When an airless sprayer stops during a job, the cause is usually power-related, supply instability, or a protective shutdown (error code). Below is a practical, step-by-step checklist to diagnose the issue quickly.

⚠️ Safety first: switch the unit OFF, unplug it, and relieve pressure according to the manufacturer’s procedure before inspecting anything.

1) Check that the sprayer is getting proper mains power

Many random shutdowns come from unstable or insufficient power.

  • Try a different wall outlet (ideally on a different circuit).
  • Avoid overloaded jobsite power strips.
  • If available, use a multimeter to confirm the voltage is normal for your region (often ~230V in EU).

👉 Low voltage under load can trigger shutdowns and error codes.

Airless machine no longer works - AI

2) Check the building/floor breaker or fuse

A breaker may:

  • have tripped,
  • be half-tripped,
  • or trip only under load (when the sprayer is working hard).

Actions:

  • Check the electrical panel and reset the relevant breaker.
  • If it keeps tripping, suspect overload, a bad outlet, or a damaged cable.

Check the building's fuse/circuit breaker - AI

3) Inspect the sprayer power cord for damage

A damaged cord can cause:

  • intermittent cut-outs,
  • protective shutdown,
  • overheating and safety risks.

Look for:

  • cuts, crushed sections, exposed insulation,
  • loose plug,
  • damage near the strain relief.

➡️ If in doubt: replace the cord or have it serviced—don’t “tape-fix” it.

4) If you use an extension cord: keep it under 20 m (otherwise plug directly into the wall)

Long or undersized extension cords create voltage drop, reducing motor power and potentially causing shutdown.

Best practice:

  • Keep it ≤ 20 m and use a heavy-duty cable.
  • If you have to go far: choose a shorter extension cord with a larger cross-section, or move the power source closer.
  • As a quick test: plug the sprayer directly into a wall outlet. If the problem disappears, the extension is the culprit.

Do not exceed 20 m of extension cord with an airless sprayer - AI

5) Make sure the unit is not connected to a generator

Many generators provide unstable voltage/frequency, which can confuse the electronics and cause stoppages.

If you were using a generator:

  1. Unplug the sprayer from the generator
  2. Turn it OFF
  3. Plug into a mains wall outlet
  4. Restart and test

On some sprayers (including Graco/Wagner), low input voltage can prevent operation.

Electric generator with an airless pump - AI

6) Check the indicator lights (ON/OFF / blinking)

Lights are a fast clue:

  • Lights ON but pump stops: likely an error code, control issue, or a mechanical load problem.
  • No lights / dead display: points to power supply, cord, switch, control board, or motor.

Note exactly what is lit or blinking and when the shutdown occurs.

7) Check for an error code (example: Graco E05 and E08)

Error codes narrow the diagnosis immediately.

Graco E08 (common causes: extension cords / generator / low supply voltage)

In Graco diagnostic tables, CODE 08 indicates the input voltage is too low for the sprayer to operate, with recommended actions like switching OFF, removing other equipment from the circuit, and finding a proper supply voltage.

Practical fixes:

  • plug directly into mains,
  • remove long/undersized extensions,
  • avoid generators,
  • try another circuit/outlet.

Error code 08 at Graco

Graco E05 (common causes: motor/control/pump load)

In some Graco troubleshooting guidance, “Display shows E=05” appears in a “sprayer does not run” scenario, with possible causes including a locked/frozen pump or drive train, an open connection between motor and control, motor/control board issues, or excessive motor amp draw.

Typical manufacturer-style approach:

  • disconnect/remove the pump and test: if the motor runs without the pump, the pump/drive is binding.
  • check motor/control connectors (clean and secure),
  • then proceed to motor checks (brushes on some models) and replace motor or control board if diagnosis confirms it.

Important: depending on the Graco series, the exact meaning may vary. The model’s diagnostic table (manual) remains the reference.

8) Inspect the pump lower (inlet valve / piston / blockage)

If power supply is good but the unit shuts off under load, look for mechanical restriction:

  • Check the pump lower for debris, dried paint, or contamination blocking:

    • the inlet valve,
    • the outlet/check valve,
    • or piston movement.

Symptoms:

  • the motor strains then stops,
  • poor priming,
  • pressure fluctuations before shutdown.

➡️ Cleaning/maintaining the bottom of the pump often solves the problem… especially after a shutdown without thorough cleaning.

9) If nothing powers on: motor/control board checks + warranty/repaired service

If nothing lights up and you already eliminated:

  • outlet,
  • breaker,
  • cord,
  • extension/generator issues,

then the issue may involve:

  • the ON/OFF switch, internal power supply, control board, or motor.

In this case:

  • if you are unsure of the diagnosis (or if the device no longer turns on at all), it is recommended that you contact the retailer to activate the 2-year manufacturer’s warranty if the device is covered,
  • otherwise: send the machine for repair to an authorised professional (to avoid aggravating the fault and to ensure safety).

An airless sprayer that switches off during use is very often related to:

  1. the power supply (socket, circuit breaker, cable, extension cord, generator),
  2. an error code (e.g. E08 voltage too low),
  3. abnormal mechanical stress (blocked pump/piston/valves),
  4. or, more rarely, a motor/board fault (e.g. diagnosis E05).

At Airless Discounter, we recommend always starting with the “simple” checks (mains/extension cord) before opening or dismantling anything.

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For any further questions or if you would like to get your hands on one of these products seen in this article, you can contact us on +49 (0) 30 220 15436, fill out our contact form or email us. If you wish to purchase one of the products mentioned above, you can check them out in our online store. You can also visit us at our service base during office hours.