Franklin Sensors ProSensor M90 Stud Finder Instruction Manual

Introduction

The Franklin Sensors ProSensor M90 is an advanced stud finder designed for accurately locating wood and metal studs behind various wall materials such as drywall. Featuring 9 precision sensors, it provides a clear indication of the full width and edges of studs, enhancing accuracy and ease of use for home improvement and construction projects. This manual provides essential information for the proper setup, operation, and maintenance of your ProSensor M90.

Package Contents

Franklin Sensors ProSensor M90 Stud Finder
Instruction Manual (this document)
Thank You Card

Contents of the Franklin Sensors ProSensor M90 package including the stud finder, box, and manual.

Image: The ProSensor M90 stud finder, its retail box, and accompanying documentation.

Setup

Battery Installation

The ProSensor M90 requires two AAA batteries (not included). It is important to use non-rechargeable batteries for optimal performance. Rechargeable batteries are not compatible with this device.

Locate the battery lid on the back of the unit. You will see lines indicating the release points.
To remove the lid, gently squeeze both ends of the battery lid together and lift it off.
Insert two AAA batteries into the battery compartment, ensuring correct polarity (+/-) as indicated inside the compartment.
Replace the battery lid by inserting one of the clips into the battery cavity first, then gently depress the other side of the battery cover to secure the second clip.

Step-by-step guide for installing AAA batteries into the Franklin Sensors ProSensor M90 stud finder.

Image: Visual instructions for opening the battery compartment, inserting batteries, and closing the lid.

Initial Test

After installing batteries, perform a quick test to ensure the device is functioning correctly. The M90 will only light up when it detects a change in density. You can test this by running your finger behind the unit while holding the button. The LEDs should illuminate.

Operating Instructions

General Operation

The ProSensor M90 is designed for simple, one-mode operation. No calibration is required before use.

Hold the Device: Grip the stud finder firmly with your fingers on the handle area, ensuring no fingers are over the sensor area.
Activate Scanning: Press and hold the button located on the top of the unit. The device will instantly begin scanning.
Scan the Wall: Place the stud finder flat against the wall and slowly slide it horizontally across the surface.
Identify Studs: As the device moves over a stud, the LED lights will illuminate, indicating the full width of the stud. The middle LED will turn green to indicate the stud's center.

The Franklin Sensors ProSensor M90 stud finder showing how it illuminates LEDs to indicate the full width of a stud.

Image: The stud finder in use, demonstrating its ability to show the full width of a stud with illuminated LEDs.

Key Features and Benefits

9-Sensor Accuracy: Equipped with 9 precision sensors, the M90 provides highly accurate detection of studs. This multi-sensor technology allows for a broader scanning area and more reliable results compared to conventional stud finders.
Full Width Detection: Unlike single-sensor devices that only indicate the edge or center, the ProSensor M90 illuminates multiple LEDs to show the entire width of the stud, including its edges and center simultaneously. This reduces guesswork and improves marking precision.
Deep Scan Capability: The device offers a 1 1/2-inch deep scan capability, allowing it to detect studs through various wall materials and textures, including sheetrock and drywall.
Wood and Metal Stud Detection: The M90 identifies changes in density, enabling it to detect both wood and metal studs without requiring different modes or settings.
No Calibration Required: The device automatically adjusts to different wall conditions, eliminating the need for manual calibration. Simply press and hold the button to begin scanning.

Diagram illustrating the 9 sensor fields of the Franklin Sensors ProSensor M90 and how it detects studs through drywall.

Image: An X-ray style view showing the 9 sensor fields of the ProSensor M90 detecting a stud behind drywall.

Close-up view of the Franklin Sensors ProSensor M90 highlighting its 9 LEDs, plastic shell, and battery compartment.

Image: Detailed view of the ProSensor M90, pointing out its 9 LEDs for visibility, durable plastic shell, and battery compartment.

Maintenance

Cleaning: Wipe the device with a soft, dry cloth. Do not use abrasive cleaners or solvents.
Storage: Store the ProSensor M90 in a cool, dry place away from direct sunlight and extreme temperatures. Remove batteries if the device will not be used for an extended period to prevent leakage.
Battery Replacement: Replace batteries when the device's performance diminishes or the LEDs do not illuminate as expected.

Troubleshooting

Problem	Possible Cause	Solution
Device does not turn on or LEDs do not light up.	Batteries are dead or incorrectly installed. Using rechargeable batteries (not compatible).	Check battery polarity and replace with fresh, non-rechargeable AAA batteries. Ensure non-rechargeable AAA batteries are used.
Inaccurate readings or inconsistent stud detection.	Fingers are over the sensor area. Wall surface is uneven or contains unusual materials. Presence of multiple or irregular stud configurations.	Ensure fingers are only on the designated handle area. Scan slowly and consistently. For complex walls, try scanning from different directions. The M90 is designed to show irregular configurations; interpret the LED pattern carefully. If all lights illuminate, it might indicate a very wide object or an unusual density change.
Device lights up randomly or all LEDs illuminate.	Presence of pipes, wiring, or other objects behind the wall. Scanning over a very dense area or a large, non-stud object.	The device detects changes in density. This could indicate non-stud objects. Exercise caution when drilling. Try scanning from the opposite side of the wall if possible, or use other methods to confirm.

Specifications

Model Number	M90 (FSM9002)
Dimensions	5.38 x 2.75 x 2 inches
Item Weight	7 ounces
Power Source	2 x AAA Batteries (not included, non-rechargeable recommended)
Detection Depth	Up to 1 1/2 inches
Stud Types Detected	Wood and Metal
Sensors	9 Precision Sensors
LED Indicators	Multiple LEDs for full stud width, Green LED for center
Manufacturer	Franklin Sensors
Date First Available	June 13, 2018

Warranty and Support

For information regarding product warranty, please refer to the documentation included with your purchase or visit the official Franklin Sensors website. If you encounter any issues or have questions about your ProSensor M90, please contact Franklin Sensors customer support for assistance.

You can find more information and support resources on the Franklin Sensors official store page: Franklin Sensors Store.

Franklin Sensors M90