What is a good, sub-$300 scan tool?

[guardianangel42]

Hey all, I have a relatively easy question. Recently we've had to send in several of our cars due to the presence of a check engine light and in every case it was simply a faulty sensor of some sort. Now I figure I could change any sensor that's bad myself and save some cash but the problem is I don't have a scan tool to determine the fault.

I could just buy a random scan tool but I'm almost certain that any tool under $100 isn't worth it. I know virtually nothing about them though so I need some input.

I did use an excellent one in high school that ran my car through a full on diagnostic but I figure something like that would be prohibitively expensive.

So basically I need to know either:

*A specific scan tool that has a wide range of compatibility and functions

*Features to look for in my research for a good, relatively cheap scan tool.

 

[4745454b]

Thinking back to my days when I worked on cars....

Most of the cheap (<$100) "scanners" found in repair stores are fine, but they only work on a few car models. If you want it to work on one, then your fine to get it. It will spit out the error code that caused your check engine light to come on. You can assume its a sensor and replace it, but it could be cause by something else. the more expensive "scanners" are able to read more car models. Only difference I ever saw between them.

I'm assuming we are talking about the diagnostic reader you plug into the computer port on your car?

 

[guardianangel42]

Yeah, sorry. A diagnostic tool for reading the computer is what I'm looking for.

We have quite a few cars in varying stages of repair (an '86 mustang, a 1997 Chevy Silverado, a 2004 Chrysler Town and Country, and a 2000 Grand Am) and I would like a scan tool that can read all of them and more.

I also want to know if any scan tool like the ones in Auto Zone, Pep Boys, and the like can read codes other than those generated by the check engine light. I see a lot of reference to the check engine light but I know that the computer can generate codes that don't cause the check engine light to turn on.

 

[4745454b]

Ford, GM, Dodge, GM. You can buy the 3 or 4 tools (the two GMs are close enough in year that it might work on them both, or not seeing as they have very different engines.) or buy the more expensive universal one. Seeing as you have so many cars, I'd get that. Talk to the guys at the stores, they could point you in the right direction better then I could.

 

[sykozis]

Simply put, you're not going to find a scanner that can work with that range of vehicles for less than $500. Part stores like Advance Auto Parts, Autozone and Pepboys sell scanners designed for the OBD2 or Onboard Diagnostics Generation 2 system, but not the manufacturer specific OBD1 systems. You will more than likely have to purchase a tool from the Snap-On or Matco tool distributors to get those capabilities which in general run over $1K.

1995 and Newer = OBD2 (OnBoard Diagnostics Generation 2)
1994 and Older = OBD1 (OnBoard Diagnostics Generation 1)

OBD1 is completely manufacturer specific.

Also, aside from the actual dianostic system in use, you pay for more the ability to retrieve codes from the Supplemental Restraint System (Airbags), ABS (Anti-Lock Brake System) and in some cases the Transmission.

 

[sykozis]

Though the scan tools are available to the general public, please keep in mind that the Supplemental Restraint System aka the Airbags, are not intended to be serviced by the general public as doing so can have very bad results. Improper maintenance of the airbag system can result in very serious bodily injury and in the most severe cases can result in death. The ABS system though, is pretty safe as it consists of sensors, wiring and tone rings, where bodily harm general comes from improper use of tools.