Elm327 Bluetooth Obd2 Reader

[aspire_helen]

Hi, I thought I would try out one of those cheap Chinese OBD2 adaptors on my 2001 C5 2.2HDI which displays info via Bluetooth to a tablet/phone app - worth a punt for £3. 

The "mini" adaptor fitted into the OBD socket and, with ignition on but engine off, my Samsung Android tablet connected with it by Bluetooth - so far so good.  I used an app to identify the ELM327 version which it replied with "V1.5".  Of course, V1.5 does not exist as all such adaptors are clones of the original ELM software but at least it proved that my tablet was communicating with the adaptor.

However, I have tried 3 free ELM327/OBD2 android apps and none can connect to the OBD2 system on the car.  The problem appears that none of the 8+ protocols (ISO, canbus etc) work with the car.

Before I waste anymore time on this, has anyone found an app that works? I realise that the EU did not require european diesels to have Obd2 until 2003/4, so does my older C5 have a bespoke protocol? Any ideas?

I note also that a search of all forums does not return any results for "ELM327".

[aspire_helen]

OOpS. That should be ELM 327 !! Perhaps the moderator can amend

[paul.h]

I do not know if this is any help in deciding if it will work on your car http://www.outilsobdfacile.com/vehicle-list-compatible-obd2/citroen

[Randombloke]

I tried an EOBD standard reader with my 2002 C5 2.2HDi after being told by the vendor on eBay it would work with my car, it didn't, and further investigation confirmed that the Engine Management System that far back was not EOBD compliant.

[aspire_helen]

Paul h

Thanks Paul, a very useful link.  It would appear that my car's interface protocol is listed as "KWP FAST" as is many of the C5 variants up to 2009. Elsewhere on the net, it would appear "KWP FAST" is otherwise known as ISO14230-4 KWP protocol - very common.  All the OBD2 software I have used to date tries to connect to the ECU using each of the many protocols (INCLUDING ISO14230-4) but all fail to do so. 

I tried 2 more today - EOBD Facile (the link you gave me) and Scanmaster ELM Demo.  Both are free and permit you to check that their software works before buying a "full" or "pro" version.  Unfortunately neither worked.  Again it is clear that the bluetooth connectivity works OK, and the use of the COM3 port is correct.  They just cannot connect to the ECU using any protocol.

So, I will not pursue further.  Is there any way of canvassing owners of other, more modern, C5s to see if such cheap ELM readers work with their cars?

I wonder also whether there is any link with the issue that many (most?) cheap Lexia downloads dont work with early C5s. Has anyone found an ebay Lexia interface that does?

[paul.h]

There is some Lexia info here, mostly by Simple http://www.citroen-owners-club.co.uk/citroen/topic/23278-lexia-diagbox-pp2000-topics-1822016/

[ESL57]

Was there not talk that only the early cars with Bosch ECU and injection could be read with OBD2 compatibile code readers?

  Some cars have Siemens and Delphi systems?

[coastline taxis]

the elm 327 was our 1st venture into the world of diagnostics. It was a original unit with usb leads and worked a treat on many cars including plenty c5,s.  I think the fault is that its a chinese cheapie and u got it for les than a ice cream so u cant really expect it to do anything  Try a original unit there around £20 and come with leads and software disc and it will work a treat