2015 C4 Picasso alarm/BSI problem

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AlanB1971
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2015 C4 Picasso alarm/BSI problem

Post by AlanB1971 »

Hi folks
Hit a bit of a snag with the wife's car. Had to disconnect the battery while doing some work on the car last week.
After finishing the work I discovered a problem, which I can only assume is caused by incorrect disconnection of the battery, in turn causing a corruption of the BSI.
The problem is, whenever the car is locked using the fob, the alarm sounds immediately.
If the car is then immediately unlocked using the fob, then it turns off the alarm and unlocks the car. If left, the car will then auto lock within a couple of minutes, but this is a far from ideal way to lock the car. Plus, I can't be sure the alarm is working at this point.
I've tried resetting the BSI, even leaving the battery off overnight, and I've tried the trick of locking and unlocking the car with the actual key, all to no avail.
Anyone got any ideas on what will be required? Is it main dealer only?
Thanks in advance for any help.
Cheers
Alan
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Re: 2015 C4 Picasso alarm/BSI problem

Post by Hell Razor5543 »

Hi, and :welc: to the forum. I would first check that the work was done has been done properly. I assume that the alarm/central locking was working properly before the work was done? What was the work that needed doing?
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GiveMeABreak
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Re: 2015 C4 Picasso alarm/BSI problem

Post by GiveMeABreak »

Use the BSI Reset / Battery Disconnect / Reconnect Procedure for future reference.

To lock the car without the alarm (internal or exterior), just lock or deadlock the car with the key, not the fob.

Try disabling the internal volumetric protection by disabling the ultrasonic sensors in the car to determine if it is these that are setting off the alarm. So just after switching the engine off and within 10 seconds, hold the alarm deactivation button until the red light comes on then exit the vehicle and lock the car as normal. See if that stops the alarm going off. If not then it's not the interior sensors and maybe that the alarm module needs replacing.

But in either case locking with the key only as I described earlier should disable the activation of the alarm.

I replaced ours in the C3 after ours kept going off after disabling the ultrasonics - The internal battery on these can die after years of use, so if the main car battery is weak or there is a break in the current, there may not be any backup supply in the alarm ECU battery to maintain the circuit / or it may be triggering the anti-tamper if it thinks the supply has been cut.

You didn't mention what work you had done, but if it was anything in or near the glovebox, where the BSI and the fuses are, then be aware that the Alarm module sits above this, so if any wiring has been dislodged or pulled, it may be enough to cause problems.
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Re: 2015 C4 Picasso alarm/BSI problem

Post by RichardW »

Is the bonnet and all the doors shut properly?
AlanB1971
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Re: 2015 C4 Picasso alarm/BSI problem

Post by AlanB1971 »

Thanks for replies. Everything in the car was working fine before work. The work had nothing to do with bsi etc., it was just some work on rear brake calipers. I did one side and everything was fine, but I'm guessing I didn't allow the bsi to switch off before I disconnected the battery for other side.
The alarm literally sounds as soon as you arm it, it's not something triggering the alarm as far as I can tell. I'll check the interior sensors when the wife gets back with the car.
Locking the car with the key works, but not sure if the alarm is armed using this method, plus its dead fiddly. And I've checked all doors are closed etc. I have heard of this happening to someone in the past, and was fixed by the bsi being updated by main dealer.
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GiveMeABreak
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Re: 2015 C4 Picasso alarm/BSI problem

Post by GiveMeABreak »

Locking with the key in the lock prevents the alarm from arming, which is why I suggested it, to get you out of a fix. It’s all in your owners manual.

If it still activates then you have something else going on or it’s a coincidence that the alarm module may need replacing.
AlanB1971
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Re: 2015 C4 Picasso alarm/BSI problem

Post by AlanB1971 »

Cheers Marc
the doors lock fine with the key with no alarm activation, it's only when locked from the fob.
I have spoken to a local diagnostics guy, who is happy to have a look at it, and if he can't fix it he doesn't charge.
Can someone other than Citroen re-install the software on the BSI?
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GiveMeABreak
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Re: 2015 C4 Picasso alarm/BSI problem

Post by GiveMeABreak »

No, it won’t be that. The software doesn’t disappear on the BSI or become mid-configured once written. All a battery disconnection without allowing time for the various ECUs to shut down properly will do is possibly leave them in a state of half awake half asleep. Undertaking another reset as per procedure will clear this.

You may also have a faulty door or bonnet sensor that could be triggering the alarm. I would not let anyone loose on your BSI as even when configured by internet via PSA servers they still need programming with optional equipment and other parameters which will cause you more problems most likely.

A dealer will diagnose it first as the alarm triggering will be logged. Depending on the fault it will likely be a new module or sensor or a check of the electrical connections. How old is your Picasso? If it’s anywhere near 10 years or older then it’s very possibly the module.
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Re: 2015 C4 Picasso alarm/BSI problem

Post by UpsetPicasso »

Hi! I am reading this post thinking you must be driving my car as this is exactly what is happening with mine at the moment. I have tried turning off the internal sensors as mentioned above but the alarm does still sound. This is one of a multitude of problems my 2008 C4 Picasso is suffering from at the moment so if anyone does have a theory, knows a good therapist or can offer a push in the right direction it would be amazing!
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GiveMeABreak
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Re: 2015 C4 Picasso alarm/BSI problem

Post by GiveMeABreak »

Hi and welcome.

The alarm can go off if you leave the windows open of course as the volumetric sensors can be triggered by air movement. If this is happening while the car is locked and happening a lot of the time, then it will very likely need a new alarm module. These have a battery backup, but like all rechargeable batteries, they have a finite life, so when they don't hold a charge they start tripping when the voltage drops enough - similar to when somebody cuts the supply.

I've replaced a few of these now and a new module has fixed the problem. A diagnostic may not help in this case as it is a temporary fault , but it will just keep logging the triggering.

So if the alarm keeps triggering even after deactivating the internal sensor protection with the button after switching the ignition off, then I would suggest the module needs replacing.