You're mid-print, the paper jams, and then the LCD flashes 5B00. Or maybe you just powered the printer on and it refuses to do anything but blink that code. This happens on Canon Pixma models like the MG3620, TS5020, and MG6820, especially after a few years of heavy use. The printer won't print, scan, or even acknowledge the ink cartridges. Yeah, it's infuriating—I've been there.
What Actually Causes 5B00
Inside every Canon inkjet is a small sponge-like pad that catches excess ink during cleaning cycles and borderless printing. Over time, that pad soaks up ink until it hits a saturation point. The printer tracks this with a counter, and when it crosses a threshold, it locks down with error 5B00. It's a safety thing—soaked pads can leak into the printer's guts.
The annoying part: the counter is software, and the pad might still have a little room. But Canon doesn't give you a menu option to reset it. You need the service tool, and I'll walk you through it.
The Fix: Reset with the Canon Service Tool
This is the only reliable way to clear 5B00 without replacing the pad right away. You'll need a Windows PC (the tool doesn't work on Mac), a USB cable, and a few minutes. I prefer the STV510 or STV511 versions—they support most Pixma models. Here's the step-by-step.
- Download the service tool. Search for "Canon service tool STV511" from a reputable source. It's not on Canon's site—they don't want you reseting this. But it's out there.
- Install the tool. Unzip the folder, run the .exe as administrator. If Windows blocks it, right-click > Properties > Unblock, then run again.
- Put the printer in Service Mode. This is the trickiest part. Turn the printer off. Hold the Stop button (the red triangle), then press and hold the Power button while still holding Stop. Keep both held for a few seconds, then release Power but keep holding Stop. Wait for the green LED to blink, then release Stop. The printer might whirr—that's normal.
- Connect the printer via USB. Use a real USB cable, not a hub. Windows should detect it as a generic device.
- Open the service tool. Click on the port drop-down and select your printer's USB port. If you don't see it, you missed Service Mode—repeat step 3.
- Click "Set". In the "Printer" section, click the "Set" button next to the model name. It'll verify the connection.
- Go to the "Cleaning" tab. Then click "Waste ink counter" and "Set" (not "Clear" yet). You'll see a number like 100% or a hex value. That's the saturation.
- Set the counter to 0%. In the same window, click the radio button for "0%" or "Main" and then "Set". The tool will write the reset.
- Click "Clear" on the waste ink counter. Some versions need this to finalize. The tool will confirm.
- Turn off the printer (use the power button), wait 10 seconds, then turn it back on. The 5B00 should be gone.
That's it. If the tool says "Communication error" or "Unknown device," you're not in Service Mode. Try again—hold the buttons longer. It took me three attempts the first time.
The Honest Caveat
Resetting the counter buys you time, but the pad is still physically full. You'll get maybe 500–1000 more pages before it errors again. If you're in a humid environment or print borderless photos, the pad can leak and damage the printhead. So this reset is a temporary fix, not a permanent solution.
The right long-term fix is to replace the absorbing unit—it's a small plastic part with fresh sponges. You can order it online (search your model + "absorber"), or take it to a repair shop. If you're handy, watch a teardown video and do it yourself. It's about 30 minutes of work and a $15 part. Cheaper than a new printer.
Still Stuck? Check These
- Did the reset not stick? Reboot the printer, then re-enter Service Mode and check the counter value. If it's back to 100%, the EEPROM might be write-protected—older models do that. You'll need a different service tool version (try STV510 or STV500).
- Is the printer showing other errors? 5B00 sometimes pairs with 5B01 or 5B02, which mean the second counter (for the purge unit) is full. Same process, but reset all counters in the tool.
- Does the printer still not print? After the reset, run a cleaning cycle from the tool's "Test Print" tab. If the printhead is clogged from sitting too long, that'll help.
- Still stuck on 5B00 after multiple resets? The EEPROM may be failing, or the pad is truly saturated and leaking. Open the printer and inspect the pad area. If it's soaked and ink is dripping, stop resetting—replace the part.
Look, I've seen people burn through three resets and then wonder why ink is pooling under the printer. Don't be that person. Use this guide to get back printing today, but plan the pad replacement soon. Your printer will thank you.