ROOMBA·FAULT ERR 42 WARN

Roomba Error 42 — Lost on the Smart Map

Q: Roomba Error 42 — Lost on the Smart Map

Error 42 means the robot couldn't work out where it is on the Smart Map when you sent it to clean a specific room. It was probably moved by hand, or the room changed enough to be unrecognizable.

Severity: Warning — targeted cleaning fails until the robot can locate itself ijs

Last verified: 2026-07-05 Tools: none Time: ~10 min Difficulty: easy

DIRECT ANSWER

Error 42 means the robot couldn't work out where it is on the Smart Map when you sent it to clean a specific room. It was probably moved by hand, or the room changed enough to be unrecognizable.

#meaning · #causes · #fix · #models — link straight to any section

COMMON CAUSES · RANKED

Robot carried mid-job MOST COMMON

Picking it up and dropping it somewhere else severs its link to the map.

Room changed since mapping

Big furniture moves or renovations make the mapped landmarks useless.

Camera obscured or room dark

Dust on the lens or no light at all leaves the robot without visual anchors.

HOW TO FIX IT

No battery or electrical work involved in this fix.

Start from the dock

Put the robot on its dock and launch the job from there — that's its strongest reference point.

Don't relocate it mid-mission

If you must move it, expect it to re-localize slowly or fail.

Restore lighting and layout

Match the conditions the map was built under, and wipe the camera window clean.

Remap if the home changed for good

After a renovation or big furniture reshuffle, run a fresh mapping job.

Did this fix your robot?

No reports yet for this fix — be the first.

MODELS AFFECTED

Model	Status	Firmware	Parts	Verified
Roomba i1 / i1+	limited	i	Parts →	2026-07-05 · Source
Roomba i3 / i3+	limited	i	Parts →	2026-07-05 · Source
Roomba i4 / i4+	limited	i	Parts →	2026-07-05 · Source
Roomba i6 / i6+	limited	i	Parts →	2026-07-05 · Source
Roomba i7 / i7+	limited	i	Parts →	2026-07-05 · Source
Roomba i8 / i8+	limited	i	Parts →	2026-07-05 · Source
Roomba j7 / j7+	limited	j	Parts →	2026-07-05 · Source
Roomba j9 / j9+	active	j	Parts →	2026-07-05 · Source
Roomba s9 / s9+	limited	s	Parts →	2026-07-05 · Source
Roomba Combo j7+	limited	j	Parts →	2026-07-05 · Source
Roomba Combo j9+	active	j	Parts →	2026-07-05 · Source

Models resolved from the series chips above. Support status comes from our EOL library; rows link to the matching parts and firmware pages.

Sources

Verification

OFFICIAL SOURCE

Last verified: 2026-07-05 · How we verify a fault code

Corrections

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