HELP! OBDCOM Troubleshooting guide


Problems are pretty rare, but as we all know, sometimes the computer just does not cooperate.


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This troubleshooting guide comes from experience helping customers get their OBDCOM system working, so these suggestions really work. If you're having trouble, this should help in almost all cases. Also, please note that we test all of the tools thoroughly before shipping them and that there are many thousands of OBDCOM users all across the country, with all makes and models of cars. It is best to read this guide from beginning to end, and not skip anything unless it says you should skip. Above all else, the first suggestion is to be patient and know that we will solve the problem.


What to do if OBDCOM says "Error 0" when you try to connect to the car:

First try re-installing the drivers from the CD. This solves almost 100% of all drivers installation problems. Just follow the QuickStart guide included with the package to install the drivers.

It still says "Error 0"?

We've encountered many cars with a blown fuse for the diagnostic socket. This is a VERY common problem. Plug the tool ONLY into the CAR, but NOT into the computer. Do you see a red light shining through the sticker? No light means you have a blown fuse in the car. Check ALL fuses. Sometimes it is hard to see a blown fuse. In many vehicles, it is the same fuse as the cigarette lighter or accessory outlet. Note: saying "I remember the red light" is not a valid test. You must RE-DO the above test plugging the tool into the vehicle only, and not into the computer. Once you locate and change the suspect fuse, plug in the tool again ONLY into the car, and look for the red light. If the tool isn't handy, you can also test the vehicle's socket for power, using a voltmeter set to DC range. This photo shows which pins to check: You should measure battery voltage there, approximately 12 volts, or higher while the engine is running. A blown fuse in the car is the #1 cause of Error 0. It's even more common with pickup trucks. Another way to rule out a problem with the vehicle, is to try a different vehicle.

Still getting "Error 0", after trying the above?

With the OBD plugged into the computer's USB port, open up Windows Device Manager and find
in the list. Open that group and look for something called
USB Serial Port (COM#) in the list. (If you do NOT see it, then the drivers need to be re-installed. If you already re-installed the drivers, also make sure the tool is plugged into a working USB port) NEXT: What is the COM# next to USB Serial Port? If the COM# is higher than 15, then first we need to take note of what other COM#s are present on your computer. You can see them in this list there may only be one, or there may be several. Next, double click USB Serial Port (COM#), then click the Port Settings tab, then click the Advanced button, and use the drop-down list to change the port number to something in the 1 to 15 range. Don't pick something that was already taken by another COM# on the list. Windows may say "in use" but that is ok just go by what you saw on the list. Lower numbers are probably a better choice. Often COM2 or COM4 is available, and that's a good choice, but anything in the 1 to 15 range should be just fine. Once you change it, click OK, and give it a try on the car.

Still "Error 0" after trying all that?

Try running OBDCOM as administrator. Here's how: Find the OBDCOM icon on your start menu, and RIGHT-CLICK it. In the popup menu that appears, click Run As Administrator. Windows will ask permission, so be sure to Allow it. Give it another try on the car. This has worked in many cases.


Another "Error 0" fix:

Move your mouse over all the little icons in the "tray".  The tray is the area next to the clock, at the bottom right of your screen.  Each of those little icons represents a running program.  As you move your mouse over them, look at the popup messages.  If one of them says "hot sync" or "palm sync", right click that little icon and exit the program.  Hot sync and Palm sync software interferes with the ports and will result in "Error 0".

You got a "BLUE SCREEN" and Windows shut down when you clicked CONNECT in OBDCOM?

With the OBD plugged into the USB port, open Windows Device Manager and scroll down to Ports(COM&LPT), then open that section up and look for something called USB Serial Port (COM#). What is the COM#? What else is listed there? You probably have other things, each with their own COM number. Option 1: If you set the COM# for USB Serial Port to something in the 1-to-8 range, you can then force the OBDCOM software to use that port in Setup, and put a check in the "Disable automatic port search" box. Option 2: You can disable the other COM ports by Right-clicking on all the other devices with a COM#, and choose "Disable". (This is not permanent.) Don't disable USB Serial Port (COM#), just disable all the others. Option 1 is the best solution. Once you've done one of these two options, try it on the car. The 'Blue Screen' should be gone. If you need help with the 'Blue Screen' problem, please let us know.

You got an Error number in the 100's:
The battery on the car is weak. Try starting the car first to let the battery charge up a bit.
You got an Error number in the 200's:
See the suggestions for "Runtime Error 8021" below.
You got an Error number in the 300's:
Please email us for assistance with this one and mention the error number.
You got Error 1, or the connection status on the computer screen is changing yellow and red and just keeps going on forever?

Make sure the ignition key is in the run position, with all the dash lights on, or you can also try with the engine running.


You got  Runtime Error 75 or 53 or you get no descriptions for trouble codes?

This is a file permission or security issue with windows that can happen on some computers.
You can solve this problem by reinstalling OBDCOM, as follows: 
Use the OBDCOM CD and run SETUP.  You will be asked where you want to install it. The normal place is C:\ProgramFiles\OBDCOM, or something similar to that. 
Get rid of the "Program Files" and anything else, when you are prompted,
and leave only  C:\OBDCOM\   in the box. The purpose of all this is to install OBDCOM to its own private folder, outside of "Program Files", so that windows will not interfere with its files.


You got  "Runtime Error 8021" ?

Cause #1:  Please make sure the connection to the computer USB port is good.  Try unplugging it and plugging it in again a few times.  Then unplug, wait 10 seconds, and plug it back in.   Give it another try on the car.
Cause #2:  Are you using an inverter to power the laptop?  Some inverters make electrical noise and interfere with the diagnostics.  That would cause error 8021, and other errors.

Cause #3:  Are you using a USB extension cable?  How long?  USB cables are not approved for longer than about 16 feet.  Try again without using the extension.

When you plugged in the OBDCOM the first time, there was no "found new hardware"?

Give it a try on the car.  In some cases, the tool can be recognized without any messages on the screen. If it does not work, go to the top of this page.


You really tried all of this and it is still not working?

First, THANK YOU for your patience and cooperation. To help us help you, please email us
(1) the error number you got, (2) the year/make/model vehicles you tried, (3) the windows version, (4) The OBDCOM version number at the top of the OBDCOM window, (5) your full name and phone number, and (6) a description of what is happening. This will help us solve the problem faster and help you to get the system working as quickly as possible. Please don't leave any details out. The more information you can give, the better. If possible, please try another vehicle, and if you have another computer, you could try another computer too.  Remember, we are here to help.