
Situation Probable Cause Solution
Detects other objects
besides studs in
StudScan mode.
Finds more targets
than there should be.
• Electrical wiring and metal/
plastic pipes may be near
or touching back surface
of wall.
• Scan the area in Metal Scan and AC Scan to determine if metal or hot AC is present.
• Check for other studs equally spaced to either side 12, 16, or 24 in. (31, 41, or 61 cm)
apart or for the same stud at several places directly above or below the first scan area.
• A stud reading would measure approximately 11⁄2 in. (38 mm) apart from each edge;
anything larger or smaller is most likely not a stud if not near a door or window.
Area of voltage
appears much larger
than actual wire
(AC only).
• Voltage detection can
spread on drywall as much
as 12 in. (31 cm) laterally
from each side of an actual
electrical wire.
• To narrow detection, turn unit off and on again at the edge of where wire was first
detected and scan again.
• The scanner may have been calibrated over a metal object, reducing sensitivity. Try
calibrating in another location.
• Scan in both horizontal and vertical directions. Metal sensitivity is increased when
metal object is parallel to sensor, located under item.
• Tool calibrated over metal
object.
• Metal targets too deep or
small.
Difficulty detecting
metal.
Image of metal object
appears wider than
actual size.
• Metal has greater density
than wood. • To reduce sensitivity, recalibrate SMA19 over either of first two marks.
Constant readings of
studs near windows
and doors.
• Double and triple studs are
usually found around doors
and windows. Solid headers
are above them.
• Detect outer edges so you know where to begin.
• Wires are shielded by metal
conduit, a braided wire layer,
metallic wall covering,
plywood shear wall, or other
dense material.
• Wires deeper than 2 in.
(51mm) from surface might
not be detected.
• Wires may not be live.
• Try Metal Scan mode to see if you can find metal, wire, or metal conduit.
• Use extra caution if the area has plywood, thick wood backing behind drywall,
or thicker than normal walls.
• If a switch controls an outlet, make sure it is ON for detection, but turned off when
working near electrical wires.
Use CAUTION when nailing, sawing, or drilling into walls, floors, and ceilings
where these items may exist.
You suspect electrical
wires, but do not
detect any.
Low Battery Indicator
and tool not operating.
• Battery level low for proper
operation. • Replace with brand new 9 V battery.
9. HEL PFUL HINTS (See also number 2, Operating Tips)