In the case of a blown fuse issue. You will need to replace the blown fuse. The fuse kits that we usually buy are: and

The first link is for mini fuses that I have seen on vans and smaller passenger cars. The second link is for larger fuses that I have seen on trucks.

Here are the basic instructions for how to locate and replace a blown fuse:

1. Check to make sure the OBD port is not powered. This can be done by plugging in the OBD device into the port. If the device does not light up, then it may be a fuse issue.

2. Locate the fuse box. It is usually located near the OBD port, but can be located elsewhere depending on truck model.

3. Use the yellow colored "fuse checker" tool to check if the fuse has been blown. Start by adjusting the size of the probes to match the size of the fuse's two openings. Then put the tool to the openings and the green light on the tool should light up. If it does not, then the fuse needs to be replaced.

4. To replace the fuse, first make note of the location of the fuse. It is very important that you place the new fuse in the location of the old fuse.

5. Remove the blown fuse using the other side of the fuse check or pliers.

6. Double check that the fuse has been blown. You can tell if it is blown if the metal strip between the two blades is broken off.

7. Locate a replacement fuse that is equal in AMPs (which you can tell by the number on the top of the fuse) or 5 amps higher (anything more than 5 amps higher can become an issue in the long run).

8. Replace the fuse by inserting the new fuse into the location of the old, blown fuse.

9. Check that the OBD port is now powered. If it is not, continue checking for blown fuses.


Please contact FleetUp Support at or call 855-274-2886 option 3 for more information.