After the check engine light appeared on my car, I tried to connect the OBD 2 diagnostic scan tool to show an error instead of showing the trouble codes. This issue prompted me to research online and ask different technicians what the issue might be. Unfortunately, a good number of motorists encounter this problem and usually don’t know why it occurs.
Why is OBD2 Not Linking?
But after conducting research online and speaking to different mechanics and technicians, I found out that a wide range of problems can cause it. These issues include an incompatible obd2 scan tool, bad fuses, OBD2 port not working, damage in the circuit board, ECU, and failed computer. So let’s check the reasons.
OBD2 Tool Compatibility
First and foremost, you should identify what types of OBD your car is. In most cases, these issues can be rectified and amended to allow you to read the error codes. You should inspect whether the code reader is compatible with your vehicle or not, as there are huge differences between OBD1 and OBD2. Test it with another car and see if it functions. If it doesn’t, then probably, the issue is not with the scan tool.
A Bad Fuse
Afterward, try checking the fuses and see if they are working fine. If there is a bad fuse, you will continue receiving the error when linking the obd2 to the computer. Get the blown Fuse replaced so that you can detect the error codes and allow them to be displayed.
Low Voltage Supply
Most of the OBD2 port comes with 16 pins, and they must need 12-v power to connect with the vehicle. So check the DC voltage using a voltmeter if the current power is below 11 volts. If it shows a lower voltage, you should inspect the charging system or battery first. But if you don’t get any readings on the meter, a blown fuse is the possible reason. So just change the fuse to reconnect the device.
Related article: What are the symptoms of Ignition Coil Problems?
Check the ECU and Ports
In addition, one of the computers might be the problem. But identifying this is very difficult as a result of the data transferred between the two controllers. So, you will need to check the main ECU. Another way of identifying what the cause or the no linking could be is by testing pin to pin check with a wiring schematic while utilizing a voltmeter to inspect every single wire.
Turn on the Ignition Key
Most of the OBD2 scanners only work when you turn on or start the car engine. So if your OBD2 is not linking, make sure you have switched the Ignition Key in the run position. Then, give some time to boot up the system. Otherwise, it may not connect to the OBD2 connector. Once your boot-up and dashboard activity has been finished, your scanner will engage with your vehicles.
Operating an OBD2 tool is quite a straightforward task, but sometimes you may face some difficulties connecting the device with the vehicles. On some rare occasions, it shows- “No-Communication!” which means there is a communication error between your OBD2 scanner and car. If your OBD2 not linking and you are not able to find out what the issue is, you can visit a mechanic to figure out and correct any errors.