Technical Anyone had any success with an ELM323/327 interface

Currently reading:
Technical Anyone had any success with an ELM323/327 interface

Argonought

It's about GO! not SHOW!
Joined
Sep 8, 2005
Messages
7,593
Points
1,070
Location
POOLE, Dorset
I've now tried both (one on serial port and the other on USB).

Both provide IDENTICAL garbage readings and both state the Stilo is NOT OBD compliant.

About the only good news is that both can read engine fault codes and presumably clear then (haven't tried that yet).

So far I've tried about 5 OBD type programs and the only thing common is they all report the same identical garbage readings. For example, inlet air temperature is distinctly life threatening at 215C :eek: and coolant temperature is the same :confused: Also ALL say the JTD idles at 211RPM :confused::confused:

I know for a fact Examiner was connected to the OBD interface quite recently to reset the service indicator which would tend to indicate there's not much wrong it (or at least there wasn't :()

Can anyone confirm these actually should work?
 
I've now tried both (one on serial port and the other on USB).

Both provide IDENTICAL garbage readings and both state the Stilo is NOT OBD compliant.

About the only good news is that both can read engine fault codes and presumably clear then (haven't tried that yet).

So far I've tried about 5 OBD type programs and the only thing common is they all report the same identical garbage readings. For example, inlet air temperature is distinctly life threatening at 215C :eek: and coolant temperature is the same :confused: Also ALL say the JTD idles at 211RPM :confused::confused:

I know for a fact Examiner was connected to the OBD interface quite recently to reset the service indicator which would tend to indicate there's not much wrong it (or at least there wasn't :()

Can anyone confirm these actually should work?

just posted about this a couple of days ago on a punto. Fiats use the ISO protocol so should certainly be compatable with the ELM327 which is sort of a 'universal' interpreter and supports most protocols. ELM 323 uses ISO, so should also be compatable.

If the data is garbled, are you sure your using the correct baud rate?
 
Yes; the data stream is readable which it wouldn't be if the baud rate was wrong.

All seem to use 9600 baud, 1 stop & no parity (none of the programs specify stop bits and parity so I'm assuming that's correct - and it's fairly standard (y))

There's a whole mass of reading that just report NO DATA too :confused:

I suppose there's not a different version between Petrol and Diesel is there :chin:
 
yeh AFAIK all ELM chips are 9600 baud. the 327 is 38400 if a specific pin is high during powerup, but 9600 as default - so this depends on how the interface has been designed.

yes your right about the other settings. the ELM chips use 8 data bits, no parity and 1 stop bit.

The punto MK2 and MK2 diesel are both ISO (infact AFAIK all OBD2 compatable fiats are ISO) so i doubt the stilo diesel is any different. all european cars built after 2002 (i think?) have to be OBD compliant.
 
It's almost impossible to advise what to do as you're trying to connect high tech stuff -your laptop- to very low tech -car ECU. As all the programs report connection but unreadable feedback I'd be thinking laptop ports configuration-bidirectional- flow control- that sort of thing but so much depends on your laptop type
 
Last edited:
As all the programs report connection but unreadable feedback I'd be thinking laptop ports configuration-bidirectional- flow control- that sort of thing but so much depends on your laptop type
The thing is the 'feedback' IS readable.

The ECU (or at least the ELM interface) reports no end of "NO DATA" outputs and what data it does produce is wrong (it returns a string of numbers so you could argue it's just interpreted wrong - but it's the same for all programs).

RS232 Comms is not that difficult once you've agreed the basic protocols and flow control.

I don't think there's much doubt that the OBD control program, the OS, the laptop hardware and the ELM interface are all functioning correctly. What seems to be suspect is the communication that's taking place between the ELM interface and the ECU.

I'm wondering about your suggestion of FULLY waking up the ECU. It IS talking but it's not talking very much and doesn't make too much sense when it does talk - although at least it's consistent :)
 
Can you try a different interface?
What port flow control setting do you have it on?
Is this usb or serial port?
Does the interface have leds and are they flashing when comms are taking place?
Are you able to clear codes rather than just being able to read them?
Have you tried your set up on a different car?
 
"Can you try a different interface?"
I've tried two

"What port flow control setting do you have it on?"
Hardware (but makes no difference)

"Is this usb or serial port?"
Both (identical readings from both)

Does the interface have leds and are they flashing when comms are taking place?
Yep; the USB version flashes away nicely :)

"Are you able to clear codes rather than just being able to read them?"
That's my next BIG step when I remove the MAF connector ;) Going to be really :mad: if I can't reset the error.

"Have you tried your set up on a different car?"
Thought of that - but then I wonder who'd like to volunteer :D
 
Well that's it then, your car's not EOBD2 compliant. Ha!:)

If you're passing through there's a few cars here you could try it on.

Or put a sign outside your house "FAULT CODES READING DONE HERE £5 A TIME" Queues around the block

My old laptop connects nearly every time, my newer one is a bitch to connect. Go figure. It seems the newer the technology the harder it is to be backwards compatible. Have you seen the laptop they use in the program "The Garage" ? 2 days to boot up
 
Last edited:
Diesel engines are OBD compliant from +/- 2003 onward - so it's very probable your car is pre-obd.
I use both elm 323 and 327 interfaces on my 2002 petrol 1.6 Stilo without any problems.
In your case it's better to search for a pre-obd diagnostic program for Fiat plus interface.

good luck,
yellowstilo
 
That would make sense but I've now discovered something else.

Just disconnected the MAF sensor and the car didn't bat an eyelid. Even more remarkable it drives just like it has done for the last year :confused:

Just checked consumption driving out of Poole town centre (gradual climb) and it returned 48.3mpg (with MAF sensor totally disconnected :eek:) which I'd say is better than it could manage with it connected.

This discovery would certainly fit with the reduced mpg figures I've been getting over the last year. I've tried everything I could think of but discounted the MAF sensor as Examiner has never thrown an error up (at least not recently).

Reconnected the sensor (definite click when it connects) and the Stilo still didn't bat an eyelid.

Of course, not reading an error code may be due to an incompatibility with ELM interface although you can see the data response by the ECU.

Can anyone confirm for definite that removal of a working MAF sensor will generate an engine fault display on the dash?
 
Well that's it then, your car's not EOBD2 compliant. Ha!:)

my punto mk2 2000 reg is tho, I used a OBD2/EOBD scanner and it connected using the ISO protocol. I would have thought the same system would have been implemented in the stilo? the petrol stilo is definatly ISO.

Argo, I think you should try it on a couple of mates cars (04+ ideally) to rule this out.
 
Had another play today and realized that the programs that 'don't connect' are really connecting but report a bad interface because they can't see an ODB compliant ECU. Many programs report they're seeing an ISO 9141-2(KWP2000) protocol which I presume is much the same as saying they're connected to an ELM interface.

There's only one sensor reading which makes any sense to me and that's from the MAF sensor (but can I be sure that's what it really is :chin:)

I'm seeing a reading of 6 g/s (doesn't mean a lot to me)

Can anyone confirm if this is a sensible reading for a minor blip of the throttle at idle or it nonsense like everything else?
 
I'm seeing a reading of 6 g/s (doesn't mean a lot to me)

Can anyone confirm if this is a sensible reading for a minor blip of the throttle at idle or it nonsense like everything else?

if that's what you're getting at idle speed than it seems to be correct(y)
my 2.4 takes 4-5g/s when idling
 

Attachments

  • OBDGaugeLog.JPG
    OBDGaugeLog.JPG
    19.6 KB · Views: 140
Last edited:
what software have you used argo? which is working best? i sometimes get 'non-obd' errors because they cant detect the cars protocol, but i know the elm327 interface allows force setting a specific protocol rather than autodetecting it. I think the main problem is that alot of this software is designed for earlier versions of the ELM chip which only support a specific protocols and so they don't have to tell the elm to detect it cos it has no choice but to use the protocol the chip was designed for. the 327 however needs to be told what protocol to use or be told to autodetect it. If the software isnt telling it to do either, this may be bringing up the protocol error ive been seeing. if i can find some software that allows me to select a specific protocol, i might be in luck.
 
as said in the other thread argo the jtd seems to run fine with the maf disconnected, i believe the ecu just uses default readings if it cant get one from the sensor. no fault code has ever been thrown up on my car with it disconnected either.

do you have to choose what ecu you have in the car? my mate works at a garage and his diagnostic tool does the same thing, give junk readings. :(
 
I've now tried both (one on serial port and the other on USB).
Both provide IDENTICAL garbage readings and both state the Stilo is NOT OBD compliant.....
Can anyone confirm these actually should work?

I have successfully connected an eBay cheapo USB323 to my 2004 JTD, all the outputs & charts seemed to be reading correctly. I relied upon some advice I'd snipped & saved from a forum (probably this one!), and have pasted it below :

------------------------------------------------------------------

What software are you guys using to read the diagnostics on the Stilo (JTD) and are there any special settings?

I have an ELM323 adapter but it doesn't seem to work using Scantools, ScanMaster or Obd2spy. The software recognizes the ELM adapter ok, but I get "NO DATA" from the ECU.

I can talk to the ECU using the "raw" ELM commands in a terminal session, but only if I use the fast initialization method (ATFI). Using the slow initialization I get -
>ATZ
ELM323 v2.0
>ATSI
BUS INIT: ...OK
>0101
NO DATA

whereas the fast initialization gives-
>ATZ
ELM323 v2.0
>ATFI
BUS INIT: OK
>0101
41 01 00 06 80 00
>

I have also tried forcing the protocol in ScanMaster to ISO 14230-4 KWP (fast init, 10.4 Kbaud) but it still is unable to connect.

I finally managed to get this thing working. For some reason, the ECU ONLY responds when initialized using "fast initialization" method as per the initial post.

I tried using the hardware handshaking as suggested earlier, but this didn't seem to change anything (I don't think the ELM has a RTS/CTS line). I also tried changing the serial buffer size (from 1 byte up to 14) with no success. A USB to RS232 converter to the ELM also didn't work. I even tried a different laptop.

The ONLY thing that seems to work for me, is if I manually initialized the adapter using the "ATZ" then "ATFI" commands.

I can do this with DigimotoLite using the "Serial Interface" tab and also with OBD2 ScanMaster Freeware Edition 0.4.0.0 using the "User definable ELM command" in the terminal window. Once I did that, I could then go back to the start and it seems to work.

There also appears to be a bug in the ScanMaster-ELM demo. Under the communications options, you can select the different protocols (i.e ISO-14230-4 KWP (fast init, 10.4 Kbaud) but it still tries to use the slow init. The demo version has a terminal option, but after you sent the "ATFI" and go back to connect, it re-initializes the ELM and puts it back to a slow init.


Good luck!
 
Just trying to get my interface and software connected to Stilosporting's JTD and it's reporting garbage...almost identical figures to those argo's had.

did we come up with asolution for this?
 
Back
Top