Excavator fault codes are diagnostic messages generated by your machine's onboard computer system. Think of them as your excavator's way of telling you something's wrong. These alphanumeric codes pop up on your monitor when sensors detect problems with the engine, hydraulics, electrical systems, or other components.

Each manufacturer uses its own coding system. A "CA553" on a Caterpillar means something different than a code on a Komatsu or Hitachi. That's why having access to brand-specific fault code lists matters. Modern excavators can generate hundreds of different codes, ranging from minor sensor glitches to serious engine failures that need immediate attention. Ignoring these warnings often leads to bigger problems down the road—and bigger repair bills.

Different excavator brands use different diagnostic systems, but some issues show up across all machines. Here's a quick look at what you might see:

We stock machines from all these brands at Fair Trade Machinery, and our team knows the common trouble spots for each one. If you're dealing with repeated fault codes on an older machine, it might be time to consider an upgrade. Just reach out—we'll help you figure out if repair or replacement makes more sense for your situation.

Reading fault codes isn't hard once you know where to look. Most modern excavators display codes directly on the monitor panel. Here's the basic process:

First, turn the key to the "on" position without starting the engine. Many machines will run a self-diagnostic check and display any active codes. Write down the exact code—letters, numbers, all of it. Some machines show multiple codes at once, so scroll through the entire list.

Next, check your operator's manual or service documentation. The manual usually has a fault code chart in the back. If you don't have the manual, you can often find code definitions online or by contacting your dealer. Some codes are informational only, while others indicate serious problems. Codes related to engine temperature, hydraulic pressure, or fuel systems usually need quick attention. Electrical and sensor codes sometimes clear on their own after a restart.

Pro Tip from our mechanics: About 30% of fault codes we see on used excavators are sensor-related, not actual component failures. A dirty sensor or loose connector can trigger warnings that look scary but are cheap fixes.

Got a fault code and not sure what to do? Here are some practical steps:

Start with the simple stuff. Check your fuel level, coolant, and hydraulic fluid. Low levels trigger fault codes more often than you'd think. Look for loose wires, corroded connectors, or damaged hoses. A visual inspection catches a lot of problems.

If the code persists after basic checks, you'll need diagnostic software or a qualified technician. Many codes require clearing through the machine's computer system—they won't just go away on their own. Keep a log of recurring codes, too. If you see the same code pop up repeatedly, that pattern tells you something about what's actually failing.

And if you're buying a used excavator, always ask for a fault code history. Machines with clean records are worth more and cause fewer headaches. We provide full diagnostic reports on every excavator we sell.

Dealing with fault codes you can't figure out? Looking for a used excavator with a clean service history? Our team at Fair Trade Machinery is here to help. We've got years of experience with Caterpillar, Komatsu, Hitachi, Sany, XCMG, and other major brands.

Send us a message or request a quote today. We'll answer your questions and help you find the right machine for your needs.

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How do I clear fault codes on my excavator?

Most fault codes require a diagnostic tool or dealer software to clear. Some codes will reset after you fix the problem and restart the machine, but persistent codes usually need professional clearing. Check your operator's manual for model-specific instructions.

What does a flashing fault code mean?

A flashing code typically indicates an active, ongoing problem. Solid or steady codes often mean the issue happened in the past but isn't currently active. Flashing codes usually need immediate attention to prevent damage.

Can I still operate my excavator with a fault code showing?

It depends on the code. Some are warnings that let you keep working with caution. Others—especially engine, hydraulic, or safety-related codes—mean you should stop operation immediately. When in doubt, shut it down and get it checked.

Where can I find fault codes for my specific excavator model?

Your operator's manual is the best source. You can also contact your dealer or check manufacturer websites. We list common codes by brand right here on our site.

Do used excavators come with fault code history?

They should. Reputable sellers provide diagnostic reports showing past and current codes. At Fair Trade Machinery, we include full fault code histories with every machine we sell.