That's pretty much the reason I wanted to be able to hook it up to a
laptop by a serial cable, so I could see what comes out of that port and
in what order it comes out.
Decompiling the code in the PCM is easier said than done. The only way I
could think of doing that would be if somebody actually wrote a routine
into their software to do a hex dump of the code on the chip. It's very
doubtful they would have done that. So I just gotta keep hunting for the
specs on the protocol that these things use and then start building from
there. I've done it before with other things, I just haven't done it
with an automobile's computer.
Bernd D. Ratsch wrote:
>
> While there's more to it than just reading a code (the basic checks are
> always the first step on check engine lights), not a bad idea if it's less
> expensive....and dash mounted would be really cool to boot! :)
>
> If you're a programmer and can (for better wording)...decompile, "examine",
> and unlock the code (with reference to engine function - fuel, timing,
> etc.)...heheheh....I've got a few spare PCM's you can play with to yank the
> code out and "fix for educational purpose".
>
> - Bernd
>
> -----Original Message-----
> From: owner-dakota-truck@bent.twistedbits.net
> [mailto:owner-dakota-truck@bent.twistedbits.net] On Behalf Of Larry L Athey
> Sent: Thursday, May 27, 2004 10:50 PM
> To: dakota-truck-moderator@bent.twistedbits.net
> Subject: Re: DML: RE: Diagnostic Port Wiring
>
>
>
> I'm not looking to reprogram my pickup, I just want to interpret what
> it's sending out of the diagnostic port so I can write my own software
> that will give me a verbal explanation of the problem (taking the text
> from the DML database) on a small flourescent display. The pickup won't
> be modified in any way, I'd just be adding my own little in-dash or
> under-dash black box to the pickup as a custom built accessory.
>
> Bernd D. Ratsch wrote:
>
>
>>Yup...Base codes are the same - proprietary are different (and there's
>>quite a few of them).
>>
>>As for programming them, without the "unlock" codes (so to speak)...no
>>way, no how to change the parameters.
>>
>>- Bernd
>>
>>-----Original Message-----
>>From: owner-dakota-truck@bent.twistedbits.net
>>[mailto:owner-dakota-truck@bent.twistedbits.net] On Behalf Of
>>david.clement@verizon.net
>>Sent: Thursday, May 27, 2004 3:06 PM
>>To: dakota-truck-moderator@bent.twistedbits.net
>>Subject: Re: DML: RE: Diagnostic Port Wiring
>>
>>
>>
>>I got my cable from this guy; http://www.obd-2.com/
>>
>>Part of the OBD-II standard was that the communication protocols can't
>>be proprietary for the diagnotic functions. All vehicles have to
>>support they same basic diag codes and the manufactureres are allowed
>>to add addtional codes but the base codes must stay the same. Getting
>>into the functional parameters (adjusting timing, A/F mictures, etc)
>>is outside the scope of the OBD-II requirements and that is
>>proprietary to the manufacturer and this is where the DRB tool the
>>dealer has comes into play.
>>
>>The guy listed above was actually on the SAE comittee that came up
>>with the standard.
>>
>>Dave Clement
>>99 SLT+ CC 4x4
>>
>>
>>In article <c94uoa$gcm$1@bent.twistedbits.net>,
>>larryathey.nospam@larryathey.com (Larry L Athey) writes:
>>
>>
>>>Well $150 is a little more realistic...Where did you get the
>>>cable/software from?
>>>
>>>I'm also curious as to where people actually find information
>>>regarding
>>>the pin-outs of these ports and the specifications on the proprietary
>>>protocol Chrysler uses.
>>>
>>>david.clement@verizon.net wrote:
>>>
>>>
>>>>I have an adapter cable that connects to the Diagnostic port and
>>>>serial
>>
>>port of
>>
>>
>>>>a laptop.
>>>>
>>>>There are three different electrical protocols being used by the
>>>>auto manufacturers and none are RS232/V.24. To build a cable you
>>>>need to to have
>>
>>a
>>
>>
>>>>transciever that translates the diagnostic protocol to serial (or
>>>>USB) that your laptop can use. The module in my cable has the
>>>>capability of
>>
>>translating
>>
>>
>>>>all three protocols to serial.
>>>>
>>>>The cable was approximately $150 but it also came with a software
>>>>tool that reads and translates the codes into there definitions, has
>>>>datalogging capabilities and a dash board feature for real time
>>>>monitoring of O2
>>
>>sensors,
>>
>>
>>>>injectors, speed, throtle position, etc.
>>>>
>>>>Dave Clement
>>>>99 SLT+ CC 4x4
>>>>
>>>>
>>>>In article <c93j8h$80s$1@bent.twistedbits.net>,
>>>>larryathey.nospam@larryathey.com (Larry L Athey) writes:
>>>>
>>>>
>>>>
>>>>>Eeegads, they're real proud of their stuff. $275 for a complete
>>>>>package?
>>>>>Geez, a person could build a serial cable for about $10 to $15 in parts.
>>>>>
>>>>>Bernd D. Ratsch wrote:
>>>>>
>>>>>
>>>>>
>>>>>>You can actually buy this type of cable already from several
>>>>>>sources - http://www.obd2.com (is one of them)
>>>>>>
>>>>>>- Bernd
>>>>>>
>>>>>>-----Original Message-----
>>>>>>From: owner-dakota-truck@bent.twistedbits.net
>>>>>>[mailto:owner-dakota-truck@bent.twistedbits.net] On Behalf Of Larry
>>>>>>L
>>
>>Athey
>>
>>
>>>>>>Sent: Wednesday, May 26, 2004 4:55 PM
>>>>>>To: dakota-truck-moderator@bent.twistedbits.net
>>>>>>Subject: DML: Diagnostic Port Wiring
>>>>>>
>>>>>>
>>>>>>
>>>>>>I'm new here, so I'm sure this message has probably been asked and
>>>>>>answered numerous times. Please forgive me if this is redundant.
>>>>>>
>>>>>>Is there any chance at all that I could find out exactly what the
>>>>>>pin-out assignments are on the diagnostic port on a 99 Dakota? I've
>>
>>done
>>
>>
>>>>>>a lot of embedded programming and I've found that a lot of
>>>>>>companies
>>>>>>simply use a 9600 baud 8N1 serial connection on diagnostic ports found
>>>>>>on everything from network routers all the way down to painfully simple
>>
>>
>>>>>>things like home appliances.
>>>>>>
>>>>>>So, what I would like to do is find out if by chance the diagnostic
>>>>>>port
>>>>>>on a 99 Dakota is just a serial connection to the onboard computer. If
>>>>>>so, I'd like to make a serial cable to connect a laptop computer to it
>>>>>>with a basic terminal program running so I can see the error codes
>>>>>>without having to take it to Autozone or a Dodge dealer.
This archive was generated by hypermail 2b29 : Tue Jun 01 2004 - 10:59:13 EDT