1. Product Overview
The Yuecoom MESTEK WT-58D is a multifunctional wire tracker designed for testing telephone lines, network cables, and power cables. It is an essential tool for integrated wiring network engineering, building monitoring line maintenance, and general network maintenance tasks. The device consists of two main units: an Emitter (Transmitter) and a Receiver.
Key Features:
- Integrated wiring network engineering and building monitoring line maintenance.
- Equipped with RJ11 and RJ45 interfaces on the transmitter for versatile connectivity.
- Enables easy and fast location of breakpoints without stripping wire insulation.
- Supports short-circuit and open-circuit detection.
- Includes DC level testing function.

Image 1.1: The MESTEK WT-58D Network Cable Tester, showing both the Emitter and Receiver units.
2. Package Contents
Before beginning, please verify that all items listed below are present in your package:
- 1 x Receiver Unit
- 1 x Transmitter Unit
- 1 x RJ11 Connecting Cable
- 1 x RJ45 Connecting Cable
- 1 x User Manual (this document)
- 1 x Line Finder Bag
- 1 x Pair of Earphones

Image 2.1: All components included with the MESTEK WT-58D Network Cable Tester: Receiver, Transmitter, RJ11 cable, RJ45 cable, earphones, and carrying bag.
3. Setup
3.1 Battery Installation
Both the Transmitter and Receiver units require two 9V 6F22 batteries each (not included in the package). To install the batteries:
- Locate the battery compartment cover on the back of each unit.
- Slide or unclip the cover to open the compartment.
- Insert the 9V battery, ensuring correct polarity (+/-).
- Close the battery compartment cover securely.
3.2 Connecting Cables
The Transmitter unit features both RJ11 and RJ45 ports. The Receiver unit has an RJ45 port and a probe for non-contact detection.
- For RJ11 (Telephone) Cables: Connect one end of the RJ11 cable to the RJ11 port on the Transmitter and the other end to the telephone line or device to be tested.
- For RJ45 (Network) Cables: Connect one end of the RJ45 cable to the RJ45 port on the Transmitter and the other end to the network cable or device to be tested.

Image 3.1: Close-up view of the Emitter unit, highlighting the RJ11 and RJ45 connection ports.
4. Operating Instructions
The MESTEK WT-58D offers various testing modes for different applications.
4.1 Powering On/Off
Press the power button (green button with power symbol) on both the Transmitter and Receiver units to turn them on. Press again to turn off.
4.2 Cable Continuity Test (RJ11/RJ45)
This mode is used to check for open circuits, short circuits, and correct wiring sequence in network and telephone cables.
- Connect the cable to be tested to the appropriate port (RJ11 or RJ45) on the Transmitter unit.
- Connect the other end of the cable to the RJ45 port on the Receiver unit.
- Turn on both units.
- Observe the LED indicators on both units. The LEDs (1-8, G) will light up in sequence, indicating the status of each wire.
- Normal Connection: LEDs on both units light up in the same sequence (1-2-3-4-5-6-7-8-G).
- Open Circuit: If a specific LED does not light up on either unit, that wire is open.
- Short Circuit: If two or more LEDs light up simultaneously or in an incorrect sequence, a short circuit is present.
- Crossed Wires: LEDs will light up in a different sequence on the Receiver compared to the Transmitter.
4.3 Line Finding Function
This function helps locate a specific cable among a bundle of cables.
- Connect the cable to be traced to the appropriate port on the Transmitter unit.
- Turn on the Transmitter unit.
- Turn on the Receiver unit.
- Use the probe of the Receiver unit to scan the bundle of cables. The Receiver will emit an audible tone when it detects the signal from the traced cable.
- Adjust the sensitivity of the Receiver if necessary using the 'Q' button or sensitivity control (if available) to pinpoint the exact cable.
4.4 Short-Circuit/Open-Circuit Detection & DC Level Testing
These functions are integrated into the continuity test and line finding modes. The LED indicators provide visual feedback for short/open circuits. The device can also detect DC voltage levels on lines, indicated by specific LED patterns or tones.

Image 4.1: The MESTEK WT-58D Network Cable Tester being used to identify cables in a complex wiring environment.
5. Maintenance
5.1 Battery Replacement
When the LED indicators dim or the device functions erratically, it is time to replace the batteries. Refer to Section 3.1 for battery installation instructions.
5.2 Cleaning
Wipe the device with a soft, dry cloth. Do not use abrasive cleaners or solvents, as these can damage the casing and electronic components.
5.3 Storage
Store the MESTEK WT-58D in a dry place, away from direct sunlight and extreme temperatures. The recommended storage environment is -10℃ to 50℃ with 10%-90% relative humidity. Remove batteries if the device will not be used for an extended period to prevent leakage.
6. Troubleshooting
- Device does not power on:
Check if batteries are installed correctly with the right polarity. Ensure batteries have sufficient charge. Replace with new batteries if necessary. - No signal detected during line finding:
Ensure both Transmitter and Receiver are powered on. Verify the cable is securely connected to the Transmitter. Increase the Receiver's sensitivity. Check for severe cable damage. - Inconsistent LED readings during continuity test:
Ensure cable connectors (RJ11/RJ45) are fully inserted and not damaged. Check for bent pins in the ports. Test with a known good cable to rule out device malfunction. - Weak or distorted audio from Receiver:
Check battery level. Ensure earphones are properly plugged in (if used).
7. Specifications

Image 7.1: Physical dimensions of the MESTEK WT-58D Emitter and Receiver units.
| Feature | Specification |
|---|---|
| Model | WT-58D |
| Working Environment | 0℃ - 40℃, 20%-75%RH |
| Storage Environment | -10℃ - 50℃, 10%-90%RH |
| Altitude | ≤2000 meters |
| Distance of Sending Signal | 0-300m |
| Battery Type | 2 x 9V 6F22 (Not Included) |
| Receiver Dimensions (L x W x H) | 190mm x 40mm x 23mm (Approx.) |
| Transmitter Dimensions (L x W x H) | 140mm x 60mm x 25mm (Approx.) |
| Item Weight | 350 g (Total, approx.) |
| Connectivity | RJ11, RJ45 |
8. Warranty and Support
This product comes with a 24-month product warranty from the date of purchase. If you encounter any issues or have questions regarding the MESTEK WT-58D Network Cable Tester, please contact the seller or manufacturer's customer support. They will assist you with troubleshooting, warranty claims, or any other product-related inquiries.