Errors – Causes and Corrective Measures

Cause	Corrective measures
Measuring results inaccurate/implausible
Interfering objects are within the sensor range (8)	Remove all interfering objects (e.g. watches, bracelets, rings, etc.) from within range of the sensor (8). Do not hold the measuring tool close to the sensor.
Auto-calibration not successful	Manually recalibrate the measuring tool.
Light-up ring does not light up.
Measuring tool has switched off automatically.	Switch the measuring tool off and on again.
Batteries drained	Change the batteries.
Light-up ring lights up green/yellow/red in an uncoordinated manner.
Interference from electric, magnetic or electromagnetic fields	If possible, deactivate all tools whose radiation could interfere with the measurement and switch off the corresponding functions or tools.
Light-up ring flashes continuously, alternating green/yellow/red.
Measuring tool faulty	Send the measuring tool to an authorised Bosch after-sales service centre.

Error when searching for and indicating metal

Cause	Corrective measures
Light-up ring lights up yellow or red even though there is no metal nearby.
Ambient temperature too high/too low	Only use the measuring tool in the operating temperature range.
Strong temperature variation	Allow the measuring tool to reach the correct temperature.
Auto-calibration not successful	Manually recalibrate the measuring tool.
Light-up ring lights up yellow or red over a large measuring range on the wall.
Many metal objects spaced closely together	Metal objects spaced too closely together cannot be detected separately.
Building materials containing metal or reinforcing steel in concrete	In the presence of metallic building materials (e.g. foil-laminated insulation materials, heat conduction plates), reliable detection is not possible.
Solid metal objects on the back of the wall	In the presence of solid metal objects (e.g. radiators), reliable detection is not possible.
Auto-calibration not successful	Manually recalibrate the measuring tool.
Metal object not found.
Metal object is too deep or too small.	The detection depth depends on the building material and on the object and may be less than the maximum detection depth.

Cause	Corrective measures
Light-up ring lights up red over a large measuring range on the wall.
Insufficient earthing of the wall	Touch the wall with your free hand at a distance of 20−30 cm from the measuring tool in order to earth the wall.
Wall is too damp.	Only use the measuring tool when the humidity has been low for a few days and the wall is not damp.
Live cable not found.
No/unusual voltage in the cable	Apply voltage to the cable, e.g. by turning on the corresponding light switches. It is not possible to reliably detect multi-phase electricity cables and cables with voltages outside the 110−240 V and 50−60 Hz range.
Cable is too deep.	The detection depth depends on the building material and may be less than the maximum detection depth.
Cable runs in earthed metal pipe.	Be sure to look at the metal object display to find the metal pipe.
Measuring tool not earthed	Grip the measuring tool firmly without gloves. Do not stand on insulating ladders or scaffolds. Do not wear insulating footwear.
Shielding building material or humidity too low/too high	Detection will not be reliable in the presence of metallic building materials or building materials that are too dry or too damp (e.g. if the humidity is too low or too high).