Cordless vacuum shows F2 and refuses to run when the filter is removed or after filter cleaning.

Safety first: Remove the battery pack before working near the filter compartment.

Refit the filter correctly:

• Remove the pre‑motor filter and inspect it for damage or warping. Replace if misshapen.
• Reinsert the filter fully into its housing, aligning any arrows or tabs as shown in the Salter manual.
• Close the filter cover firmly until it clicks.

Inspect the cover and switch:

• Check the filter cover latch for cracks or wear that prevent it from pressing the internal microswitch.
• Clean any dust build‑up around the switch area using a soft brush.

If F2 remains, the filter door microswitch or sensor is likely defective and will need replacement, usually as part of the main body housing or wiring harness.