elm or can bus

[monkfish]

hi lads or ladettes i would like to know if i need a elm cable or can bus cable to connect to my ecm or are they both the same as i have some diagnostic soft ware that i would like to use if poss many thanks for any info

[Paul-R]

You don't give the year of your C5 so I will say possibly but probably not. The others are much too old for EOBD standardisation.

[CitroJim]

The Xantia and BX are neither; Citroen proprietary and only readable with a Lexia or similar tool specially designed to read a pre-2001 Citroen.

I'm afraid I cannot be any much help on the C5 but again, the very best tool for the job is the Lexia. A cheap ELM323 OBDII interface might give some generic fault codes but these do not necessarily have the right meaning on a C5.

[monkfish]

my car is a 51 c5 2.2 hdi i know that most of the diags wont do every thing that a lexia can do but i just want to use this as a starting point

[CitroJim]

A 51 plate diesel may be too early to be OBDII compliant. By law petrol engines had to be by 2001 but diesels did not need to be until 2004.

It's really a case of "suck it and see" Can you borrow an ODBII reader to se if it'll work?

[cachaciero]

A 51 plate diesel may be too early to be OBDII compliant. By law petrol engines had to be by 2001 but diesels did not need to be until 2004.

It's really a case of "suck it and see" Can you borrow an ODBII reader to se if it'll work?

My understanding (which could be wrong!) is that OBDII only covers engine ECU's and in this respect the C5 is I believe compliant. The problem comes with all the other ECU's many of which have K lines and CAN bus that come out on various pins reserved for OEM's, there is as far as I know no standard for this because they are OEM specific and there is no global spec for these.
So in summary an ELM may / should do the engine ECU diags but that is actually a small proportion of the total on a C5 for the rest well only ELM may know the answer.

cachaciero

[enginostics]

Hi, just thought i'd leave this message. We specialize in fuel injection systems and we are based in the North West of England. I must say, i have worked with people in the past developing software around the Elm chip. We use state of the art equipment as we are a business. The hobby systems based around the elm chip are very very basic. There is a piece of software called Proscan 5.0 which works great with the elm based interface buy there are limitations. It will only work with petrol cars post 2001 and derv cars post 2004. There are the odd vehicles that will work outside the stated spec but you'll struggle.

[monkfish]

thanks as i said i only want to have a crack at simple stuff first before i get a lexia buy the way i had 2 alfas both 156 before my c5 and a coputer boff on there site managed to write a diag program called alfadiag witch i have and it did every thing that alfas main steelers diag did cost 55 quid with life time updates could some one on here not do the same