Troubleshooting: so easy a ten-year-old can do it

The ten-year-old in question is Jessica, Gordon’s daughter, who dropped into the office last week to give us a hand testing some Raspberry Pis that customers had sent back to the manufacturers as “faulty”. Whenever this happens, the Pis are passed on to us or to the Sony factory in Wales where the Pis are built, and we test them to find out what’s going on and to ensure that there isn’t a bug in manufacturing.

At the moment, we see returns in the order of about 0.02% of all units (the ones Jessica is working on are on the right of her desk). The factory processes are always being refined, and we hope to see this number come down even further as all of our production transitions to the UK. As usually happens when we troubleshoot returns, though, we found that around half of Jessica’s Pis weren’t faulty at all. We can’t emphasise this enough: before you decide you’ve got a broken unit, check out the troubleshooting forum and the wiki. If your Pi doesn’t work, the first check you should make is that the power supply you’re using is a branded, reliable 5v supply. Many no-name supplies (especially in the US, for some reason) do not actually provide the voltage that they claim to, and that’s been causing all kinds of problems.

Jessica finds another working Pi. Later, we’re sending her up that ladder to clean out the asbestos tube.

You should also ensure that you’re running the latest version of Raspbian. (Lorna just mailed me this morning with another handful of emails from a group of people swearing blind their Pis are broken. They weren’t. The people in question were using SD cards with an out-of-date image that they’d bought from a third-party vendor, that didn’t work with the newer chipset on their Raspberry Pis.) If you aren’t sure about your SD card image, see this post from March. Pre-flashed cards from third party dealers on Amazon or eBay are a bit of crapshoot, and they’re something we can’t police; if you need one, get your pre-flashed card from one the companies we licence to sell the Pi itself. (See the top right of the page.) Several of Jessica’s test cases had been sent back to Farnell and RS because of this issue, and while that’s great for Jessica, it’s really frustrating for the customer who ends up without a Pi for a week and who will probably find their next Pi has the same problem, because they’re using the same card. (I am aware of one person who sent SIX Raspberry Pis back to Farnell one after the other, insisting that they were all broken, that we/Farnell were charlatans, etc. etc. In the end it turned out that he hadn’t actually flashed the SD card at all. This is an extreme case.)

We did make sure that Jessica was rewarded for all her hard work: this is what we were doing on Monday.

Thanks Jessica!


Jason Bramwell avatar

What happens to the Pi’s that are proven to be working ok? Are these returned to Farnell for re-sale or used elsewhere?

William Discourse avatar

She gets to keep them as dolls.

liz avatar

Jessica is *really* not a dolls sort of person.

Nicole avatar

And I’m thankful for that!

liz avatar

We use them internally, we use some as loaner units for press, exhibitions and so forth, and we use them as freebies in very special circumstances. (Very special: as in, if you ask for one, we almost certainly won’t give you one.)

Kevvy Wilch avatar

Aw, go on please?

Steve Smith (G0TDJ) avatar

This is what we need, more young people getting interested in tech!

Well done Jessica.

Simon Faulkner avatar

Jessica, Have you got your Amateur Radio License yet?

I think you might enjoy it :-)

Simon M0TGT

Norman Dunbar avatar

Can I have Jessica’s job when she’s finished with it please? ;-)


Andy avatar

I want it too!

Ivan avatar

Me too! i’m only like 12!

JamesH avatar

Is that sunny Hunstanton?

liz avatar

Nope! It’s sunny Reach.

Sniper435 avatar

It certainly was sunny this year :D
a nice change from last years cold and rainy affair.

on another note – Go Jessica :)

andrum99 avatar

I think it would be helpful if you created an official troubleshooting page with at least these two issues, namely duff power supplies and needing to use the latest raspbian image that supports the hynix RAM. I know there are third party FAQs and troubleshooting pages, but I think it needs more prominent exposure on the main website, i.e. this one.



liz avatar

There’s information in the box for each Pi which directs people straight to the downloads page, and tells them about the forum, which is where we deal with troubleshooting.

andrum99 avatar

I forgot about the bit of paper in the box. I remember seeing that now that you mention it. I don’t think providing a page listing the usual “gotchas” is asking too much. You could also add stuff to the bit of paper that is included in the box with each one. In my view this would make very good business sense. Obviously it would not prevent every return of working Pi’s but it is cheap to do and would reduce returns.



balooba avatar

No. The Pi is about YOU finding stuff out, not about an end-user-safe product. Buy a Windows PC.

Michael Hawksworth avatar

Have to agree with Andrew. You should have a HELP menu option up there and something on screen.

Even if it only takes you to the top 5 causes and links to other resources it would make it far more friendly for people not happy tinkering with tech.

Jim Manley avatar

Even if it were somehow possible to prominently silk-screen the warnings on the Pi board in 72-point typeface, there would still be the same number of returns. As a corollary to P.T. Barnum’s truism that there’s a sucker born every minute, there are 10 in-DUH-viduals born for each of those suckers who have been coddled to the point of not being able to follow instructions on their own.

hamjudo avatar

You are so pessimistic. I think it might cut the rate of returns by as much as 5 percent. Instead of getting 200 returns per million shipped, it might drop it down to 190 returns per million shipped. Represented another way, the return rate might drop from 0.020% to 0.019%. (Math is Fun! A 5% drop in rate of returns, is a 0.001% drop in the return rate.)

If returns cost about as much as a unit does, eliminating those 10 returns, would represent $350 saved. Unfortunately, ink is not free, and 72 pt type takes a lot of ink. The savings just go away completely, if the per unit cost of the ink exceeds $0.00035. It gets much worse if you think of the cost of changing the manufacturing process, and/or the equipment to apply the ink.

On a more serious note. 0.02% returns is a phenomenally good rate, and you should be quite proud.

Jim Manley avatar

With all of the things that are so easy to do that a 10 year-old can do them, I keep within shouting distance of some at all times (it helps to be teaching in a school ;) ). They can even solve the flashing 12:00 on a VCR after the power goes out (little show-offs), and yes, they can do it without the remote control, which they can later find deep in the sleeper-sofa upstairs using some sort of in-bred nerd RF detection ability. Don’t even ask why there is a VCR in proximity unless you haven’t taught in a modern classroom such as mine … built in 1955 … by the Army! Yes, the VCR is painted in many layers of thick, white enamel because it doesn’t respond to saluting (on a military base, so the advice to new recruits goes, “If it moves, salute it, and if not, paint it.”).

Anyone who doubts the existence of evolution only needs to hang around some 10 year-olds for a few minutes to realize they are a completely different species from us old fogies! Go Jessica! :D

Juan avatar

Would be good if they were made available to buy as a used unit.


Otto Schreibke avatar

(Treading on very thin ice) Children? Only if fitted with an “Off” switch. ;-)

Ken MacIver avatar

Well done Jessica;

I’ve been tying to convince my boss we should go here

as our after work playground….

Richard Collins avatar

I feel your pain. I’m doing an OU degree and one chap posted a rant about how the course material was not up to scratch and how it was falling below legal standards, although was never sure what he meant by that. He posted a screen shot of a command that he said did not work even though he ” had followed the instructions to the letter “.

You know what’s coming, the screen shot showed he had miss typed the command substituting cron with corn. LoL

Sad thing, not an isolated case.

ColinD avatar

But it is an interesting point: people expect things to “just work”. Press the on button on your iPad and on it comes etc.

Now don’t get me wrong, I think the Foundation’s approach of making downloads available for the OS that are written to the SD card by oneself is a Great Thing (TM). It teaches the user from day one a bit about the “behind the scenes” world of what makes a computer work. And for others it does not mean some fancy jailbreak or similar is required just to use the hardware for a non-“official” purpose.

However if someone is taking their first steps into the land of Pi (or similar, QED: the OU course you mention) then the shock of finding out that more than the On button is needed to get up and running can be quite a jolt: almost as jarring as having the heating fail and the shower reboot to safe mode (read: “cold, very cold”). Getting over that initial bump can be quite frustrating and can lead to emotions running high: “why doesn’t it JUST WORK!”

I think buying a pre-installed SD card from the interwebs is therefore very appealing even if they are then the cause of the user’s woes. Take my own non-SD example: until recently (ie: less than a week ago) I wouldn’t touch a soldering iron. That’s WAY too complex, WAY too much like not having an On button (literally: had to solder one). I would always describe myself as “the software guy”. If a circuit board was pre-soldered (eg: a graphics card) then I’d happily use it, if not then I wouldn’t touch. But with support and encouragement from the wonderful Raspberry Pi community I soldered my first board together a few days ago and now I have a working LCD clock on my desk. Now I won’t claim it’s the best soldered thing in the world and I think there’s a loose connection somewhere I need to trace as it works a bit intermittently, but the point is that having got over that speed bump suddenly soldering doesn’t seem scary at all.

Same with getting the Pi up and running: once they’re over that initial no On button bump then suddenly using the Pi is as easy as its namesake.

ukscone avatar

looks like slave labour to me :)

liz avatar

No no – that’s what Rob is for.

Marc avatar

But is not child labour against the law?

Andy avatar

Jessica isn’t getting paid, so it perfectly legal… I still want her job.

liz avatar

She was *kind of* getting paid, but only in tilting and whirling and getting to watch me get really, really nauseous.

AndrewS avatar

I guess it’s a great head-start to Jessica’s CV too!

CVBruce avatar

I don’t know if this exists, so pardon my ignorance if it does.

Is there a tool for Windows, Mac, etc. that can do some sort of CRC or MD5 checksum on the SD card? I know you give the checksums for the OS images, but after you flash the SD card, there should be a tool to verify that the card has a valid image, as well as the version of the image. Might save some returns.

breaker avatar

Hmm, nice idea, but I have a feeling there may be elements of an SD card that could vary the checksum from card to card, but then again maybe not. Also, even if a checksum is OK, that doesn’t mean the SD card works OK with the RPi.

AndrewS avatar

I thought this was an interesting idea, so I put together a command-line proof-of-concept using Python and raw-device-access under Linux – was a fun little project :-)
It works great for freshly-written cards (it can auto-identify any version of squeeze/wheezy/raspbian), but as soon as you boot up the Raspi with the card inserted, it modifies files on the card, which of course alters the checksum. And even just putting a freshly-written card into a card-reader on Windows (so that the ‘boot’ partition appears) seems to change parts of the filesystem (I’m guessing last-access timestamps?), which again ‘breaks’ the checksum :-(

So, nice idea but unfortunately unworkable!
People would get very confused if just removing and re-inserting the SD card would cause their checksum to change from ‘good’ to ‘bad’.

mperrin avatar

Those who may be wondering if their problems are power related might find my post Powering the Pi – Current and Voltage Restrictions and the subsequent comments by others to be useful.

Alec avatar

FWIW I recently returned a brand new model B (made in China). It did not boot w/ an SD which worked with an earlier Pi that I had. (Even with repeated attempts.) Neither did its replacement – but the latter did work, however, with the use of a diifferent SD.

liz avatar

Yeah – sounds like your original Pi wasn’t broken. See

don isenstadt avatar

I just downloaded the archlinux distro from 2-13 from the raspberrypi site… it will not boot on rev2 512mb but works ok on the 256 model a .. I would suggest a refresh..yes?

Seth avatar

You say the Sony factory is in Wales, but mine says “made in China” on it. Does Allied Electronics manufacture them elsewhere?

ukscone avatar

Allied is part/associated with RS who still make some in China

Seth avatar

I have done some research and realized that RPIs are not manufactured, but belched out by the Red Dragon. Unfortunately, RS has another dragon in captivity in China, and forces it make RPIs, but this time with the FCC mark on them.


liz avatar

RS are in the process of transitioning all their manufacture except for that for the far east market to the factory we’re already using in Wales (they’re already making the majority of their Pis there).

Arthulier avatar

“Jessica finds another working Pi. Later, we’re sending her up that ladder to clean out the asbestos tube.”

That’s not even funny to joke about – you should be taking the safety of children much more seriously.
A mini scaffold would afford much better support, and allow both hands to be used for cleaning purposes.

john avatar

Lawyers will be arriving shortly!

Jim Manley avatar

What were the lyrics to that Joni Mitchell song? Ohhhh, yeahhh, “Send in the clowns … don’t bother, they’re here … ” :D

Slim avatar

Oh Good grief! Lighten up .

tai viinikka avatar

I was about to jump all over you, but then I had to burst out laughing.

PJC avatar

I am curious. What types of issues are you seeing with the 0.02% of returned pis that are not working properly, and what is your failure mode analysis showing; were they defective from the factory, damaged in shipping, damaged by the customer, etc.? It would be good to know when offering help to users on the forums.

Harold Fieger avatar

Just fyi
in reply to getting your sd card from one of the “approved dealers in the upper right”, I bought my PI from
Element 14 along with an unbootable SD card. ;-)

JBeale avatar

“Many no-name supplies (especially in the US, for some reason) do not actually provide the voltage that they claim to”
One factor might be US mains power is 110 Vac instead of 220. The switcher circuit is ‘nominally’ capable of handling this, but on the cheap end, maybe not really? Still fine for a cell phone, it just charges more slowly, but not good for R-Pi.

Kevvy Wilch avatar

but surely David Moyes about to be Man Utd manager is far more interesting?

The Other Peter Green avatar

> David Moyes
> Man Utd

Homer Hazel avatar

I notice she is being ably assisted by the Raspberry Pi Bear whose name I have already forgotten. Well done. Are those for sale anyplace? I just supported another project for Raspberry Pi on kickstarter. This one a Lego robot interface.

Potted Avocado avatar

Teh bear is Babbage, isn’t it?

liz avatar

It certainly is.

liz avatar

They will be shortly; we’re gathering stock for the new store at the moment.

Slim avatar

Sadly the world is full of know-alls like the moron who hadn’t even loaded the SD card with Raspian before trying to boot.
Just when you make something fool-proof, Mother nature goes and invents a better fool and then puts him in to the world to tick off the rest of us! :-)

mccp avatar

“A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.”

Douglas Adams

Gert van Loo avatar

Against stupidity even
the gods contend in vain!

Martin Angove avatar

I am aware of one person who sent SIX Raspberry Pis back to Farnell one after the other, insisting that they were all broken, that we/Farnell were charlatans, etc. etc. In the end it turned out that he hadn’t actually flashed the SD card at all

Many years ago I seem to remember one of the Acorn magazines which sold kits of hardware for the projects they featured (may even have been Mike Cook) complaining that they’d had a bit of a shouting match from a customer because a kit wouldn’t work, only to find out that he’d superglued the components on rather than soldering…

And people look at me oddly when I spend a few minutes reading the manual before plugging any new purchase together…

Mark avatar


Doesn’t your post indicate the need for an official “complete” raspberry pi kit to be the default that is sold to Joe Public? Something that includes an authorised power supply and a proper SD card ready to go?

As you’ve pointed-out there is a lot of scope for non-technical users to run into problems and therefore blame a perfectly functioning Pi, and you guys by extension.

Most non-technical people just need something they can buy and plug-in straightaway without resorting to having to buy dodgey equipment from eBay, Amazon et al.


Dr. Mouse avatar

“Most non-technical people just need something they can buy and plug-in straightaway”

I would suggest the Pi is not the right piece of equipment for these people. It’s there for tinkering. It’s not supposed to be a “does everything out of the box” package.

If someone can’t even read the simple instructions and write an SD card to boot off, they will kill the Pi quickly when they start tinkering. Tell them to go buy an iMac.

Paul avatar

iMac, don’t you mean an iPad?

Keyboards can be dangerous!

AndrewS avatar

Selling an official complete kit would obviously cost much more than the $25 tagline, and IMHO would probably generate a lot of negative PR for the Foundation.

If you do want such a ready-to-go kit, have a look at Maplin’s offering…

Marc avatar

a ROKU will work “out of the box” but will cost $75 – $100.

A raspi will require tinkering, which is why it is better. Also with all required components (KB, Mouse, PS, HDMI cable), the cost will be nearly the same.


The Other Peter Green avatar

In the early eighties I worked in the editorial department of an electronic hobbyist magazine (ETI if anyone remembers that). We published a project for a temperature-controlled soldering iron. Part of the circuit was obviously high-current, so the parts list specified 1mm square wire. I got a letter from a reader asking where he could buy square wire.

A more apocryphal story which pre-dated my time there was of the man who sent in a completed project complaining that it wasn’t working. Every component was in its correct place. Every component had its leads bent perfectly at 90 degrees and securely fixed to the PCB tracks.

With Araldite.

Gordon avatar

Yes we all remember ETI… In fact I spent many years trying to build many different projects from various bits and pieces!

Eben actually has a box full of them on his desk still!


Homer Hazel avatar

I apologize, but I do not know what 1mm square wire means, so I would probably ask where to get it also.

I am guessing that Araldite is a brand name of some sort of glue.

The Other Peter Green avatar

“1mm square” referred to the cross-sectional area – so, thick wire that would conduct a lot of current without melting.

Araldite is, indeed, an epoxy adhesive, so strong that it’s used to construct racing cars and aircraft wings. Conductive? Not so much… :-)

Homer Hazel avatar

Thank you. So it is like gauge as in 12 gauge wire.

I thought the other might be some sort of superglue, I never thought epoxy.

Wow, he must have been a wood worker in a previous life.

liz avatar

1mm² – and Araldite is the goddess of sticking together for the kids. (Joke.)

meltwater avatar

Big credit to the authors of the section, it is very comprehensive.

Also, if you spot something which is missing then try to update it, it will save someone (probably many others including Jessica) a lot of time and effort.

Rostislav LIBER avatar

“Later, we’re sending her up that ladder to clean out the asbestos tube.” It is really black humor according to this article:

Mr Logic avatar

The humour is indeed predicated by the inclusion of a dangerous material and a minor. The intimation that any person might be casually exposed to such a noxious substance without proper training and specialist equipment is so ludicrous that the resulting cognitive dissonance causes mild amusement in many people. The fact that that person is a child is a hyperbolic device that exponentially amplifies the throwaway jeopardy and therefore the humorous element.

In short, a classic case of black humour, albeit one that will not be enjoyed by all.

Mark Symons avatar

I think you hit the nail on the head there Mr. Logic!

…and just for the record, in case of humour confusion with my comment; no nail was hammered into anybody’s head :-)


john avatar

Wouldn’t that be “white” humor (ok, humour) in the case of asbestos?

Tom Dubick avatar

Well done Jessica.

I think the Raspberry Pi has two competing interests they must balance (flexibility vs accessibility).
The XBox 360 is very accessible, but it is not very flexible. You face barriers to modifying your XBox. I think the role of teachers and volunteers is to help young people with the accessibility issue and allow the kids the flexibility to learn and create at a higher level,
Tom Dubick

Peter avatar

Amazed by my first pi I bought a second one not from one of the listed online shops but from a reseller I trusted .. It never was as stable as the first one .. I couldn’t over clock it looked like a fine black dust was over the whole board. Not fair to send it back to a charity so …. I sprayed WD40 all over it …(LOADS) .. wiped it all off carefully .. left it to dry …. Now as good as my other pi … complete turn round … xP

Lorna avatar

Excellent work, Jessica!

Bob A. avatar

As a licences sparky I can’t let the question of the square cable go without some comment. Cable sizes are given in square millimetres. NOT millimetres square. And for good reason. Millimetres square infers a measurement of 1mm X 1mm, which in this case has a cross sectional are of 1 square millimetre. Now think about a cable measuring 2mm X 2mm. This could be called, and is in fact 2mm square, whereas its cross sectional area is 4 (2 X 2) square millimetres which gives it around twice the current carrying capacity. If you go up to 3mm it becomes 3 times. So the correct terminology is square millimetres not millimetres square.

Bob A. avatar

Damn iPad – that should be licensed electrician.

The Other Peter Green avatar

Your iPad auto-corrected “sparky” to “electrician”?? 0_o

:-) for the avoidance of doubt…

Wayne avatar

idea for future reference which might help lower the super low return rate…

put on corner of front of box “if having trouble, go to

and have the troubleshooting URL printed on the box!

i know it would be kind of idiot proof to do that before returning it and claiming its broken, but some people arent all there and need it even more idiot proof!

food for thought?

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