Is the C5 CAN BUS or not. OBD2 Fault Code Readers ?

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KevMayer
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Is the C5 CAN BUS or not. OBD2 Fault Code Readers ?

Post by KevMayer »

I thought the C5 uses a CAN BUS for it's various electrical systems and so, when looking to buy an OBD2 engine fault code reader, I've been looking for units that can read a car with CAN.

However, a seller on Ebay told me that as far as he knows the C5 doesn't use CAN but uses ISO protocol.

This ISO may only be for the protocol used by the engine's ECU but now i'm not sure.

Can anyone explain this a little bit further. I'm sure we have the knowledge within the forum.

cheers, Kev
Cheers, Kev

02 plate C5 2.2 Hdi Exclusive SE (now 170k miles 03/21).

Used to have:- Xantia 1.9 TurboD SX. 1996 Blue & 1998 Silver Activa. + 1992 BX TZD Turbo.
Gammy leg
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Post by Gammy leg »

Kev,

Someone on this forum, or the sponsoring company, may be able to help.

http://www.bba-reman.com/forums/



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Post by wheeler »

The mk1 C5 uses VAN/CAN multiplexing,the injection system being on the CAN side of it & the mk2 C5 uses full CAN multiplexing. dont know if that helps any ?
AX_Man
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Post by AX_Man »

What about one of these jobby's. I can't vouch for them but saw them on eurocarparts...

# Portable hand held unit with plug & play interface and single button push for immediate communication with vehicle.
# Fault Code and Fault Code description and Freeze frame data retrieved within 15 seconds.
# 22 vital pieces of diagnostic information displayed on single screen.
# Includes over 22,000 code definitions (manufacturer specific and generic). Complete definition is displayed on screen with the manufacturer of the vehicle.
# Access to Freeze Frame information.
# Erase Code and Turn off “Check Engine Light”.
# Upgradeable for future updates
# Supports J1850 VPW/PWM, ISO 9141, KW2000 & CAN (Including Extended CAN) protocols.
# Specifically designed and created for the European Automobile Market.

http://www.eurocarparts.com/ecommerce/S ... ?Product=1
1996 Citroen AX Debut and 2001 Citroen Saxo.

I love Citroens!
Brian UK
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Post by Brian UK »

AX_Man wrote:What about one of these jobby's. I can't vouch for them but saw them on eurocarparts...

http://www.eurocarparts.com/ecommerce/S ... ?Product=1
At £249 + VAT it ought to be good.
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Bassrock
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C5 Hdi OBD COMPLIANCE

Post by Bassrock »

Hi all,

Be very carefull here, you have to be very specific, first check the pins that are connected on the C5 OBD socket, search google for OBD pinout, that will give you a clue as to the "possible" protocol used, eg KWP200, PWM etc, but this is not 100% accurate. I say this through experience, I have a 2001 C5 2.0L HDi Diesel estate. The OBD conector fitted has a pin config for KWP2000 and ISO. But full OBD compliance is for PETROL 2001 onwards and for Diesel 2004 onwards (So mine ain't strickly compliant). CAN BUS not due for OBD connection till 2008, so I doubt its CAN, although CAN is used on the C5 on the Vehicle network bus, but this is not connected to the outside world.

So far I have used an ELM323 device with scantool software interfacing with ISO and KWP2000 to no avail, e.g. will not communicate, have also used a UIFTECH scantool device which fails to detect any of the protocols.

The only success I've had is downloading ECU MAP data through a KWP2000 interface.

So to summarise, my belief is that Citroen for my car are using a "variant" of either KWP2000 or ISO.

The only devices I'm currently aware of that easily detect and read C5 is the manufactures specific to type test equipment.

So unless anyone out there has a bouthgt device that can read a BOSCH ECU EDC15C2 (nother nightmare area) using KWP2000 or ISO protocol, I would be very interested to hear from you.


Hope the above clarifies ??!!

:-k
Brian UK
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Post by Brian UK »

The compliance dates are the last date that manufacturers can get away with. Many were compliant long before the dates for obligatory compliance. PSA have been using CAN bus since 2004/5 AFAIK.
Certainly several HDI engines vehicles are compliant from '99, (Bosch I believe). The 2000 306 HDI has been tested according to sellers of the ELM323.
KevMayer
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Post by KevMayer »

Bassrock.. have you tried to upload a new ECU file ?

I've seen KWP2000 interfaces for flashing the ECU on Ebay for 99 quid plus postage. Looks tempting but scary at the same time.

cheers, Kev
Cheers, Kev

02 plate C5 2.2 Hdi Exclusive SE (now 170k miles 03/21).

Used to have:- Xantia 1.9 TurboD SX. 1996 Blue & 1998 Silver Activa. + 1992 BX TZD Turbo.
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Bassrock
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ECU upload

Post by Bassrock »

Kev

Mmmm, yip you've a point, tis scary...

6 pints of Tenents and a couple of bottles of a fine malt might tempt me to upload, watch this space..

Naw, having downloaded I can view data (which I could modify, BUT, BUT) and MAPs with WinOls, but this doesn't really tell me anything, e.g I can see the MAPs but I do not know what each MAP represents (e.g function of each), I also do not know what respective data values and constants represent. It's a bit like having a survey map with no longitude latitude or town names to tell me where I am, If I don't know where I am, can't do a lot.

So currently trying to find breakdown MAP of EEPROM download which may give me a clue as to what portion of memory relates to what.

This makes me worry about individuals who purchase MAPs to upload from the likes of ebay, they don't have a clue what they loading. Suppose its the same as handing a fiver to a bloke in the pub who hands you over pills, which you don't have clue what they are, so you take and swallow without asking questions.

Nah unless you know exactly what your uploading and you are 100% confident, don't mess with your ECU data.

Bassrock [-X
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