OBDLink LX and Android Tablet

[TFaoro]

To simplify the learning curve I started with the 1996 Dodge Ram 1500 with only the PCM to find. I've got to say "SUCCESS!" I figured out how to address a simple gauge like "Tachometer".

Screenshot_2015-04-14-11-48-32.png

 

The 1996 Dodge follows the PID listing for the ISO 9141-2. Take notice the module/header is 104. This is decimal for hexadecimal 68.

 

Now to move over to the diesel and try again... Then dig deeper into the dark corners of that ECM (Evil Laugh)... I'm going to keep moving forward.

 

Like what I found in the SAE doc...

saej2178.png

Good work Mike!

BTW I see the music you are listening to up in the corner

[notlimah]

Ummm... You are too quick to give up. How about...

 

http://www.obdlink.com/mxwf/

 

Designed just for Apple products (iPhones, iPads, etc.)

 

Oh nice! Looking forward to seeing where this goes!

[Mopar1973Man]

First off let me be very very clear about something. OBDII information will not add more gauges than there is sensors for. So if people are looking to replace conventional gauges with OBDII directly it's not going to to happen. Being fuel pressure and EGT's are not part of the ECM sensor array.

 

So that being said I want to learn how to dig out the hidden bits of data that are floating around the ECM & PCM like fuel temperature and Transmission temp. Those would be a nice addition and goal to reach for.

 

As for what I know. I know that both my 1996 Dodge Ram (Gas) and 2002 Dodge Ram both use ISO 9141-2 (5 baud init, 10.4k baud). The refresh rate is roughly 4.2 PID's per second. I know that out of the standard OBDII data there is 10 known PID's for the 2002 and 14 PID's for the 1996. Being the 1996 is a 46RE automatic I should be able to tap the transmission temp sensor and get the fluid temp. Then on the 2002 Dodge I know the VP44 has the fuel temp sensor and modules like Quadzilla and Edge both can read this data from the OBDII port. The biggest thing is doing all the reading of SAE and different OBDII standards. Bad part is Cummins did NOT follow the OBDII rules so the extended data is going to be a bit tricky to find. Now are a rule of thumb most manufactures changed from Mode $01 to Mode $22 for extended data. But like after doing my study work for the past two days finding Toyota uses Mode $21 for extended data. So this just makes addressing a bit tough. So I've been digging into ScanGauge II and seeing similar things of data and addressing. That's what gave me the break I needed was looking around and finding header address 68 6A F1 used on most ISO 9141-2 even if you look close you'll see ScanGauge uses the same thing.

 

http://www.scangauge.com/support/x-gauge/xgauges-for-iso-vpw-vehicles/

 

Which now looking again tonight as I type this. I starting to understand the ScanGauge II X Gauge format in rough layout. TXD (Transmit Data), RXF (Receive Filter), RXD (Receive Data), MTH (Math). So after the ELM 327 document you'll see how the ScanGauge II does the data search for the information and displays it. But to keep the confusion down I like the Android Tablet idea much better because your working with human readable information and not strictly Hexadecimal like ScanGauge II.

 

 

So now just look at (link below) and look over the Mode $01 data. This is what most tools like ScanGauge II are capable of seeing. Now If you got the talent for ScanGauge II and Hexadecimal then you could follow along and get the extended data to work also.

 

http://en.wikipedia.org/wiki/OBD-II_PIDs

 

Now open this up and flip to page 15. These PRN's are the extended data hidden in the ECM.

SAE J2178_2v002.pdf

 

Like PRN 102F is engine oil pressure, PRN 1044 Fuel Temperature, PRN 180B on page 16 is Transmission Temperature. Just going to take more study time.

[bjytech]

I got to thinking and I have access to cummins insite at work so I looked to see if there was a simulator for the 24v on it and sure enough there was one for the chrysler cm551(24v), I can't get any PID's off it though (don't even know if they would be any good for what you are working on anyways even if I could see them since to hook insite up to the engine in a dodge you use a under hood harness plug(3pin) not the OBDII port) but anyway here is the list of parameters that would be reported from the ECM to insite in live data monitoring.

Edited April 15, 2015 by bjytech

[Mopar1973Man]

I see that the fuel temperature shows up on the Cummins Onsite but its limited to just the ECM. Lots off good data there just limited to Cummins Onsite.

[Explosives87]

I think that I was going to buy a scan gauge so I could clear and trouble shoot codes but now I think that I am going to buy the ob2 mx scan tool so that I have the ability to read gm also. Does it tell you what the code is in the app or do you still have to look it up?

[Mopar1973Man]

On the software it will do the look up over the internet for you as well. So it gives a P number and brief description and then you can do a look on the internet of more information. I'll see if I can produce a few screen shots for you.

[dodgedieselnewbie]

I just got one of these... Is there a tutorial on how to set it up? I have no codes.. yay! 

It says "not available" for VIN  

Do I choose "Direct Fuel Rate"?  Volumetric Efficiency???

[Mopar1973Man]

Hmmm... What choices do you have for fuel rate?

VIN is available on later years of trucks. Our is buried in a special hidden area.

[dodgedieselnewbie]

in the vehicle editor I see mass air flow rate, intake absolute pressure and direct fuel rate. Which should I choose and what does it mean? volumetric efficiency is defaulted at 65

[Mopar1973Man]

Ok. Direct fuel rate for our trucks. As for the volumetric that is your offset to adjust the MPG number to get calibrated. As you change up or down it will change the MPG number for offset.

[eddielee]

After looking at this I searched Cummins on Google play and they have their own app fault code adviser. Read and manage public j1939 fault codes and other data from your cummins engine.

Once you install the software it asks you to link to bluetooth obd2 device.

Edited January 3, 2016 by eddielee