anti theft fault message 2009 Berlingo Multispace

[jelevents]

Hi still having problems with anti theft message coming up on dash, however I've found if I turn on ignition on then very slightly turn the key but not quite enough to engage the starter the triangle with ! light goes out and car starts fine.
So far I've replaced the transponder ring and ignition switch and tried the BSI reset, neither made any difference, this morning would not start at all with either key so I disconnected battery left it all day reconnected still get the message but now starts again with both keys??????
So I'm thinking perhaps a new key would be the answer, but I don't have the pin code and main dealer or local specialist are booked up till mid October.
Is anyone on here able to plug in to diagnose fault codes I'm based in Bedfordshire but happy to travel a reasonable distance to find the answer?

Update.......I've now changed the com2000 unit on the steering column, made no difference I obtained the pin code took to a citroen specialist he found fault code F4BA but could not clear it, tried recoding the keys no luck then wouldn't start so disconnected battery started ok, but he had no idea what the fault is.
Currently not starting unless battery disconnected and left for while, anybody got any idea/ advise?
Car has done 177,000 miles and has noisy camshaft chain, egr n/w and front suspension lower arm bushes will need doing b4 next mot so I'm thinking it's time to sell it for spares or repair and try to source a replacement?????

[ozvtr]

F4BA code is just a generic anti theft fault and isn't much help in and of itself.
You need to find out whether it's the BSI or engine ECU that's complaining. One of them is not receiving the "go" code. If the BSI is complaining then it's the engine ECU at fault and vise versa. The other line is the Rf coil around the ignition, and the HF unit in the COM's, but you have replaced them. I would highly recommend that you put your original COM's unit back!! It's possible the HF module in the replacement is "incompatible" with your vehicle or non-functional! That would just add another layer of confusion if you were to fix your original problem, but the car still wont start! It's unlikely, but, stuff happens. One problem at a time.

Yes, I know I'm not being much help so far as you need a LEXIA.

You need to supply your VIN and ask Marc (give me a break) nicely for the engine management circuit diagram.

Seeing as "fiddling" with the key initially worked for you, my guess is a power distribution problem. If the instrumentation in the cabin works while you fiddle with the key, then my guess is an engine bay power distribution problem. I.E. the BSI runs power to the instrumentation and dash, so if that doesn't go out then I would assume the BSI has power during the 'start' phase. However, you can't tell if the engine ECU is getting power during the start phase!

The usual suspects are corroded connectors in the engine bay ECU's. I would recommend going over the engine ECU and BSM electrical connectors.
When you get the electrical diagram I would recommend that you check the power and ground connections for the engine ECU. Make sure that the engine ECU is getting power during the starting phase. Next would be power and ground for the BSI. Logically, if you confirm that the BSI and engine ECU are getting power during the starting phase then it's probably a communications error (of some sort). However if you are not getting any CAN BUS errors then a communications problem is unlikely.

If worse comes to worse, pay someone (mechanic, dealership, whoever) to scan the car and get all the error codes! You cant just sit there (metaphorically speaking) and you haven't got many answers from this forum so far.
OOPS! EDIT: F4BA is the only error the "Citroen specialist" found? Nothing else? Did they poll the engine ECU and the BSI? Poll all the ECU to see what they said? The ABS ECU could also be a suspect here. Coms to the engine ECU go through the ABS ECU!

I may be completely wrong but, the "fiddling with the key thing" is all I've got to go on, it's the only clue to work with so far.
Good luck.

[jelevents]

Hi Ozvtr
Many thanks for your response, all very helpful today I removed the engine ecu all terminals are clean and multiplug connectors and wiring all good,
not checked the BSI yet.
There was some other fault codes when the specialist ran his diagnostics but they were to do with egr valve being faulty, I don't think he Polled the ecu but no idea what that means I'm guessing it's sending a message to ask for a reponse.
Lights on the dash all work when I'm trying to start all that happens if I turn the key from ignition on very slightly but not enough to engage the starter I get a clicking sound from the glove box area so must be the BSI so will take it out and see if there are any obvious connection problems, still not able to start as the triangle with ! remains on all the time now whereas before doing the slight key turn would eventually turn off the light and it would start, strangely couple of weeks ago several times the light and "anti theft fault" message did not come on and starting was fine.
I will change the coms unit back to the original as suggested, some people have suggested it's a faulty key but I can't see how that would be both keys to fail at same time, disconnecting battery cured the issue sometimes, makes no logical sense it could be a key?

[ozvtr]

not checked the BSI yet.

Did you mean BSM? The fuse box in the engine bay? That distributes power to things like the engine ECU and can be exposed to corrosion.

I don't think he Polled the ecu but no idea what that means I'm guessing it's sending a message to ask for a reponse.

Yes. There are a number of ways to get information from the car's ECU's some ways don't "talk" to all the ECU's. I don't know what scan tool he used or how he got the information.

some people have suggested it's a faulty key but I can't see how that would be both keys to fail at same time,

I don't think so either. The transponders in the keys are very reliable and to have two fail at once is unheard of.

[jelevents]

I checked the fuse box in engine compartment and ECU all good no signs of corrosion or water ingress

It was a Citroen specialist he used a laptop with I think lexia diagbox.

Thanks again

[ozvtr]

Ok, with LEXIA you can do a "global" scan that gives a list of all the ECU and next to them whether there is a fault or not (yes/no).
You scroll down to the ECU that says it has a fault, then when, you select that ECU it tells you the fault(s).
If it's the BSI saying there is a fault, then the fault is probably between the key and the BSI.
If it's the engine ECU, then the problem is probably between the BSI and the engine ECU.

I would still like to see the circuit diagram and make sure everybody is getting power when they should.

[jelevents]

Another update on fault, I removed the Bsi/fuse box checked all connections couldn't see any issues, car still starting intermittent and when it does start both keys work but the anti theft message still stays on dash??

[bobhoskins]

Did you ever resolve this issue? I'm having similar trouble with my citroen berlingo, 2010. Anti-theft fault showing plus key fob is working intermittently also. Some days the remote fob works and no anti-theft, other days it doesn't. I've done bsi resets many times, changed the key fob battery. Could it be a power issue or bsi/ecu problem? I Have it booked in with citroen in a few weeks but it might not show up then. Any help would be gratefully received as I need this for work and it keeps on failing.

[wheeler]

In your case when the anti theft shows does the engine fail to start?
Do you have a second key to try for ruling out a key issue?

[jelevents]

Hi no I never resolved the issue I sold the vehicle to a guy that said he could program out the immobilizer?
Don't know if he managed to but it's still being used.