ot -obdII port / scanner / 98 dodge ram

[souNdguy]

I got a 98 dodge ram that has sat unused for a couple months now, and previous to that only started a couple times to move it out of the way of something. I have it setting for sale beside the road..e tc. as luck would have it, and my fault.. battery flattened out.. It wanted to start, but not enough juice.. so i jumpe dit with my tractor.. it started, stalled, then I restarted it and it set a code I guess.. check engine lamp came on. otherwise ran good like it did before.. idled ok, little hesitant at first.. but then it hasn't run in a while.. revved ok.. oil pressure ok.. volt meter said ok.. etc.

anyway.. about the check engine code. I'd like to fix that before selling it, if it is either just a code that set somehow due to the hard start attempts, or if some easy bolt on thing like an 02 sensor.. I'll change it out before selling it. truck is cosmetically rough, but engine has been ok.. i'm selling cheap, so don't want to put a ton of money in it.. but if a 25$ sensor or something.. sure..

I have a cen-tech HF obdII meter I got off a buddy earlier this year for in exchange for some work on his property... still new.. he hadn't even put a battery in it.. he bought it to use, and never ended up using it.. etc. so I got the scanner and it's manual and case etc. anyone know wher ehte port on a dodge ram is.. should be unde rthe dash within a foot of the cluster or so.. right?

otherwise.. any tips or ideas on the code? could the hard start have caused it?

I have the battery out now on a fast charge and will go out and check it in a bit.

tips appreciated... especially from any of you guys that also fix cars for a living..

soundguy

 

[souNdguy]

ok.. so took bat off charge.. had it charging over lunch.. big high dollar console smart charger / booster charger ( 10-20-60-80-250a ) says battery charged and load tested ok.

so put bat back in, truck starts like a champ.. and no CE lamp.

did the code test for stored codes and pending. nada.

i know the bat disconnect may have cleared something.. but 2 subsequent starts and some driving around the property failed to set any more permanent or pending codes.

guess it was low voltage then? didn't even know that was a code option..

soundguy

 

[Bob In Missouri]

I had 2001 Dodge Dakota and could check codes by turning key on-off-on-off-on and codes would display in little window where mileage usually shows. Had 2 codes for misfire in 1 and 3 cylinders. Quick tune up fixed the problem. Sold about 3 months later. Think Dodges around those years have a similar system for checking codes. YMMV Bob

 

[Roger in Iowa]

Like Bob said, turn key on-off-on-off-on but not to start position. May show stored code. Do not need a scanner.

 

[ASEguy]

Some newer Dodge products will display the P code or Powertrain code on the display, but I don't think your year is one of them. You don't have any stored codes because the PCM has a volatile memory which was corrupted with the battery going dead. If there isn't a light on now it's more than likley a performance code which means you have to drive the truck through an OBD-II drive cycle to "arm" the monitors. Without monitors armed a lot of codes will not set. Then when the new owner drives it, and arms them, a code will set. You probably have 6-8 monitors which need to be armed. The dying issue is related most probably to the low battery voltage. That is not uncommon with newer fuel injected vehicles and can be a common warning your battery is low on charge or approaching the end of it's usable life. Hope this helps. Gerard

 

[Hobo,NC]

Yer goat will go into shut down mode if the bat voltage falls beyond a cert'n point even if it has the amps to crank the engine,,, its a voltage thang,,,its why a voltmeter is a valuable diagnostic tool and a OEM dash mounted amp meter is a useless (P.O.S)diagnostic tool 99% of the time...

IF the wallet flush lite is out B happy...

 

[souNdguy]

Ok, did the drive cycle thing ( had to read manual on that one ) and then have done subsequent starts and drives around the property with no CE lamp, no stored codes, and no pending codes?

So did I 'dodge' a bullet? IE.. the code may have been the hard start or failed start / low voltage thing?

soundguy

 

[souNdguy]

thanks for the info.

this code scanner is a neat thing...


soundguy

 

[ASEguy]

A hard start (long crank time) could be something the PCM monitors continously such as cam sensor (CMP) or crank sensor (CKP)which may turn on a check engine light, but it might also be due to a non-monitored condition such as the fuel system and low fuel pressure, which is a non-monitored system. By the way a drive cycle can be completed on most Chrysler vehicles in about 15 minutes, but it's HOW you drive the vehicle not just that you are driving the vehicle. So your drive around the property probably won't arm all of the monitors, but will arm some such as the misfire monitor. Catalyst and heated O2 need continous highway speeds for about 5 minutes to arm. So your light will probably stay out for a little while until the affected circuit monitor is armed. Sorry for the long post. Hope this helps. Gerard

 

[souNdguy]

according to the scanner manual, it had a function to arm all monitors / drive cycle... etc

soundguy

 

[Hobo,NC]

(quoted from post at 12:16:27 10/19/11) according to the scanner manual, it had a function to arm all monitors / drive cycle... etc

soundguy

You have to reset the monitors then when all the stars in the universe line up you run the drive cycles... It can be very time consuming are you can get lucky and get the monitors to run before you get to the end of the drive way...
Any time you have to run more than 2 cycles it does not look good for the home team... I luv those guys that tell ya to drive it 50 miles,,, after you waist a tank of gas with no success folks are more than will'n to pay my fee to fix it....

 

[souNdguy]

so far I've run it a handfull of times now letting it warm, etc. and nothing has come back as set or pending. I'm kinda feeling lucky on this one. it was always a good truck and up until 2m ag was my daily driver. always had periodic maintenacne and anything fixed that broke. always has run good.. etc.

in fact.. that's the only time I've ever had the CE lmap on past the self check at startup.. etc.

soundguy

 

[ASEguy]

That's a new one on me. Every monitor I have ever seen armed was done so through the PCM. Once the enabling criteria is met the PCM arms the monitor. But if you can more power to you.

 

[souNdguy]

Though a cen-tech scanner.. it had a pretty thick manual.. maybee nearly half inch thick.. wasn't the usual chinglish translated type either.. looks almost like they had someone else build the unit / print the manual. nice soft case, has a data hold option and pc cable plus software for it.. good rubber molding on the scanner to protect from dropping and nice 5' detachable port cable... 4 different language options.. etc. and I went and re checked after your email and it for sure says it re-arms those monitors and sets up as a drive cycle, ( if you so chose ) that option.. would also clear codes both pending and set ( if chosen ), and turn off check engine lamp. seemed like it did alot.

I'm sure by commercial standards I's still a 'toy' but for a homeowner, according to google, it's a 120$ retail priced scanner.

soundguy

 

[TheOldHokie]

(quoted from post at 07:54:47 10/20/11) Though a cen-tech scanner.. it had a pretty thick manual.. maybee nearly half inch thick.. wasn't the usual chinglish translated type either.. looks almost like they had someone else build the unit / print the manual. nice soft case, has a data hold option and pc cable plus software for it.. good rubber molding on the scanner to protect from dropping and nice 5' detachable port cable... 4 different language options.. etc. and I went and re checked after your email and it for sure says it re-arms those monitors and sets up as a drive cycle, ( if you so chose ) that option.. would also clear codes both pending and set ( if chosen ), and turn off check engine lamp. seemed like it did alot.

I'm sure by commercial standards I's still a 'toy' but for a homeowner, according to google, it's a 120$ retail priced scanner.

soundguy

Manual not withstanding how can you arm a monitor when the prerequisite conditions have not been met? What does that even mean?

The issue with all of these inexpensive "consumer" scanners is they typically only know the "public" (e.g EPA mandated) codes and are unable to access any ECM's other than the PCM or exercise any of the proprietary OEM diagnostic or maintenace functions. In the case of most vehicles built in the last 15 years that leaves a lot missing! I have a little program for a Windows PC that that will let you manually format any ODB-II/CAN function or diagnostic request you want, send it over the wire, and return you the response. Only problem - nowhere will you find any description of what the OEM data looks like. Consumer loses because there is too much money to be made selling proprietary data CD's to the repair industry :evil:

TOH

 

[souNdguy]

yup.. doesn't handle all the proprietary stuff.

i know it's a consumer scanner.. i didn't expect it to be a 4800$ engine anylizer i got for free for moving a dirt pile and flattening it for a guy during lunch.

as for how to arm a monitor. well.. assuming it's all handled by computer, pcm, and sensors, seems the only thing that is happening is data manipulation, and register setting.. if one computer can do it.. seems like another can as well.

I guess for the people that think I'm plain face lying, i can drag the maual to work and toss on the flatbed scanner and scan as a document and post to prove I'm not making this up ???

soundguy

 

[TheOldHokie]

(quoted from post at 10:00:10 10/20/11) yup.. doesn't handle all the proprietary stuff.

i know it's a consumer scanner.. i didn't expect it to be a 4800$ engine anylizer i got for free for moving a dirt pile and flattening it for a guy during lunch.

as for how to arm a monitor. well.. assuming it's all handled by computer, pcm, and sensors, seems the only thing that is happening is data manipulation, and register setting.. if one computer can do it.. seems like another can as well.

I guess for the people that think I'm plain face lying, i can drag the maual to work and toss on the flatbed scanner and scan as a document and post to prove I'm not making this up ???

soundguy

I don't think anybody has suggested you are lying or doubts that's what your manual says. But I suspect it's overstating the action it's actually performing and I suggest you be cautious on how literally you interprete those words. Based on decades of experience in the computer industry both reading and writing documentation there is no shortage of sloppy language in computer manuals - particularly general user manuals. And that sloppy language has been the cause of many people's confusion when things don't work the way they think they should after reading the manual. At the risk of possibly telling you things you already know and showing my geekyness in the process here is my understanding of how OBD-II scanners (cheap or expensive) and the PCM all work.

The scanner can't directly access any of the PCM hardware/registers or any of the sensors in the vehicle. It is basically a network client program much like the browser you are using to post messages to YT. The scanner simply formats up request data packets and sends them out on the data network (OBD-II buss) addressed to the PCM (network server). Each request packet contains an OBD-II request code. A standard set of codes are defined by the SAE OBD-II specification and OEM's can define their own proprietary (e.g. secret) codes. AFAIK (and I have copies of the pertient SAE OBD-II specifciations and I have read them front to back) there is no public request code to directly "arm" (whatever that means) a monitor. The standard OBD-II reset and clear DTC request codes are about as close as it gets - see monitor description below. When a request packet arrives at the PCM the main loop in the PCM program reads it off the buss and decodes it. The PCM then takes whatever action is requested by the operation code in the request packet and when that operation is complete the PCM formats and returns a response packet containing final completion status and possibly optional response data (e.g. sensor readings) to the scanner. Finally the scanner decodes the response packet and displays the returned status and any optional data in human readable form for you..

"Monitors" are simply little program threads the PCM runs - some continuously and some non-continuously. As the name implies continuous monitors are always running from the moment the vehicle is started. Non-continuous monitors however are scheduled by the thread scheduling software (Task Manager in Chyrsler speak) in the main PCM program and only initiated when the PCM determines the pre-requisites (e.g. drive cycle) for them have been met. A standard OBD-II reset and clear request will typically cause the "Task Manager" to "unblock" any non-continuous monitors it has disabled or put on a scheduling hold due to a latched error. But after a reset those non-continuous monitor threads are not actually initiated until the prerequisite conditions (e.g. drive cycles) for each monitoring function are satisfied AND there are no other conflicting monitors running AND all of the sensors needed to run the non-continuous monitors are functioning properly as determiend by the continuous monitors. So it's kind of indeterminate when they actually get run and/or complete. If you know the scheduling rules for teh vehicle you can make an educated guess but as Hobo says no gaurantee.

Now that's about the sum total of what I know on the matter...

TOH

 

[souNdguy]

I'm ok on the computer stuff. used to beat on old iron inthe 80's. I do know the programmer has about 8 different protocals it can use including the new CAN protocal.

I'll give the manual another lookover, I just breezed thru it to find out exactly what I needed to make it pickup stored and pending codes, and kind of fluttered thru the rest of it, stopping here and there to read a paragraph or tow. I'm certain i read something about it re-arming.. but I'll give it a closer read. I could have completely read over it and got it wrong.. wouldn't be the first time there was a data error betwixt my eyes and brain.. I know I get packet collisions between brain and fingers all the time.

assuming I remember, i'll bring the manual to work on monday and pdf parts of it if I get scanner time.

of course, as you point out.. this all predicates on the ?fact? that the scanner can actually do what it says it can do, based on how the manual was written.

We have another scanner her at work for the powerstroke diesels we drive. they are a scanner and a tuner.. superchips I believe. I'm guessing they do quite a bit more as they are either replacing data tables or possible the operational code itself?

soundguy

 

[TheOldHokie]

(quoted from post at 13:12:52 10/20/11) I'm ok on the computer stuff. used to beat on old iron inthe 80's. I do know the programmer has about 8 different protocals it can use including the new CAN protocal.

I'll give the manual another lookover, I just breezed thru it to find out exactly what I needed to make it pickup stored and pending codes, and kind of fluttered thru the rest of it, stopping here and there to read a paragraph or tow. I'm certain i read something about it re-arming.. but I'll give it a closer read. I could have completely read over it and got it wrong.. wouldn't be the first time there was a data error betwixt my eyes and brain.. I know I get packet collisions between brain and fingers all the time.

assuming I remember, i'll bring the manual to work on monday and pdf parts of it if I get scanner time.

of course, as you point out.. this all predicates on the ?fact? that the scanner can actually do what it says it can do, based on how the manual was written.

We have another scanner her at work for the powerstroke diesels we drive. they are a scanner and a tuner.. superchips I believe. I'm guessing they do quite a bit more as they are either replacing data tables or possible the operational code itself?

soundguy

OBD-II is the data communications protocol (SAE J2178-1 thru 4) that is implemented over a standard 16 pin OBD-II data link cable/connector using one of 4 data link layer electrical specifications - SAE J1850 PWM (Ford), SAE J1850 VPW (GM), ISO 9141-2 (Chyrsler and Europe), and ISO 14230 KWP2000 (Asia). I believe it is also common industry practice to use the ODB-II connector to "flash" the onboard ECM's with firmware upgrades - you just need to know how and that is an extremely well guarded secret. Consider that something as basic as the definition of proprietary OEM parameter ID's used by a scan tool are sold under license for rather hefty prices:

The majority of all OBD-II PIDs in use are non-standard. For most modern vehicles, there are many more functions supported on the OBD-II interface than are covered by the standard PIDs, and there is relatively minor overlap between vehicle manufacturers for these non-standard PIDs.

AutoEnginuity, who manufactures OBD-II scan tools, provides the following example on their website[1]:

Although Ford does implement the largest subset of the OBDII standard, the typical vehicle only supports 20 - 40 [standard] sensors and is limited to the emissions powertrain. Using the enhanced Ford interface, a typical Ford vehicle will support 200 - 300 sensors within half a dozen systems; that's essential systems such as ABS, airbags, GEM, ICM, etc.

Our enhanced Ford interface coverage is only matched by factory tools; we have support for 3,400+ [Ford] sensors selected from all 58 [Ford] systems.

There is very limited information available in the public domain for non-standard PIDs. The primary source of information on non-standard PIDs across different manufacturers is maintained by the US-based Equipment and Tool Institute and only available to members. The price of ETI membership for access to scan codes starts from US $7500[2]

However, even ETI membership will not provide full documentation for non-standard PIDs. ETI state[2]

Some OEMs refuse to use ETI as a one-stop source of scan tool information. They prefer to do business with each tool company separately. These companies also require that you enter into a contract with them. The charges vary but here is a snapshot of today's per year charges as we know them:
GM $50,000
Honda $5,000
Suzuki $1,000
BMW $7,000 plus $1,000 per update. Updates occur every quarter. (This is more now, but do not have exact number)

That is one of the reasons a professional scan tool costs several thousand dollars and the yearly data updates even more. And why I doubt your HF scan tool can do anything other than the standard J2178 PID's.

I beleive CAN (aka CANbus) is both a new differential signaling standard (ISO 15765) implemented using the standard 16 pin OBD-II data link connector AND a new 11 bit data format. CANbus is a general purpose serial bus architecture and has been in use in Europe as well as the USA for lots of other things for some time.

TOH

 

[souNdguy]

reading that listing over Inoticed it mentioned the GEM module.

what a wonderfull 290$ module.. just had to replace one in my 99 f350 7.3 PSD.

one other question. i noticed, again while reading the manual, that it mentions that in case multiple ECU's are listed, choose which one to test. is this a common occurance?

soundguy

 

[TheOldHokie]

(quoted from post at 22:42:22 10/20/11) reading that listing over Inoticed it mentioned the GEM module.

what a wonderfull 290$ module.. just had to replace one in my 99 f350 7.3 PSD.

one other question. i noticed, again while reading the manual, that it mentions that in case multiple ECU's are listed, choose which one to test. is this a common occurance?

soundguy

Edit - went back to through my SAE docs and looks like I've confusd the publication numbers. SAE J1978 is the minimum set of powertrain PID's that all OEM's must support for scan tool use. SAE J2178-2 is the full blown SAE spec that defines the range for all standard (pre-CAN) controller ID's as well as an expanded set of PID's and formatting rules for sensor data from systems other than powertrain. OEM's do not have to support the expanded set of node ID's or PID's and are free to use proprietary ones if they wish.

Modern cars have multiple ECU's: Powertrain Control Module (PCM), Body Control Module,(BCM), Transmission Control Module (TCM), just to name a few common ones. The Ford GEM module is basically a BCM that controls lighting, keyless entry, windows, etc. There is a standard broadcast request to enumerate all ECU addresses on the bus. So a consumer grade scan tool can get the addresses of all the ECU's but isn't capable of accessing much of anything other than the PCM since the PID's and associated data format for the other modules are all proprietary (e.g. secret). The folks that sell my PC based scan tool program also have OEM data for GM and a couple import OEMs at a fairly modest cost. but unfortunately not for any vehicle I currently own I don't know what model HF scan tool you have but I down loaded the user manual for the $140 CentTech Model 98614 CAN/OBD2 scan tool. The list of supported PID's in the Appendix are just the J1978 generic codes for the PCM and I suspect selecting any ECU other than the PCM at setup will get you an error or non response when you try to access it.

According to the manual the 98614 can read DTC's, erase DTC's (which extinguishes the MIL and implicitly resets the I/M Readiness monitor status for all monitors to Not Ready/Not Complete), display "all" PCM sensor data, display real time engine sensor data for up to 18 user selected PID's, graph individual sensor data for a selected PID, set triggers to record user specified sensor data manually or automagically when a specified DTC sets, view freeze frame data stored by the ECU, and show the current staus of the I/M readiness monitors. It has a nice LCD display and useful features like the logging and triggers but is still limitied to the basic parameters.

TOH

 

[ASEguy]

Let me know if you can actually do that with that tool. As I said that would be a new one on me. Gerard

 

[TheOldHokie]

(quoted from post at 04:51:46 10/22/11) Let me know if you can actually do that with that tool. As I said that would be a new one on me. Gerard

I don't know if it's the same model HF scan tool or not but here is all I found in the copy of the manual I downloaded - just standard behavior by the PCM after a code reset.

5.2 Erasing Codes

CAUTION: Erasing the Diagnostic Trouble Codes may allow the scan tool to delete not only the codes from the vehicle’s on-board computer, but also “Freeze Frame” data and manufacturer specific enhanced data. Further, the I/M Readiness Monitor Status for all vehicle monitors is reset to Not Ready or Not Complete status. Do not erase the codes before the system has been checked completely by a technician.

�� This function is performed with key on engine off (KOEO). Do not start the engine.

You can download the entire manul in PDF form here: [u:6b617cff1b]CenTech Model 98614 OBDII/CAN Scan Tool User Guide[/u:6b617cff1b]

TOH

 

[souNdguy]

it's at work and I'm at 2nd job.

Now I got to work on my powerstroke . dodge may take a back seat for a bit..

soundguy

 

[ASEguy]

Our most expensive scan tool which is actually a diagnostic tool is Chrysler's DRB-3 and it cost over $8,700 and it doesn't do that. Better diagnostic tools also allow the user to access and troubleshoot other systems as well like the body controller and work insiden these systems to troubleshoot and set customer preferences. That feature would be a big help in the field. Take care. Gerard

 

[souNdguy]

thanks. plate immediately became full this weekend when the 7.3 stalled on the interstate. hoping was just a fuel issue. and now I've drug home another dern tractor