Xantia wont start, Need New ECU

[aneesh84]

My Xantia 1999 2.0 HDI 110 just stopped starting. The engine turns when i turn the key but it wont fire. No symptoms or any other problems I experienced before.

I have had this car for 1.5 years, and ever since I had it, while turning on the immobiliser key light would blink alongwith the beep, but the car would start fine. The light and beep would go away by itself after 30 seconds. I believe it was some kind of immobiliser error. But i never had a problem with it starting excepting today.

Do you think it is because of the immobiliser?

I dont have a lexia but on a standard OBD tool, no errors were found.

I even tried replacing the crank sensor, but still doesnt help.

The fuel seems to be reaching the injectors and the fuel pump can be heard when turning the key.

[aneesh84]

I was having the same problem, as the video posted by mandrake previously.

[CitroJim]

That is an immobiliser problem and most likely a duff chip in the ignition key...

Have you tried your spare key?

Here a Lexia and the CPH confidential code is essential as the first thing you need to do is to see if the ignition key can be re-programmed..

[aneesh84]

That is an immobiliser problem and most likely a duff chip in the ignition key...

Have you tried your spare key?

Here a Lexia and the CPH confidential code is essential as the first thing you need to do is to see if the ignition key can be re-programmed..

Thank you Jim.

Can you explain why the sound and immobiliser alarm was turning off after 30 seconds and the car was starting despite the alarm for more than an year now.

[CitroJim]

Can you explain why the sound and immobiliser alarm was turning off after 30 seconds and the car was starting despite the alarm for more than an year now.

No, except that I know if an ECU is deliberately re-programmed to be unlocked (and therefore not needing the immobiliser), the tone will sound for 30s. Also if the immobiliser is not successfully de-armed the tone will stop after 30s.

I suspect that your ECU may have been in some sort of limbo state where it was unlocked, and thus allowing a start, but not responding properly to the immobiliser.

You need to get a Lexia going on it...

A fairly frequent cause of this issue can be a dodgy engine bay fuse box or a problem in the 10AV loom that runs under the rad which deprives the engine ECU and CPH of essential supplies and signals...

[c.morewood]

I had a one off occurance like this .. stopped at a garage for fuel and she wouldn't start... eventually AA man used an ether based starting aid "cold start" to fire her up .. this worked and I've never had any problems like that again (4 years ago) Worth a try?

Chris

[myglaren]

[CitroJim]

Yours was an odd experience Chris... Makes me wonder, based on your experience if the OP has a new fault that's being masked by the odd immobiliser issue.

Even more reason to get a pukka Lexia on the case.

Steve, I love you picture

[aneesh84]

Yours was an odd experience Chris... Makes me wonder, based on your experience if the OP has a new fault that's being masked by the odd immobiliser issue.

Even more reason to get a pukka Lexia on the case.

Steve, I love you picture

Complicated! I finally towed the car and left it at the Stealers. Lets see what they say on monday. Expecting a hefty bill.

[aneesh84]

My S2 Activa was 'locked out' for over 2 years! I was messing with a lexia on it and just decided to reinitialise the cph as a last resort and .... voila, she started!! Worth a go as a last (or even first if you're a brave man) resort. Just my 6p'worth.

How do you reinitialise the CPH?

[Mandrake]

aneesh: If yours always flashed and beeped for 30 seconds during a normal start, that means two things are happening:

1) Your engine ECU has been unlocked. Otherwise it would be impossible to start with this immobiliser warning. (I found out later my Engine ECU was also unlocked)

2) You have an immobiliser fault. This could be the chip in the key, the transponder antenna (the black sleeve with socket the slips over the ignition lock barrel) or it could be that the CPH is not paired with the Engine ECU. (There are other possibilities too like a wiring fault)

The most likely scenario is that your engine ECU was replaced in the past and rather than buy a new one from Citroen that they could program the immobiliser for they fitted a second hand one that had been unlocked. Thus all along your CPH and Engine ECU have not been paired, hence the immobiliser warning, but because the Engine ECU is unlocked the car still starts.

Your new starting problem is probably unrelated to all this.

[aneesh84]

Hi Mandrake,
What you say makes a lot of sense. The car is still at the Dealer's and they havnt called me back in 3 days, means they are also on the wrong track of suspecting it as an immobiliser problem. I will go there to check what progress they have made.

Since all the red lamps light up including the stop sign, it seems to me the ECU is receiving power signal.

Anyways, thanks a lot for your feedback. i will keep you all posted when a solution is found.

aneesh: If yours always flashed and beeped for 30 seconds during a normal start, that means two things are happening:

1) Your engine ECU has been unlocked. Otherwise it would be impossible to start with this immobiliser warning. (I found out later my Engine ECU was also unlocked)

2) You have an immobiliser fault. This could be the chip in the key, the transponder antenna (the black sleeve with socket the slips over the ignition lock barrel) or it could be that the CPH is not paired with the Engine ECU. (There are other possibilities too like a wiring fault)

The most likely scenario is that your engine ECU was replaced in the past and rather than buy a new one from Citroen that they could program the immobiliser for they fitted a second hand one that had been unlocked. Thus all along your CPH and Engine ECU have not been paired, hence the immobiliser warning, but because the Engine ECU is unlocked the car still starts.

Your new starting problem is probably unrelated to all this.

[aneesh84]

The dealer tested the car by swapping with another unlocked ecu and the car worked. I doubt he has a lexia. Could the logging of faults due to non communication with the cph have filled the ECU thus causing it to stop functioning?

[aneesh84]

Cpu?

Think the fact that an unlocked ecu started the car proves that the original pairing between the cph and ecu had possibly been lost for some reason. I'd still be inclined to find a member on this forim with a lexia and attempt to reinitialise the cph but i understand that with the car out of your hands then you're at the garages call here ... you should have asked whether they had a lexia upfront maybe?

I am in Portugal and here the general level of knowledge of ALL garages is extremely poor including the official dealership. I havnt seen one shop with a Lexia, especially since the newer OBD tools work for all modern cars. Big mistake I didnt buy one earlier.

I have now taken the ECU from the car while the car still rests at the dealership and given it to a specialist who works with ECU. If they can solve it fine, otherwise maybe I will need to order an unlocked ECU and get the car going.

First thing then I must do is order a lexia!

[Hell Razor5543]

Make sure, if you do decide to buy a Lexia, that it has a higher version of DiagBox than 5.29. The Chinese clones have had some of their firmware blacklisted, and can only work with versions up to 5.29.

You must also make sure that the O/S of the computer you are going to use is 32bit, or can have a decent 32bit Virtual Machine with clean access to the USB systems. This is because Lexia is a very old piece of software, and cannot function in a 64bit environment.

Diagbox is a smart piece of software, and will, when the need arises, call up the Lexia or Planet Peugeot software.