whats your favorite scan tool

I use this one

on my laptop. It gives me the ability to save the scans on the laptop for future reference. It also has excellent support and constant updates.

I bought an Actron 9135 (I think it has less built-in info than the 9145) because it was the least expensive device ($160) that looked like it met my needs... at least when I needed it. I only use the reader occasionally, but it sure is useful when I need it!

The code CD that comes with the reader seems useless, though. Their website is more up-to-date and easier to use.

Mike

"Woody" wrote in news:I2%1e.15676$ snipped-for-privacy@newssvr17.news.prodigy.com:

Seems to me that some smart person could make a OBD scanner adapter/SW package to work with a Palm pilot or similar handheld PC. An inexpensive adapter.

Jim Yanik wrote in news:Xns9627CAC64A8BBjyanikkuanet@129.250.170.86:

They do. Lots and lots of them. Google is your friend.

Here's one:

"TeGGer®" wrote in news:Xns9627D35FBFBEAtegger@207.14.113.17:

And a useful link here:

Do I understand this right: One downloads the appropriate software for the car of interest?

If so, very slick!

Remco

Software I was impressed with from;

Made for Palm OS machines or PC computers.

Remco wrote:

OBD-II is actually three separate protocols: ISO, VPW, and PMW. Your car uses just one of these three. Inorder to be compliant to OBD-II the device must be able to interface to each of the three protocols.

I suspect taht ISO, VPW, and PMW are lower layer protocols that are just responsible for getting the "OBD-II content message" (i.e., trouble code X) transmitted from the vehicle to the reading device. The code itself is universal across the three protocol (e.g., trouble code 1011 (made up) means speed sensor malfunction over each of the three protocols).

Many of the cheap PC versions of the interface require the user to purchase a cheap interface card (under $100) that supports just one of the three protocols. So it is technically not a certified OBD-II device. Then there are an assortment of free and non-free programs that you can use with the card.

Each manufacture has extended OBD-II interface and will have codes that are unique to that manufacturer. I believe you can get access to these online but if not the service manual should theoretically have the codes.

OBD-II is quite limited in that there are just a few operations that can be invoked. Examples include: a) fetch code, b) run a test c) clear code.

Many (all?) manufactures have extended the interface to allow other operations. One program allows you to send any command but you basically have to figure out the binary representation of the command. Theoretically this is dangerous because it is error prone and the specs probably arent published.

I wonder if you can reload the firmware of the engine control module this way?

I'd be surprised if any software can make the interface work without the hardware, because the connector and voltage levels are not compatible with any normal pc hardware. Usually the card does the hardware adaptation and changes the message to a byte-oriented protocol the computer can deal with.

I opted for a stand-alone tool because I don't have a laptop or PDA handy and I don't foresee the need for logging, etc.

Mike

OBDII dictates the EPA code in the computer. It does not dictate the protocol used to communicate with the test tool. That is why there are three different types. ISO is used by Chrysler and most foreign cars, VPW is used by GM, and PMW is used by ford. A device with only one of these is still OBDII compliant for that car line. Most will attach to all three, some you pay extra for each connection type. All car manufacturers put a lot of diagnostic code in their systems above the compliant code. Most consumer scanners do not have the ability to get this proprietary information. There are some that can get some of the information but they get expensive. That said for the majority of the home users the consumer products work fine. Just make sure the one you get covers the car lines you expect to use it on.