OBD2 Hardware FAQ
Here are some Frequently Asked Questions (and answers) to help you sort through some of
the more confusing aspects of OBD2. We also have an OBD2 overview
available, if you need a little more help. Submissions to this page are welcome, please direct
them to webmaster obd2crazy.com
Which OBD2 interface is the best?
Unfortunately, there is no simple answer to this question.
The manufacturer tools have the most features for their specific makes, but are expensive and
not very flexible. Aftermarket tools specific to a vehicle can come pretty close to the same features,
with a much better price, but still run very proprietary software and aren't universal. Standalone tools
are usually easier to work with, but have limited user interfaces and aren't very flexible. We personally
like the flexibility of the PC/PDA converters, but they have their downsides as well. It is kind of like
asking which vehicle is best, it would depend largely on function (hauling children, groceries, gravel, or just plain
hauling a-- ?)
Where is the OBD2 interface in my vehicle?
Usually under the driver side dash. Here is a
drawing from the EPA website showing the standard
positions. If you are still having trouble, check this
hard to locate interface page.
Why can't I attach a PC directly to the vehicle?
The OBD2 vehicle connecter uses different voltages and modulations then what a PC can handle. It the bare minimum
voltage levels need to be converted.
Will the same converter work on every vehicle?
Although OBD2 is a standard, each manufacturer is free to implement it in their own way. There are essentially
four different types of electrical interfaces. Some converters will handle only one of the interfaces, others will
handle multiple interfaces, some claim to be universal.
Which electrical OBD2 interface does my vehicle have?
If you are going to build your own converter, or buy a converter that isn't universal, you must determine which
of the 3 or 4 types of OBD2 electrical interfaces is in your vehicle. Check our Tech page OBD2 electrical interfaces page
for tips and help in solving what turns out to be a very tough question.