Experiencing a check engine light in your 2000 Jeep Cherokee can be concerning, and your first step is usually to plug in a scan tool to diagnose the issue. However, what if you find that your OBD2 connector isn’t powering up the scan tool? This can be a frustrating roadblock. Let’s explore the common reasons why your 2000 Jeep Cherokee’s OBD2 connector might not be working and how you can troubleshoot the problem.
One of the most frequent culprits for a non-functional OBD2 port is a simple blown fuse. In the case of your 2000 Jeep Cherokee, the OBD2 connector, also known as the Data Link Connector (DLC), receives power from fuse F17 located in the Power Distribution Center (PDC). If this fuse is blown, it will cut off power to the connector, preventing your scan tool from powering on. It’s worth noting that fuse F17 also powers other circuits, such as the headlamps. If your headlights are also not working, a blown F17 fuse becomes even more likely.
Another potential issue lies within the ground connections for the OBD2 connector. The 2000 Jeep Cherokee OBD2 connector utilizes ground pins located on the top row, specifically the second and third cavities from the left. These ground wires are typically connected to the oil dipstick tube mounting bracket stud on the engine’s left side. A loose, corroded, or broken ground connection can prevent the OBD2 port from functioning correctly.
To diagnose the problem, you’ll need a voltmeter. Begin by checking for power at the OBD2 connector itself. Locate the power pin, which is on the far right of the bottom row of pin cavities. Using your voltmeter, measure the voltage between this power pin and one of the ground pins on the top row. You should see a reading of approximately 12V DC. If you don’t get a reading, try the other ground pin cavity. If voltage is still absent, inspect the ground wires at the oil dipstick ground point for any signs of damage or corrosion. If the wires appear intact, use an ohmmeter to test continuity between each ground pin cavity and a known chassis ground. You should find continuity, ideally 0.5 ohms or less.
Finally, physically examine the OBD2 connector itself. Check for any corrosion within the pin cavities. Also, ensure that the pins haven’t been damaged or expanded due to improper use of scan tool connectors or probing. If the pin cavities are damaged, it may prevent proper contact and power delivery to your scan tool.
By systematically checking the fuse, ground connections, power supply, and the connector itself, you should be able to pinpoint why your 2000 Jeep Cherokee OBD2 connector is not working, and get your diagnostic process back on track. If after checking these points the issue persists, there could be more complex problems with the vehicle’s communication circuits, which might require further professional diagnosis.
