore sure SD card voltage is there....
The ROM always runs recovery.bin on the SD card in preference to the EEPROM. The rescue image on the downloads page always prints UART output so a USB serial cable might be the next step. It’s just possible that the SD card has some quirk that the bootloader doesn’t like. Although we haven’t had any SD HC compatibility issues since launch.
Might be worth posting a high res photo of both sides of the board anyway

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Tue Nov 19, 2019 12:03 pm

Please see board pictures in the link below. I'll test the UART later today.

https://photos.app.goo.gl/esweXjpbzpepfG679

timg236
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Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Tue Nov 19, 2019 2:30 pm

I couldn't see anything obviously wrong in the photos. I think monitoring the UART TX with the rescue bootloader would be a good start.

https://static.raspberrypi.org/files/rp ... 0137ab.zip

Use blank FAT32 formatted SD-CARD. Strictly speaking this doesn't have to be blank/formatted SD-CARD but doing so rules out FAT corner / corruption issues which is why we normally recommend that.

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Tue Nov 19, 2019 9:44 pm

timg236 wrote:
Tue Nov 19, 2019 2:30 pm
I couldn't see anything obviously wrong in the photos. I think monitoring the UART TX with the rescue bootloader would be a good start.

https://static.raspberrypi.org/files/rp ... 0137ab.zip

Use blank FAT32 formatted SD-CARD. Strictly speaking this doesn't have to be blank/formatted SD-CARD but doing so rules out FAT corner / corruption issues which is why we normally recommend that.
I've just tried this! No Activity on UART is detected! I used an UART-USB Adapter to test and also scoped the signals and nothing is transmitted.

I've also used the scope to confirm the perception that ACT LED blink slower when SDcard is connected and I could confirm it. Without SD Card inserted the difference between the first blink (power connection) and the second blink is about 88ms, with SD Card inserted it is about 500ms. Probably the Processor is trying to access the SD-card...

It's very frustrating. A brand new board which does not work.

jamesh
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Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Wed Nov 20, 2019 7:55 am

eendler wrote:
Tue Nov 19, 2019 9:44 pm
timg236 wrote:
Tue Nov 19, 2019 2:30 pm
I couldn't see anything obviously wrong in the photos. I think monitoring the UART TX with the rescue bootloader would be a good start.

https://static.raspberrypi.org/files/rp ... 0137ab.zip

Use blank FAT32 formatted SD-CARD. Strictly speaking this doesn't have to be blank/formatted SD-CARD but doing so rules out FAT corner / corruption issues which is why we normally recommend that.
I've just tried this! No Activity on UART is detected! I used an UART-USB Adapter to test and also scoped the signals and nothing is transmitted.

I've also used the scope to confirm the perception that ACT LED blink slower when SDcard is connected and I could confirm it. Without SD Card inserted the difference between the first blink (power connection) and the second blink is about 88ms, with SD Card inserted it is about 500ms. Probably the Processor is trying to access the SD-card...

It's very frustrating. A brand new board which does not work.
Although unlikely, it is possible you have a dead board. Although they are tested at the factory, they can fail in transit. When you make them in the quantities we do, eventually even unlikely things can happen.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
“I think it’s wrong that only one company makes the game Monopoly.” – Steven Wright

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Wed Nov 20, 2019 12:46 pm

jamesh wrote:
Wed Nov 20, 2019 7:55 am
eendler wrote:
Tue Nov 19, 2019 9:44 pm
timg236 wrote:
Tue Nov 19, 2019 2:30 pm
I couldn't see anything obviously wrong in the photos. I think monitoring the UART TX with the rescue bootloader would be a good start.

https://static.raspberrypi.org/files/rp ... 0137ab.zip

Use blank FAT32 formatted SD-CARD. Strictly speaking this doesn't have to be blank/formatted SD-CARD but doing so rules out FAT corner / corruption issues which is why we normally recommend that.
I've just tried this! No Activity on UART is detected! I used an UART-USB Adapter to test and also scoped the signals and nothing is transmitted.

I've also used the scope to confirm the perception that ACT LED blink slower when SDcard is connected and I could confirm it. Without SD Card inserted the difference between the first blink (power connection) and the second blink is about 88ms, with SD Card inserted it is about 500ms. Probably the Processor is trying to access the SD-card...

It's very frustrating. A brand new board which does not work.
Although unlikely, it is possible you have a dead board. Although they are tested at the factory, they can fail in transit. When you make them in the quantities we do, eventually even unlikely things can happen.

Then I'm the luck guy who bought a very expensive paperweight ($55 + tax + delivery ~= $75).

By the way, Raspberry Pi packaging is very unsafe for transport. My Pi arrived inside a paper box (the original one) without any antistatic bag. Since the box is bigger than the board the PI is loose inside the box probably generating static which cause damage to the board during transport.

jamesh
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Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Wed Nov 20, 2019 1:56 pm

eendler wrote:
Wed Nov 20, 2019 12:46 pm
jamesh wrote:
Wed Nov 20, 2019 7:55 am
eendler wrote:
Tue Nov 19, 2019 9:44 pm


I've just tried this! No Activity on UART is detected! I used an UART-USB Adapter to test and also scoped the signals and nothing is transmitted.

I've also used the scope to confirm the perception that ACT LED blink slower when SDcard is connected and I could confirm it. Without SD Card inserted the difference between the first blink (power connection) and the second blink is about 88ms, with SD Card inserted it is about 500ms. Probably the Processor is trying to access the SD-card...

It's very frustrating. A brand new board which does not work.
Although unlikely, it is possible you have a dead board. Although they are tested at the factory, they can fail in transit. When you make them in the quantities we do, eventually even unlikely things can happen.

Then I'm the luck guy who bought a very expensive paperweight ($55 + tax + delivery ~= $75).

By the way, Raspberry Pi packaging is very unsafe for transport. My Pi arrived inside a paper box (the original one) without any antistatic bag. Since the box is bigger than the board the PI is loose inside the box probably generating static which cause damage to the board during transport.
The packaging is fine - Over 1M of the Pi4 sold and transported in that packaging (and over 10M over the whole model range). Yours is one of a very very few that have suffered, and that problem may not even have been caused in transit. The piece of cardboard inside or the bag itself is for antistatic protection purposes - no bag is needed. Almost certainly not a static problem from transport.

I think you need to return the Pi to whomsoever you purchased it from for replacement, it does sounds faulty.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed. Here's an example...
“I think it’s wrong that only one company makes the game Monopoly.” – Steven Wright

eendler
Posts: 13
Joined: Sat Nov 16, 2019 6:40 pm

Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Wed Nov 20, 2019 3:06 pm

jamesh wrote:
Wed Nov 20, 2019 1:56 pm
eendler wrote:
Wed Nov 20, 2019 12:46 pm
jamesh wrote:
Wed Nov 20, 2019 7:55 am


Although unlikely, it is possible you have a dead board. Although they are tested at the factory, they can fail in transit. When you make them in the quantities we do, eventually even unlikely things can happen.

Then I'm the luck guy who bought a very expensive paperweight ($55 + tax + delivery ~= $75).

By the way, Raspberry Pi packaging is very unsafe for transport. My Pi arrived inside a paper box (the original one) without any antistatic bag. Since the box is bigger than the board the PI is loose inside the box probably generating static which cause damage to the board during transport.
The packaging is fine - Over 1M of the Pi4 sold and transported in that packaging (and over 10M over the whole model range). Yours is one of a very very few that have suffered, and that problem may not even have been caused in transit. The piece of cardboard inside or the bag itself is for antistatic protection purposes - no bag is needed. Almost certainly not a static problem from transport.

I think you need to return the Pi to whomsoever you purchased it from for replacement, it does sounds faulty.
Sending it back to Canada would cost the same as a new Board. I would like to debug it but without guindance it doesn't look possible since full schematics is not public...

timg236
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Re: Brand New Pi4B Failing to boot (2 ACT blinks)

Fri Nov 22, 2019 10:14 am

@eendler Please could you contact [email protected] mentioning this thread and my username (timg236)

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