scangauge xgauge

Bill.Barg · **Posted:** Wed Dec 26, 2007 8:23 pm

I still have not found any xgauge settings for the CRD

bugnout · **Posted:** Wed Dec 26, 2007 9:13 pm

Bill, try sending command 0x0123, if that doesn't work try 0x0122, both should return 2 bytes of data. 0123 should be diesel fuel rail pressure and the 0122 is fuel pressure relative to manifold pressure. I don't think 0122 applies to us, but give it a try.

I've had a little time to play with my scanguage and thought I'd share what I've found so far:

The first byte of the command signifies mode.
01 = Show current data
02 = Show freeze frame data
03 = Show stored trouble codes
04 = Clear trouble codes and stored values
05 = Test results, oxygen sensors
06 = Test results, non-continuously monitored
07 = Show pending trouble codes
08 = Special control mode
09 = Request vehicle information

The second byte requests data for a specific PID

In mode 01 you should be able to retrieve the supported PID's from the ECM. I used PIDs 00, 20, 40 Below is the data from my 05 Liberty CRD.

cmnd 0100 returns bit map of the first 32 PIDs. Mine returned 486B41410C0BDC28, Only the first 4 8bit bytes are data, Not sure what the rest is, may be just the adjacent memory locations.

0x4 0x8 0x6 0xB 0x4 0X1 0x4 0x1
0100 1000 0110 1011 0100 0001 0100 0001

counting from left to right, PID 2,5,10,11,13,15,16,18,24,27,32 are supported. Referencing these PIDS on

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

PID 0x02 or 2 = Freeze DTC
PID 0x05 or 5 = Engine Coolant
PID 0x0A or 10 = Fuel Pressure
PID 0x0B or 11 = Intake Manifold Pressure
PID 0x0D or 13 = Vehicle Speed
PID 0x0F or 15 = Intake Air Temp
PID 0x10 or 16 = MAF Air Flow Rate
PID 0x12 or 18 = Sec Air Status
PID 0x18 or 24 = Short Term Fuel Trim
PID 0x1B or 27 = Short Term Fuel Trim
PID 0x1F or 32 = Run Time Since Start

cmnd 0120 returns a bitmap for the second 32 PIDs. Mine returned 12021 which is only 3.5 bytes rather than the 4bytes I was expecting.

0x1 0x2 0x0 0x2 0x1
0001 0010 0000 0010 0001

counting from left to right, PID 36,39, 47, 52 are supported. Referencing these PIDS on

PID 0x24 or 36 = Equivalance Ratio Voltage
PID 0x27 or 39 = Equivalance Ratio Voltage
PID 0x2F or 47 = Fuel Level Input
PID 0x34 or 52 = Equivelance Ratio Current

the last 8 bits are for Catalyst temp, probably doesn't apply anyway, but I would have expected a 0 to be tacked on

cmnd 0140 should return the bitmap for the third set of 32 PIDS, but returns nothing and causes the SGII to do some strange stuff. The gauge screen still works, but a number of the characters are scrambled after I run this. I have to shut off, unplug then replug and start to get it to return to normal operation.

Anyone have any ideas? or can reproduce my testing so far?

geordi · **Posted:** Wed Dec 26, 2007 10:51 pm

I consider myself a computer guy, but I'm not sure what screen you were in to send that data. On mine, when I go to the command entry screen, it wants me to choose a memory location. Ok, did that. But I can select up or down for the command... But only 1-9 and A-F... Not x. So I entered 0123 like you said... And got back 01232 as a reply. That doesn't seem to make any sense to me... What did I do wrong?

Key on, engine running, scanguage with latest FW 3.15 (as it was a Christmas gift, brand new)

Can this be made into an X gauge to read the rail pressure all the time? If so... How?

bugnout · **Posted:** Wed Dec 26, 2007 11:14 pm

geordi wrote:

I consider myself a computer guy, but I'm not sure what screen you were in to send that data. On mine, when I go to the command entry screen, it wants me to choose a memory location. Ok, did that. But I can select up or down for the command... But only 1-9 and A-F... Not x. So I entered 0123 like you said... And got back 01232 as a reply. That doesn't seem to make any sense to me... What did I do wrong?

Key on, engine running, scanguage with latest FW 3.15 (as it was a Christmas gift, brand new)

Can this be made into an X gauge to read the rail pressure all the time? If so... How?

You did it correctly, 0x just means that the code is in hexadecimal rather than decimal format.

ok so 0x01232 is the returned data from your query. The formula for pressure then is ((A*256)+B) * 10 kPa where A is the first byte and B is the second byte.

A=0x01 or 1
B=0x23 or 17

(1*256 + 17) * 10 = 2730 kPa

Theoretically, you should be able to get a snapshot of the instantaneous fuel rail pressure using this technique. Hopefully with the xgauge feature you can monitore it more regularly. I'm not sure if this is accurate, I don't have xgauge yet to see if it tracks with what the CRD is doing.

bugnout · **Posted:** Wed Dec 26, 2007 11:39 pm

Again, the return results from 0122 or 0123 are dubious since when I retrieved PID 0120, it didn't include 22 or 23 as supported PIDs, Just thought someone with XGauge might try them.

Would someone try 0120 and see if it returns the same 12021 I got?

hawk521 · **Posted:** Thu Dec 27, 2007 12:04 pm

Bill,

I'll try to do some testing with xGauge feature this weekend. At the moment I am up to my eyebrows with year-end inventory here at work!

Have not used xGauge beyond the ability to create a trip parameter as an xGauge displayable value. Will have to roll up my sleeves and see if there is anything I can do. The DashDyno SPD can retrieve the Fuel Rail Pressure - so obviously it is out there. I might be able to decipher the data comm log file to see what command it is sending to retrieve the Fuel Rail Pressure. But I will preface that attempt by saying that they have gone out of their way to make this stuff unintelligible! lol

KJMedic · **Posted:** Thu Dec 27, 2007 10:30 pm

OK my scan gauge keeps showing a p1267 code. I can't find out what it means. Do any of you know?

CATCRD · **Posted:** Thu Dec 27, 2007 10:33 pm

http://www.lostjeeps.com/forum/phpBB3/vie ... light=1267

bugnout · **Posted:** Sun Dec 30, 2007 12:18 am

bugnout wrote:

Again, the return results from 0122 or 0123 are dubious since when I retrieved PID 0120, it didn't include 22 or 23 as supported PIDs, Just thought someone with XGauge might try them.

Would someone try 0120 and see if it returns the same 12021 I got?

Has anybody given this a try?? 0120 is supposed to return a 4byte bitmap of the supported PIDs. Just want to see if this return is just my CRD or everyone gets the same result back.

Luc.Blais · **Posted:** Wed Jan 02, 2008 12:26 pm

When I sent 0120, I got this back "486B184111170B" hope it helps

bugnout · **Posted:** Sun Jan 06, 2008 4:14 pm

Luc.Blais wrote:

When I sent 0120, I got this back "486B184111170B" hope it helps

Thats very interesting. Could you try 0100 as well?

bugnout · **Posted:** Thu Jan 10, 2008 12:58 am

Ok, Did a little more experimenting and a little more research and discovered that entering the PIDS alone won't work. Need to have the full ISO OBDII request formated.

CRD uses ISO format commands -- If you set the MODE to auto then check MORE>MORE>MODE to verify that it defaults to ISO

the CMD format is as follows

h1h2h3xxxxzz where
h1 is the type of message
h2 is the Target Address
h3 is the SGII's Address
xxxx is data and is where the PID should be entered
zz is the checksum byte

Each mode has different values for H1H2H3, but ISO (the CRD's mode ) uses the following to request info from the ECM: 686AF1xxxx

So to send the command to determine what PIDs 0x01-0x20 are supported (PID 0100) send 686AF10100

When I sent 686AF10100 I got the following result: 486B124100983B0011EA

486B12 is the header, the third byte indicates that the ECM is at address 0x12

4100 indicates that its a response to request for PID 0100 -- Could be a response to a different request, if you dont get 4100 just repeat until these bytes are correct

983B0011 is the data returned
EA is the checksum byte

The data represents a bitmap of the supported PIDs which translates as follows
9 8 3 B 0 0 1 1
1001 1000 0011 1011 0000 0000 0001 0001. each bit represents a supported PID

so PIDs 1,4,5,11,12,13,15,16,28,32 are supported

1=Number of trouble codes and I/M info
4=Calculated engine load value
5=Engine coolant temperature
11=Intake manifold pressure
12=Engine RPM
13=Vehicle speed
15=Intake air temperature
16=MAF air flow rate
28=OBD standards this vehicle conforms to
32=PIDs supported 21-40

PID 32 can be queried to determine if any additional PID's beyond the first 32 are supported.
Since 32 decimal = 20 hex we can send 686AF10120 to get the second set of supported PIDS
This cmd returns 486B124120A0000000C6 so the data is
A0000000
A 0 0 0 0 0 0 0 0 0
1010 0000 0000 0000 0000 0000 0000 0000 0000 0000

so PIDs 21,23 are supported
21=Distance traveled with malfunction indicator lamp (MIL) on
23=Fuel Rail Pressure (diesel)

so PID 23 seems like what we want for xgauge to allow us to monitor fuel rail pressure. The cmd to query the instantaneous value should be 686AF100123

I don't have xguage on my SGII so if someone could give this a try we might be in business.

Goglio704 · **Posted:** Thu Jan 10, 2008 4:34 am

Thank you for the hard work. I wonder if the miles traveled with MIL is a cumulative value or if it clears with the MIL?

Jeger · **Posted:** Thu Jan 10, 2008 9:25 am

Goglio704 wrote:

Thank you for the hard work. I wonder if the miles traveled with MIL is a cumulative value or if it clears with the MIL?

Yeah....me too. If its cumulative I have several 10's of thousands of miles recorded :shock:

bugnout · **Posted:** Thu Jan 10, 2008 11:04 am

Jeger wrote:

Goglio704 wrote:

Thank you for the hard work. I wonder if the miles traveled with MIL is a cumulative value or if it clears with the MIL?

Yeah....me too. If its cumulative I have several 10's of thousands of miles recorded :shock:

Sould be cumulative, the maximum value that can be reported is 65,535 kilometers
The PID is 0121 so the cmd to query the value for the MIL is 686AF10121

The return value I got after starting (MIL light on for ORM) was 486B124121000027 so A = 00 and B = 00 which would be expected. formula for Distance Traveled since MIL is (A*256)+B kilometers I will try again on my way home from work, should get about 17 miles or 28 km

I also queried PID 23 fuel rail pressure and got back 486B1241230CE015 -- A=0C B=E0 or A=12 B=224

formula for fuel rail pressure is ((A*256)+B) * 10 so my idle fuel rail pressure was 32960 kPa from a max reportable of 655350. This is gauge pressure so I think its a relative measurement rather than absolute. I'll query again on my way home while I have my foot in it to see if it tracks.

Bill.Barg · **Posted:** Thu Jan 10, 2008 1:11 pm

Bugnout,

The Xgauge requires the following input ?!?

TXD RXF RXD MTH

TXD command that will be transmitted to the vehicles computer.

RXF This screen is the entry for the receive filter. This value tells the
ScanGaugeII what to look for in a response from the vehicle computer.

RXD This screen tells the ScanGaugeII where the data and its size in the
response

MTH This screen tells the ScanGaugeII the math needed to scale and/or offset
the value received XGAUGE entry screens.

where other enhanced data looks like
http://www.scangauge.com/support/pdfs/XGAUGE.pdf

The value you want checked seems to be the TXD part. What should i use for the other inputs?

Bill

Bill.Barg · **Posted:** Thu Jan 10, 2008 1:39 pm

I got this from an inside source.
I am not sure how it fits in with what you have found, Bugnout

Trans Oil Temperature
Identifier: $EA
Byte: 2
Bit: 7..0
Rate: 3584

Fuel Temperature
Identifier: $D1-01
Byte: 6
Rate: 2700

bugnout · **Posted:** Thu Jan 10, 2008 10:01 pm

Give me a chance to do a little reading and I'll see what I can do.

PID 0121 worked differently than I thought. Its zero unless the MIL light is on, counts up while the MIL is on, and is zeroed when you reset the MIL.

PID 0123 looks like it tracks fuel rail pressure correctly.

Goglio704 · **Posted:** Thu Jan 10, 2008 10:17 pm

bugnout wrote:

PID 0121 worked differently than I thought. Its zero unless the MIL light is on, counts up while the MIL is on, and is zeroed when you reset the MIL.

That is good news.

Joe Romas · **Posted:** Sat Jan 12, 2008 1:35 pm

I've been reading about this and the 327 chipset has most all OBDII standards covered. Does anyone here use it? The software is both commercial and open source. the hardware is around $75 US.
http://www.alpha-bid.com/page15.html
I have VAG-COM for my VW's and it will do the basic OBDII stuff on the liberty along with rail pressure and a couple more but I would like to do more. On the VW TDI's VAG-COM can reduce EGR, raise idel change fuel mixture and more within certain limits.

Joe

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