Network Cable Connected but No Internet – How to Troubleshoot with FNIRSI LPM-10A Malaysia
Network Cable Connected but No Internet – How to Troubleshoot with FNIRSI LPM-10A Malaysia
The Ethernet cable is connected.
The network port light may even be blinking.
But the computer still shows:
No Internet
or
No Network Access
Does this automatically mean the internet service is down?
No.
The problem could be caused by the network cable, RJ45 termination, switch port, network equipment or network configuration.
For technicians in Malaysia, a multifunction network tester such as the FNIRSI LPM-10A can help check the physical network connection before moving deeper into software and configuration troubleshooting.
First Question: Is It a Cable Problem or Network Problem?
This is the first thing to determine.
A network connection involves several components:
Device → RJ45 Cable → Wall Outlet → Installed Cable → Patch Panel → Network Switch → Router / Network
A fault anywhere along this path may result in no network access.
Do not immediately replace the router or network switch.
Start with the physical connection.
Step 1: Check the RJ45 Cable
Inspect the Ethernet cable first.
Look for:
Loose RJ45 connector
Broken connector clip
Damaged cable
Crushed cable
Sharp bends
Poor termination
Corrosion or moisture
Loose wall outlet
If possible, temporarily replace the patch cable with a known-good cable.
If the connection immediately returns to normal, you have already narrowed down the problem.
Step 2: Test the Cable Wiring
If the cable looks normal externally, check its wiring.
A cable can look perfectly good while having an internal termination problem.
The FNIRSI LPM-10A provides network cable testing functions that can help technicians inspect the cable connection.
This is particularly useful after:
Installing a new RJ45 connector
Replacing a wall outlet
Re-terminating a network cable
Repairing an existing network point
Moving office equipment
Do not assume that a newly terminated connector is correct simply because all eight wires are visible inside the plug.
Test it.
Step 3: Check the Cable Length
For permanently installed cabling, the problem may not be visible from either end.
The cable could travel:
Above the ceiling
Inside a wall
Through a cable tray
Between floors
Across a warehouse
Through a factory
The FNIRSI LPM-10A cable length measurement function provides additional information about the cable run.
If the measured condition or length appears inconsistent with what is expected, further investigation of the cable route may be required.
Step 4: Find the Correct Cable in the Network Cabinet
Suppose the problem is at:
Office Network Point B-17
You go to the server room and find dozens of Ethernet cables.
Which one is B-17?
If the labels are missing or unreliable, guessing can waste time.
The cable tracing function of the LPM-10A can help identify the corresponding cable.
This is particularly useful in older commercial installations where the original network documentation has not been maintained.
Step 5: Identify the Switch Port
After finding the cable, determine which network switch port it is using.
The port flashing function can assist technicians in identifying the corresponding switch port.
Once the correct port has been identified, inspect it.
Ask:
Is the link indicator active?
Is another known-good device working on this port?
Does moving the connection to another suitable port change the result?
Is the switch itself operating normally?
This separates a cable problem from a possible switch-port problem.
Step 6: Check PoE When Applicable
If the connected device requires Power over Ethernet, the troubleshooting process should also include PoE.
Examples include:
IP cameras
Wireless access points
VoIP phones
Access-control equipment
The FNIRSI LPM-10A includes PoE detection capability, helping technicians determine whether PoE is present at the connection.
This is important because:
Network connection problem
and
PoE power problem
are not necessarily the same fault.
Why Can a Network Cable Look Normal but Still Have Problems?
Ethernet troubleshooting is more complicated than simply asking whether there is electrical continuity.
A cable may have:
Poor termination
Intermittent connection
Damaged conductors
Connector problems
Installation damage
Excessive or problematic cable run
Network equipment issues
Therefore, seeing an LED or obtaining a basic continuity result should not automatically end the investigation.
What If the Cable Tests Normally?
This is an important point.
A network cable tester does not diagnose every possible reason for “No Internet.”
If the physical cable and connection appear normal, move to the network side.
Possible causes can include:
DHCP problems
Incorrect IP settings
DNS problems
Router problems
Switch configuration
VLAN configuration
Network authentication
Internet service interruption
Firewall or security settings
Computer network adapter problems
The FNIRSI LPM-10A should therefore be used as part of the troubleshooting process rather than as proof that every part of the network is functioning correctly.
A Better Troubleshooting Sequence
When a customer says:
“LAN cable connected but cannot access internet.”
Avoid changing everything at once.
Use a logical sequence:
1. Inspect the physical connection
↓
2. Try a known-good patch cable
↓
3. Test the network cable
↓
4. Trace the installed cable
↓
5. Identify the switch port
↓
6. Check PoE if required
↓
7. Check the network connection
↓
8. Investigate IP, DHCP, DNS, VLAN or router configuration
This approach helps isolate the problem.
Example: One Office PC Has No Internet
Imagine an office has 20 computers.
Nineteen computers are working normally.
Only one computer cannot connect.
In this situation, a complete internet service failure is less likely.
Start with the affected workstation.
Check:
Patch cable
Wall outlet
Installed network cable
Switch port
Computer network adapter
If the LPM-10A helps confirm the physical cabling path, you can then concentrate on the remaining network or computer-related possibilities.
Example: Entire Office Has No Internet
Now consider a different situation.
All 20 computers lose internet access at approximately the same time.
It would make little sense to test all 20 Ethernet cables first.
Instead, investigate shared infrastructure such as:
Router
Main network switch
Internet connection
Power supply
Upstream network equipment
The pattern of the fault tells you where to start.
One Device vs Many Devices
This is a simple but powerful troubleshooting principle.
One device affected:
Start locally.
Many devices affected:
Look for shared infrastructure.
A network cable tester is especially useful when the problem appears to be limited to an individual cable, outlet or network device.
FNIRSI LPM-10A for Office Network Troubleshooting
The advantage of the FNIRSI LPM-10A is that technicians can perform several physical network troubleshooting tasks using one handheld instrument.
Depending on the situation, you may need to:
Check the cable
Trace the cable
Measure cable length
Identify the switch port
Check PoE
Perform network-related testing
This makes it more useful for professional field work than a simple RJ45 wire-map tester when dealing with existing installations.
Suitable Applications in Malaysia
The FNIRSI LPM-10A can be considered for:
Office network maintenance
CCTV installation
IT support
Server-room maintenance
Structured cabling
Retail outlets
Factories
Warehouses
Schools
Commercial buildings
Building maintenance
It is particularly useful when technicians frequently inherit network installations installed by somebody else.
FNIRSI LPM-10A Network Cable Tester Malaysia
If your network cable appears connected but the network is still not working, do not immediately assume that the cable—or the internet service—is the only possible cause.
Test systematically and isolate the fault section by section.
For FNIRSI LPM-10A Network Cable Tester enquiries, availability or help selecting a suitable network testing instrument, contact MTM Precision Sdn Bhd.
MTM Precision Sdn Bhd
Showroom & Service Centre:
No. 29-1 & 29-2, Jalan Bandar 18,
Pusat Bandar Puchong,
47160 Puchong, Selangor, Malaysia.
Tel: 03-8080 7172
WhatsApp: +6016-660 7346
Email: mtmpre@yahoo.com
Website: www.mtmpre.com.my
You may WhatsApp us a photo of the network cable, RJ45 outlet, network cabinet, switch or installation and explain the problem you are trying to troubleshoot.
Supply and enquiries throughout Malaysia, including Selangor, Kuala Lumpur, Johor, Penang, Melaka, Negeri Sembilan, Perak, Pahang, Kelantan, Terengganu, Kedah, Perlis, Sabah and Sarawak.
06 Oct 2026
