Caddilacs With Obd Ii Vs Obd I

[Oldgamer]

As turned out, the Cadillac with OBD II have no some diagnostic help vs. Cadillac with OBD I. I didn't know that, I was sure that they have the same abilities. Now owner can just check computer codes (if they were stored, because how I know now computer sometime can't detect some serious problems). Owner of Cadillac with OBD II CAN NOT check the computer data, computer inputs and computer outputs in diagnostic mode. I'm not sure about overrides, but I guess he CAN NOT make them too.

I don't even talking about "friendliness" of codes. If OBD I code' description was something like "Shorted Engine Coolant Temperature Sensor Signal", now description can look like "Lost Communications With PCM" or something like "Communication Class 2 error". Does somebody know what is class 2 and difference between class 2 and class 1?

I understand that OBD II is a new standard and will be common, but some futures as data, inputs and outputs of computer have nothing to do with that and on board diagnostic can be designed the way which will allow to do it. I believe actually that this still is possible with some "secret button manipulations" or some special tools.

So, now you will visit your Cadillac dealer more often than before. And often instead of fixing your car you will buya new. Who has the benefit of this? I think the same people who don't like you to have "too much" knowledge of your car and how to repair it.

Somebody correct me if I'm wrong.

[Scotty]

Yes I do believe what you say it true, except that I do not believe that OBD2 was developed to make you go back to the dealer, it was developed as a standard for all cars, plus who ever developed the standard did not want you to be able to override settings. NYS just changed their inspection on 96 and newer cars (OBD2), they just plug them in, and read codes, NO more emissions testing. If the system was overridable they would not be able to read the codes with confidence, if you know what i mean.... This was done for consistency if you know what I mean, at our expense..

But look at this program, I am buying it very soon with the enhanced package..

http://www.autotap.com/autotap_for_windows.html

[Oldgamer]

Yes I do believe what you say it true, except that I do not believe that OBD2 was developed to make you go back to the dealer...

Scotty,

please read carefully what I wrote: " some futures as data, inputs and outputs of computer have nothing to do with that and on board diagnostic can be designed the way which will allow to do it. I believe actually that this still is possible with some "secret button manipulations" or some special tools."

I meant that the reason we can do this things is not of having OBD II, but computer diagnostic mode design which is nothing to do with OBD II and a lot of to do with car design. And of course these futures are accessable with special tools. Talking about emissions: that actually calculated based on inputs and can't be overwritten anyway.

This program you talking about... I can't wait... Buy it and tell us how it works!

[Logan]

OBDII is a federal mandate.

The problem was....everyone was calling everything different.

GM car it may be called a 'coolant sensor'...

Honda car might call it a 'thermo load sensor'...

With OBDII. Every sensor has a standard name. IE 'coolant sensor.'

Also, for the most part, with OBDII, all the codes are the same. With OBDI they were totally different between manufacturs...

So with OBDII, a trouble code PO300 on a GM, Honda, Kia, Ford, Toyota etc are all 'random misfire' codes.

Also with OBDII, a standard 16 pin scan tool connection is used by everyone. Before, connections could be found all over the place and required all sorts of special adapters.

You can get vehicle data and codes via the IPC on newer Cadillacs. I know I can on my 2001. Its just not a published procedure.

[KevinW]

I understand that some of the Diagnostic Mode features were removed for OBDII compliance.

[Oldgamer]

Sure, the OBD II as a common standart makes the diagnostic procedure easier for technician who fixes Cadillac today and fixes Honda tomorrow. But it doesn't make it easier to me. As a Cadillac owner I don't care about compliance as much as I care about my comfort.

Logan, I know I can get codes having OBD II. You saying I can get data too. How? Why it's not published? What is a big secret? Should I have a special tools? What about outputs? That's what I'm talking about. They do not make it easier.

[JasonA]

Realize also that the Cadillac cars and the Corvette are among the only cars I know of that let you access the OBD system without any tools. Cadillac has gone out of their way to let you access the OBD without using a scan tool. Sure, you can't reprogram the ECU, but honestly, what do you expect? You have to keep some features away from ignorant owners, lest they screw up their car and have to come to the dealer to fix what they broke. I'm thankful Cadillac gives me a window into the car to see what the problems are. My 2003 Caravan...the only way to know if there's a code or not is to look at the MIL. If it's on, you've gotta bring it in, or hook it up to some type of scan tool. I'm grateful Cadillac invested the time and money to engineer an interface for the DIY owner like us to actually ACCESS the codes without needing special equipment.

I guess you could complain that it's not what it used to be. Me, I'm grateful that Cadillac is ahead of every other vehicle out there in that it's really the only one where you can look at codes yourself, in an easy and non-threatening way.

[Scotty]

I feel the same way. And if it costs me a couple of hundred dollars to buy a program that I can run on a lap top real time while I drive, WOW, I am tickled pink!

I agree though that it was cool that my 91 allowed me to see certain real time actions, it was cool setting the TPS using real time data on the DIC...

I will get that capability again with the program however...

[Oldgamer]

jadcock,

I'm sorry if that looks like complaining to you. I just wanted to discuss some things and to get opinions. Even opposite, you can find my posts when I apploud to Cadillac having this ability [to read codes and more]. Actually, I saw a simple scanning toll for $69 in a local store, but still think that having on board diagnostic is a big thing.

I don't think that reading some data will destroy the car.

"I guess you could complain that it's not what it used to be" - you are right, it is not was it used to be. I have 94 STS with OBD I, and somewhere on a bottom of my heart thought about newer models (specially after something wrong hapenned with my transmission) but the news that cars with OBD II has no some options kinda cooled me off. I guess I just a bit upset

One more: I love my car and I want that later Cadillac's modes became better and better. That's all.

[JasonA]

You can do much more in the OBD-I cars than reading codes. You can turn fuel injectors on/off to check for proper operation for example. I imagine that Cadillac thought later that maybe allowing the customer to manually manipulate the fuel injection system like that was opening themselves up for failure, I don't know.

You can still do a fair amount of neat things with OBD-II. You can program a heck of a lot of features using the overrides. You can directly read almost any input to the IPC, without buffers (like fuel level, digital speed, blinker operation, interior light dimmer pot value, ignition cycles, etc). I admit I'm disappointed that you can't read any PCM data like you can some other body computer data. I feel the inclusion of the system overall is such a benefit to me as an owner that I don't mind the lack of some functions. Perhaps if I started with an OBD-I car I'd have a different opinion.

[Oldgamer]

... Perhaps if I started with an OBD-I car I'd have a different opinion.

I'm sure you'd have it!

I don't know much what I could read on a car having OBD II. Let say I have problem with transmission. I can use diagnostic to check a lot of parameters as input speed, output speed, slippage, pressure switch code, TCC and VCC positions, solenoids positions and more. Just imagine you have ability to see all these parameters too.

I realize how important is that only now, when I trying to make a diagnose. Anyway, it's hard to diagnose, specially because I didn't get any of computer codes and transaxle is a very, very complicated thing.

[Scotty]

This is why I like THIS list of parameters available from Autotap for OBD2:

http://www.autotap.com/enhanced_parameters_gm.asp

Notice these inputs for the tranny that are available, isn't this what you are diagnosing?:

PRND A Input

PRND B Input

PRND C Input

PRND P Input

PRND Position

PRNDL

PRNDL A

PRNDL B

PRNDL C

PRNDL P

[Oldgamer]

This is why I like THIS list of parameters available from Autotap for OBD2:

http://www.autotap.com/enhanced_parameters_gm.asp

Notice these inputs for the tranny that are available, isn't this what you are diagnosing?:

PRND A Input

PRND B Input

PRND C Input

PRND P Input

PRND Position

PRNDL

PRNDL A

PRNDL B

PRNDL C

PRNDL P

Yes, something like that.

It's interesting to know if that software can make computer output some things you want. For example output PO03 will make EGR click if it works fine.