On Board Diagnostic (OBDII) - Post 2001 Citroens

David Goddard · Post by **David Goddard** » 01 Dec 2004, 02:09

For some time I had been trying to obtain a cheap system to download engine fault codes for my C5.
I got a lead from Citroen's LaserTec DVD, which mentioned using a Scantool (or similar) to down load diagnostics. A Google search brings this USA made gadget up as about the 1st listing.
They have a couple of UK distributors, one www.gendan.co.uk is advertising them at £89.95 Inc VAT) complete with two cables and the PC software. For Citroens the OBDII / ISO version is required.
I'm very happy with mine it traced an engine misfire to coil no.6 in a flash. It will work on most post 2001 European cars. The makers have lists.
OBDII (on board diagnostics) is required to be fitted to all cars sold in Europe from Jan 2001. Not only that, the protocol (for pollution control purposes at any rate) has to be to a standard. The main one in Europe is ISO, but Ford have a variant, I think GM may have another. This standardization is GOOD NEWS as it enables none main dealers to identify emissions related faults without having to spend a fortune on the car manufacturers’ computer system. You plug into the 16 pin diagnostic socket (on the C5 it’s hidden behind a pull out panel in the glove box), connect through the Scantool interface and then into a PC. Turn on the ignition, boot up the software, and magic - any faults will be reported (by description). It can also turn off the engine management warning light and clear all recorded faults. It will also provide many, many details about the engine’s characteristics whilst it’s running. Other “free” software can be used to log date whilst driving.
The main dealers don't entirely loose out, as they will still have their own protocol for the many other systems (alarms, key coding, a/c and, in the case of the C5, dozens more!).
It will not work on earlier cars.

Post by **Jon** » 01 Dec 2004, 13:39

Hi David,
Thanks for that interesting post. As it happens I too have been looking at OBDII code readers, and have sitting here on my desk an Actron CP9135 Autoscanner which I have recently obtained from the manufacturers for testing, with a view to GSF selling these code readers. I should add to your post, bearing in mind the large amount of Diesel drivers on this Forum, that all diesel cars 1/2003 onwards are also OBDII compliant.
When time allows I will be testing on my Berlingo HDi.
I think that the availability of these cheaper hand held scanners is great news for competant DIY owners.

Technophobe · Post by **Technophobe** » 20 Jan 2005, 00:52

Do you know if my Xantia HDi 110 2000(W) is likely to be EOBD/OBDII compliant ?
If not when did the HDi engines start to support this I/F ?
Technophobe

ItDontGo · Post by **ItDontGo** » 20 Jan 2005, 01:57

Jon a few months back we were developing a fault code reader but decided the time and money was better spent elsewhere. I was wondering how interested GSF would be in this type of thing and also what price range they would be aiming for.
MGB

406 V6 · Post by **406 V6** » 20 Jan 2005, 02:07

Fellas, i have a Scantool, bought in the USA.
It works with 2 Opel we have at home, a 2.2DTI Frontera and my sister's 2001 1.2Corsa.
I've tryed recently on the C5, as i had some suspicions about the MAF sensor, but no deal.
When it went to the dealer, who did a software upgrade for free (it's released every 2 weeks from Cit), he tryed also the scantool OBDII compliant protocol, but the car does not respond to it, only to the proprietary Citroen interface code.
Hope this will do of some help.
Take care!

David Goddard · Post by **David Goddard** » 28 Jan 2005, 03:20

Yes, your GM version of the ScanTool won't work on most European cars i.e. Alfa Romeo, Audi, BMW, Citroen, Fiat, Honda, Hyundai, Jaguar (X300 and XK series), Jeep, Kia, Land Rover, Mazda, Mercedes, Mitsubishi, Nissan, Peugeot, Renault, Saab, Skoda, Subaru, Toyota, Vauxhall, Volkswagen (VW), Volvo, which all (post 2001 use the ISO protocol.)
GM cars use VPW (Variable Pulse Width).
Ford use PWM (Pulse Width Modulation).
ScanTool make all three versions.

rossd · Post by **rossd** » 10 Aug 2005, 13:47

Just resurecting an old thread here... My Elmscan interface (From Scantool) arrived yesterday and seems to work fine with my 1999 306 HDi, both with fault codes and live data (Although the amount fo data seems limited)
I'm using Digimoto 3.7, the only slight problem I'm having is the live data streams only last 10 - 25 seconds but I think thats down to the laptop having very limited memory!
It pulled up a faultcode of Glowplug Circuit "A" malfunction.... (Can't remember the code offhand) does this mean I have a dead glowplug?

jeremy · Post by **jeremy** » 10 Aug 2005, 15:42

Rossd - of course thats the fun of these things - you extract the code and are still not much wiser!
I suppose it means back to basics and test the glowplug circuit. I expect its meant to come of for a period when the key is turned. from older analogue systems this would seem to vary with temperature (Those winter mornings whan I'm late for work and it seems to take forever), later ones stay on when the engine has started to reduce emmissions. So a voltmeter should show if its doing that and disconnecting after say 45 secs after startup.
Glowplugs - back to the old one of disconnecting in turn and checking for resistance which should be negligible.
jeremy

406 V6 · Post by **406 V6** » 10 Aug 2005, 16:34

David, mine is an ISO interface, not GM [;)]. As we don't all live in the Sates, why use an interface practically exclusive to US made cars? [:)]