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OBDLink

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Ok gang... I'm going to share a few tidbit of information for advance OBDII tinkering.

 

If you happen to have a OBDLink or ELM327 tool you should be able to tag along here. I will have to give a bit of thanks to @Me78569 for getting me started with the Bluetooth terminal on Android. Once I had that I could directly communicate with the OBDLink and pass commands to it. So starting out I passed the command...

  

ATSP0

This basically tells the tool to communication with the detected protocol of the vehicle ours happens to be ISO 9141-2 protocol. After that I passed the command... 

0100

Which happens to be PID Mode 01 with the PID 00 which tells the vehicle to report back which ODBII PID are available. It returns back. 

41 00 98 3A 80 14
41 00 90 18 80 14

Screenshot_2016-05-27-15-44-30.png

 

At this point the hexadecimal bytes you want are 98, 3A, 90, 18...

 

So now you need to take these 4 bytes on convert them to binary.

 

98 = 1001 1000

3A = 0011 1010

90 = 1001 0000

18 = 0001 1000

 

So now lay it all out in one long string. This is counting 20 hex (32 dec) from left to right.

 

1001 1000 0011 1010 1001 0000 0001 1000

 

So you have counting only the high bit (1's)...

 

01 - MIL Status Light

04 - Engine Load

05 - Coolant Temperature

(11) 0B - Manifold Pressure

(12) 0C - RPM

(13) 0D - MPH

(15) 0F - Intake Temperature

(17) 11 - APPS Sensor

(20) 14 (Unknown yet)

(28) 1C - OBD Compliance should report 05 hex.

(29) 1D - (Unknown yet)

 

NOTE: (number) is decimal... Just for the human side for counting placement. ECM/PCM use the hexadecimal values only.

 

Now if you want to add any of these as a custom gauge.

 

Module/Header: 486

OBD Mode: 01

PID Number: (Any of the above will work use only the Hex number not the decimal)

Priority: Leave on High

Equation: Look it up on Wikipedia at https://en.wikipedia.org/wiki/OBD-II_PIDs

 

Screenshot_2016-05-27-15-46-44.png

 

 

 

Edited by Mopar1973Man

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    boost fooling from the ez.  Remember the obdlink is showing you what the ECM is seeing, the Edge is limiting what hte ecm sees.

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26 minutes ago, Scottfunk said:

Maybe a little off topic here but I reckon it'll get the attention of the right folks here...I just completed my Cummins swap and I'm wiring in the dodge pcm to get through my emissions test. My question for you dodge can junkies is can my Allison tcm and the dodge pcm share the same obd plug? I have already checked and the same pins are used although I am not able to find out if the same pins are being used for the same functions or if that even matters. If they are both hooked up to the same obd will the emissions control equipment initiate communication with the pcm, and the efilive autocal I use to tune my transmission talk to the tcm, or will everything just end up a jumbled mess? I do know my tcm speaks j1939 but I'm not sure what protocol the autocal uses to communicate with the tcm. You guys will know far better than I what protocol is used by the dodge pcm at the obd plug. What do you think?

 

I know you can get a splitter for the OBD2 plug but I'm not sure if that helps you.

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