It sometimes plays up with the green and orange lights flashing alternately and the print halts. When re-started it ejects the paper and then the same happens again. Tried changing the black & colour ink tank/heads but this didn’t consistently cure the problem. Leaving it off for a while sometimes helped.

I suspect that this behaviour means it detects some component as over-heating or jamming.

This depends on the detail design of the printer. Printers with separate ink tanks are known to use much more ink than those which have combined ink/print head cartridges, as in the former the head has to last much longer and requires more cleaning to remove stray dust and air bubbles which might get into the system when the ink tanks are taken out. Separate tank designs have efficiencies around 50-60%, while combined cartridge designs have efficiencies up to around 95%.

So which is cheaper to run? There is no clear winner, as the higher cost of integral head/ink tank units balances out the greater efficiency, and the varying costs of manufacturer\’s recommended papers is a further factor..

What has happened is that the software has determined that sufficient head cleaning/purging has taken place to fill the waste ink absorber with waste ink.

[It also means that you have spent rather a lot of money on ink, and that you may have used the printer more than was altogether prudent for a home/small office machine.]

This problem can not be solved by the user. You must take or send it to a service centre, where a technician will remove the old ink absorber, clean up any internal ink mess (a job seemingly made much more difficult and messy if the customer has been using cheap non-original inks) and enter a reset code to clear the “ink absorber full” condition.

[With some printers, no internal cleaning at all was required, while others, when unpacked, were plastered inside and out with black waste ink, and had to be completely dismantled and the parts hosed down and air dried before re-assembly. We suspected that the use of cheap inks caused this by gumming up the absorbers, hence the bad attitude you may encounter in the repair shop if you use cheap inks.]

Admittedly many users find the “waste ink tank full” very annoying, and one has some sympathy with their point of view, but alternative solutions would add to the point-of-sale cost, or be more messy and generate undesirable household waste.

[No you can not solve the problem by making your own absorber, or washing out the old one. DIY or recycled absorbers don’t work. Nor is it wise to enter the reset code, even if you can get your hands on it , without having the clearly well-used printer serviced.]

There is more to getting good quality prints than putting some ink cartridges in the printer and grabbing a handful of paper. This is particularly important when printing photos. Manufacturers recommend that you use their original ink, that you use their brand of paper, or other recommended paper, and that you use the correct paper settings in the printer driver.

Now what does the last item mean?

(Find Paper Settings for your printer)

If you explore the settings in your printer driver (Start/Printers and faxes/right click on the relevant icon, find Properties). Somewhere in here under preferences, page Setup or suchlike you should find the paper settings, typically with a drop-down list of “Plain paper” followed by a lot of other varieties from the manufacturer’s recommended paper list.

If you don’t, or can’t, select the paper you are actually using, the print profile applied to the paper will be wrong and the results will be poor. Don’t assume that it doesn’t really matter – it does, and if you use the wrong kind of paper the results can look awful ( full of banding).

Horror story:

Customer got hold of some postcard-sized blanks intended for a wax-process portable photo printer, and tried to use them in an inkjet portable photo printer. Result: the ink would not dry, ran and smeared everywhere, and the printer had to be partly dismantled and cleaned.

That’s not all that can go wrong. Customers printing out large prints in an A4 or A3 borderless format complained bitterly that while most of the print was OK there was banding across the trailing inch. (They could have been even angrier if they had calculated the true cost of the bad prints.) To cut a long story short, the manufacturer said that the fault, which evidently occurred when the paper changed speed as it escaped from the main rollers and was expelled by the exit rollers, was minimised by using their recommended ink and paper and the correct paper profile settings. Which was largely true.

If the colour balance of the photo is clearly wrong, first perform a nozzle test

(typically launched from the printer Properties)

This should show if any nozzle group is missing or not printing fully (it helps if you know what a good pattern looks like)

Colour missing:

Check that ink tanks physically contain ink (ignore on-screen displays).

Perform head cleaning.

Colours wrong:

Check that ink tanks are in correct positions.

Discard cheap inks and fit the manufacturer\’s recommended inks.

Check that inks are of the correct type. Do NOT replace regular colours by “photo” colours just because you think this is a good idea. In some manufacturer’s systems the “photo” is a lighter colour used to give greater colour gamut in a 6-ink printer, and if you use a “photo” in a 4-ink printer, all you will achieve is to give your prints a severe hue error! This error turned up in the workshops surprisingly often.

So, if the print colour is wrong, it is usually an operator error of some sort.

If the head is partly blocked, one would suspect the customer’s choice of ink brand.

Of course it could be that the head is really faulty. It does occasionally happen even if original manufacturer’s inks are used. One sneaky head fault occasionally encountered was that a colour prints too pale - the colour bar in the nozzle test print looks perfectly formed but is actually too pale! This also occurs if an ink tank is running out.

Ink tank empty?

*Don’t pay much heed to the on-screen display. (See post - How does the on-screen ink level work?)

*Remove the tank from the printer. Can you see the ink level through transparent sides?

*If you can’t see the ink level through transparent sides, its weight might give a clue.

*Find a clean sheet of scrap paper, put it on a table and whack the paper smartly with the outlet end of the ink tank (plain tanks only, not the sort that include the print nozzles). IF the tank contains usable ink, a spatter of ink will appear on the paper, or, of it is a tri-colour tank, three spatter marks.

I’d like to explain why this is not such a good idea.

While bubble-jets are 1) remarkably cheap, and 2) as good at printing photos as any other kind of printer at any price, they are really best suited for low volume home/home office/ small office printing.

All too often, the cheap third-party (i.e. not the manufacturer’s own ink) cartridges cause head blockage and other problems. If you are running a small business, this is the last thing you want. Time is money, and if you or your staff are struggling with a blocked print head it’s costing your business money. £25 for a dinky cartridge for a mobile printer may seem a rip-off - until a printer in one of your vans fails and is out of action for the day, and then the printer head can’t be cleared and the printer has to be sent out for service.

If you balk at the cost of bubble-jet printing with genuine inks (and let’s not fool ourselves, it IS expensive) there are alternatives:

Some manufacturers offer “value packs” of ink tanks and photo paper which offer significant savings.

If monochrome print will do, a dedicated monochrome printer will be far cheaper to run.

If you can wait, a photo printing centre will be far cheaper, and quite good enough for holiday snaps.

If you are printing colour leaflets and the like, there are a whole range of colour lasers that become cheaper to own and use than a bubblejet at quite low volumes.

If you want to print lots of glossy photo posters in A3, check out digital colour copiers - they cost a lot, but for speed and finish kick bubblejets out of the office window. These also illustrate the difference between a so/ho printer and a professional colour laser printer, the latter sometimes having four toner vats each the size of a 400g loaf or larger.

Don’t be like the guy who used a bubblejet printer till the mechanics wore out at over 50,000 copies. The ink tanks he got through must have cost more than a car.

Don’t be like the poor old guy who was given a bottom-of-the-range bubble jet, and used it for his hobby, which was to print A3 photos of aeroplanes in flight. He kept complaining that the tri-colour ink tank only lasted for about 25 prints before the cyan ran out. Lots of blue sky, tiny ink volume. Right!

Hovever for the most interesting one we have to thank a most irate customer. He swapped a USB-connected printer for another one just back from repair and was most annoyed when it didn’t work. I had to explain to him that while you can do a straight swap with some makes of printer, with Canon printers you can’t, as they all have unique USB identities. So you have to install the swap-out replacement as another printer, and when you take off the swap-out and re-fit the repaired printer, you have to set the printer you just connected to be the active printer.

Bubblejet printers are particularly fussy, as they won’t work at all without a driver, and they won’t work properly (or at all) without the driver for the exact printer model.

Printers with parallel ports may work using a driver for a slightly different model in the manufacturer’s range – but you may get strange looking print.

USB printers should not be expected to work at all unless the correct driver is installed. They are also known to refuse to work if the logic board is set for the wrong “region” - this requires a different region’s driver!

Drivers can in general be downloaded from the download section of the manufacturer’s website – easy if you have broadband, a problem if you don’t! Make sure you get the right one for your operating system. Windows drivers should not be a problem, but Linux or Mac drivers may be non-existent.

Installing a driver on Windows XP is really easy - not so on Windows 98 where some persistence and attention to the user instructions is/was often required. Unsurprisingly, some newer models of printer won’t install on Windows 98 at all, so if your venerable printer packs up it may force a general upgrade.

We found in the repair workshop that multiple installations one one PC of multi-part machines such as printer/faxes could be a severe source of grief… best avoid.

Please note that, if you use the manufacturer’s own inks and print from the printer several times a month, you should, hopefully, rarely have to initiate the printer’s self-clean, and should not have to resort to solvent cleaning of the heads at all.

Most of the Canon bubblejet printers has two levels of head cleaning available in the printer management software - normal and deep. If you see a problem, try the normal cleaning, and if that doesn’t do much, try the deep clean. If that doesn’t make a rapid improvement, it is better to give up rather than keep trying, as on each attempt you are using up rather a lot of expensive ink. Some blockages are too stubborn to be shifted by the printer’s self-clean and require sterner measures.

Canon printers generally have heads that can be removed by the user without the use of tools. If your printer has a different design and the print head cannot be easily removed, you may have to try wedging a pad soaked in solvent under the head. With the head removed, it’s a simple matter to stand the nozzle surface of the head in a puddle of solvent for an hour or so. Then wipe off the mess, reassemble the head and inks into the printer and run the self-clean.

Do NOT try using an ultrasonic bath to clean a printhead. (We tried this in the workshop, and it wrecked the print nozzles, making the head unusable).

If you have a lot of trouble with blocked printheads, it could be because you are trying to “save money” by using cheaper substitute inks.

It will be a surprise to many users to be told that the printer doesn’t measure the ink level. The readout is the result of some clever software making an estimate of how much ink is remaining based on the amount of printing and purging done. And this guesstimate can get confused and be totally wrong.

(If you still think a £70 printer contains six electronic liquid level gauges, ask your auto dealer what the fuel gauge for your car costs to replace.)

So how does it work (and how can it go wrong)?

The software works with a sequence of events as follows:

(with free ink sensor)

Printer detects the insertion of an ink tank containing free liquid ink - software assumes it is 100% full.

Ink is used for printing or purging - software estimates the new ink level.

Printer detects that there is no longer any free ink in the tank. Software indicates that tank is low and needs changing soon.

A few pages can be printed with the ink in the internal absorber. Then the software signals “No ink” using a software counter.

Inktank is changed (or ink runs out).

(without free ink sensor)

User signals that a new ink tank has been fitted.

Ink is used for printing or purging - software estimates the new ink level.

Software indicates that tank is low and needs changing soon.

After a few pages, the software signals “No ink” using a software counter.

Inktank is changed (or ink runs out).

The system with free ink sensor works well enough to convince users that the printer contains several electronic liquid level gauges, which it almost certainly does not. This depends on the ink tanks being undisturbed. The removal and replacement of partly full tanks will confuse the software and invalidate the readouts.

If you are having an ink problem, don’t rely on an electronic readout. If the design of the printer permits, remove the ink tank and (assuming it is transparent) look at the ink level. If the tank is opaque, feel its weight or swap it for a full one.