When your scanner shows ‘No Communication’ and returns the error, it can stop the repair process. Now, if you depend on it for vehicle diagnostics, you will be in trouble. Modern cars with heavy and complex systems often rely on electronic modules; therefore, you need an active Bluetooth OBD2 scanner to communicate effectively.
When communication breaks down, it doesn’t mean the car has a major fault; it may just mean your tool is blocking the path. OBD2 scanners that support TPMS, ABS & SRS diagnostics can help ensure you’re covering all essential vehicle systems.
So, it is important to understand your diagnostic scan tool for Australian cars. In this guide, we’ll explore why these errors occur and how you can fix them for Australian vehicles, step by step.
Why Your Scanner Fails to Communicate
A vehicle diagnostic tool communicates with a vehicle's onboard systems through the OBD2 port. When that pathway is interrupted, it shows no communication error. This error can then cause many issues, from electrical to mechanical and even software-related.
Some of the major reasons for failing include:
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The OBD-II system has a blown fuse.
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Diagnostic connector pins that are broken or defective.
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Problems with the CAN (Controller Area Network) system of the car.
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Low battery voltage in the vehicle.
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Outdated or incompatible scan tool software.
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An issue with a particular control module.
Whether you are using a basic auto scanner or advanced automotive diagnostic tools, communication will work if all the above components function properly.
Step-by-Step Guide: How to Fix the Scanner's No Communication Error
Now, if you see an error in any of the best car diagnostic scan tools, how do you fix it? Here are some of the steps to follow:
1. Verify Power at the OBD-II Port
The OBD 2 connector is intended to provide power for the tool to operate. If the power is cut off, it shows no communication.
So, check the following for Scanner connection troubleshooting:
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Pin 16 ought to be 12V.
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Ground should be provided by pins 4 and 5.
If there is no power, check the car's fuse box for a damaged fuse related to the diagnostic port or accessory circuits.
2. Inspect the Scanner Cable and Connector
If a pin is loose, bent, or corroded in an OBD2 scanner for car owners, it can throw a wrench in communication right away. Here are some things to check:
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Cables from the scanner that might be damaged
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Pins that aren’t properly aligned or are pushed in
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Any signs of corrosion or moisture
Remember, even top-notch tools won’t work properly if the physical connection is off.
3. Check Vehicle Battery Health
When the system voltage is low, it can mess with all the electronic control modules. A weak battery might prevent these modules from starting up correctly, which could make your scanner display a ‘no communication’ error.
So, before you dive into any diagnostics, grab a multimeter and check that the battery is reading at least 12.4 volts.
4. Test Other Modules or Another Vehicle
One quick way to pinpoint the problem is to try connecting your scanner to another vehicle.
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If it works fine with the other vehicle, then the issue is likely with the original vehicle.
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But if it doesn't work on multiple vehicles, the scanner or cable might be the issue.
Doing this can save you time and help you steer clear of chasing after problems that aren't really there.
5. Identify CAN System Problems
Many cars today rely on a CAN network to enable different modules to communicate with each other. If that network has issues, the modules won’t work properly.
Here are some signs that may indicate a CAN problem:
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You might see several warning lights on your dashboard.
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Modules could start acting funny, turning on and off unexpectedly.
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Some parts, like power windows or your HVAC controls, might just stop working altogether.
When this happens, it often comes down to issues like shorts, open circuits, or damaged wiring in the network.
6. Use a More Advanced Scanner
Certain vehicles need more advanced diagnostics than what basic tools can provide. For example, a standard OBD-II tool might struggle with specific manufacturer systems or the latest protocols.
That's where a bi-directional scanner comes in handy. This type of scanner does more than just read data; it can also send commands to different modules, helping check whether the network is working and letting you dig into more detailed system info.
7. Confirm Scan Tool Software and Compatibility
Car manufacturers often refresh their communication protocols. So if your scan tool software isn’t up to date, it may have trouble recognising newer systems.
Here are a few things to check:
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Make sure your scanner's firmware is up to date.
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Verify that your scanner covers the right make, model, and year of the vehicle.
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Double-check that you’re choosing the correct protocol in the tool.
Incompatible software is a common yet often ignored reason for a scanner displaying ‘no communication’.
8. Inspect the Grounding System
Bad grounding can really mess up electronic communication. Many diagnostic problems are caused by a loose, corroded, or damaged ground strap.
So, be sure to check:
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The battery ground connection to the chassis
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The engine-to-chassis ground
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The grounds around the fuse boxes and control modules
Just clean and tighten those connections, and you should get that reliable communication back.
9. Check Specific Control Modules
If the Scanner is not communicating with the computer, this is another way to check.
If the scanner connects with some modules but not others, the problem could be with a specific ECU (Engine Control Unit), TCM (Transmission Control Module), or BCM (Body Control Module).
This situation indicates that:
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The module might be faulty
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There could be damaged wiring to that module
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The module may be offline because of an internal issue
At this point, we’ll need to run thorough diagnostics, check wiring diagrams, and conduct tests on module communication.
Conclusion
If your scanner shows ‘No Communication’, it doesn’t always indicate a major fault in the vehicle. Often, the issue lies with the connection, software, or power supply.
Using a reliable OBD2 scanner or advanced diagnostic tool can save time and prevent frustration. At Auto Lines Australia, we provide budget-friendly diagnostic tools and solutions to ensure smooth vehicle scanning, along with options to buy GPS trackers in Australia for complete vehicle monitoring.
Understanding your tools and following proper troubleshooting steps ensures accurate diagnostics for your car. This gives you confidence on the road while keeping repairs efficient and cost-effective.
FAQs
1. What should I do if my scanner is not communicating with my computer?
Check connections, USB or Bluetooth pairing, power supply, and software compatibility. Update your scan tool firmware and ensure the correct protocols are selected for smooth communication.
2. How can I quickly fix a scanner with no communication error?
Verify OBD-II port power, inspect cables, check vehicle battery, test other modules, and update scanner software. Using a quality OBD2 scanner often resolves communication issues.
3. What are common scanner connection troubleshooting steps for USB or network issues?
Check USB ports, network adapters, and cable integrity. Restart the software, ensure the firmware is up to date, and confirm the correct vehicle protocols to restore scanner communication.
