Kärcher HDS 10/21-4 ST error codes & fixes
Choose an error code below to jump to the exact fix. If you’re not sure, use the model-scoped search.
Try E2, temperature, or won’t start.
Error codes
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Recently updated fixes
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Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 8X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 8X means communication fault. This guide explains the likely causes, the safest first checks, and when support or service i…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 7X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 7X means water outlet temperature sensor fault. This guide explains the likely causes, the safest first checks, and when su…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 6X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 6X means flame sensor LED too bright or too dark. This guide explains the likely causes, the safest first checks, and when…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 5X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 5X means water shortage or dry running. This guide explains the likely causes, the safest first checks, and when support or…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 4X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 4X means exhaust gas fault. This guide explains the likely causes, the safest first checks, and when support or service is…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 3X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 3X means winding protection contact fault. This guide explains the likely causes, the safest first checks, and when support…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 2X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 2X means current/voltage fault (asymmetry, over/under current, or over/undervoltage). This guide explains the likely causes…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 1X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 1X means leakage on the device. This guide explains the likely causes, the safest first checks, and when support or service…
All fixes for this model
One card per code. If a code has multiple variants, the card opens the filtered results list.
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 8X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 8X means communication fault. This guide explains the likely causes, the safest first checks, and when support or service i…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 7X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 7X means water outlet temperature sensor fault. This guide explains the likely causes, the safest first checks, and when su…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 6X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 6X means flame sensor LED too bright or too dark. This guide explains the likely causes, the safest first checks, and when…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 5X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 5X means water shortage or dry running. This guide explains the likely causes, the safest first checks, and when support or…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 4X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 4X means exhaust gas fault. This guide explains the likely causes, the safest first checks, and when support or service is…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 3X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 3X means winding protection contact fault. This guide explains the likely causes, the safest first checks, and when support…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 2X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 2X means current/voltage fault (asymmetry, over/under current, or over/undervoltage). This guide explains the likely causes…
Kärcher HDS 10/21-4 ST Error Code SERVICE INDICATOR LIGHT FLASHES 1X
Kärcher HDS 10/21-4 ST error code SERVICE INDICATOR LIGHT FLASHES 1X means leakage on the device. This guide explains the likely causes, the safest first checks, and when support or service…
About this model
If your device shows an error code, start with the matching fix page. When a code returns repeatedly, it often points to an underlying cause (temperature, power delivery, sensors, locks, or wear).
Always follow basic safety: unplug before opening anything, and stop if you smell burning or see damage.