Connection problems with your Cojali or other scan tool don’t have to get in the way of your equipment diagnostics and repairs. Many of today’s machines communicate through using the CAN protocol.  If you cannot communicate with your scan tool, this may be due to a problem on the vehicle side and not necessarily with your software. 

Here are a few things you can check quickly to determine where the problem lies, whether with the tool or with the machine:

Checking for Machine Connection Issues

If you’re using a machine that connects using a standard 9pin, the Can Communication is often on pins C and D. There are a few variations to the wiring, but you will want to start with the Can High and Can Low pins. From there, determine if your voltage is around 2.4V for Can Low and 2.6V for Can High. These will fluctuate slightly as messages are being sent, but they should equal 5V total.  If your voltage is low, you will need to look for a short to ground. If your voltage is high you should begin by checking for a short to power. If no voltage is present, check for an open circuit. 

The next thing to check will be resistance. You should make sure all modules are powered down, preferably by disconnecting the batteries. This should be around 60 ohms provided there are two terminating resistors. If all of this is normal it is time to check your hardware and software.

Troubleshooting Your Cojali Diagnostic Software Connection

Most diagnostic tools now have the ability to run a few simple checks to help you determine where the problem is located. Here are the steps to test your Cojali.

If it is not communicating with the laptop we recommend checking the cable going into the data link. If the cable is hooked up correctly then it is likely a machine issue – try going back to the steps above for checking the machine.

3. As you can see from running this test, we have communication on pins C and D and the results are good. At this point you should be able to communicate with the machine using your diagnostic tool.

Connect with Diesel Laptops

These tests will allow you to see where any communication issues lie. If you are still having difficulty connecting to your Cojali Jaltest Off-Highway Kit, contact our team for technical support.