KEYLESS NOT WORKING + ALARM NOW GOING OFF

[C4OAR]

So I've got a 73 Reg Citroen C4 Petrol Automatic.

All was fine this morning, worked as expected. Then, I returned to my car after an hour and it wouldn't unlock. I need to do the manual key, alarm went off, pressed the button. It stopped. Drove as normal. Drove to next location, fob working, open, close, open close, walk away, lock.

Return after 15 minutes, same problem.

Get home, lock the car, come in, 5-10 minutes later alarm going off, wont stop, had to disconnect the negative part of battery till it just stopped eventually.

Waited 10-15 minutes. Reconnected.

This happened with both car key sets. I've changed the battery on the main one.

Anyone experienced this/got a fix? I called dealership... can't see me for 3 weeks. Can't keep having an alarm go off for 5-10 minutes, disconnect battery and wait. Everyone will think I've hijacked the car haha

[mickthemaverick]

It may be worth doing a BSI reset following the procedure in the link below but it may make no difference. Worth a try!!

viewtopic.php?p=601679#p601679

[C4OAR]

Thanks Mick, since reconnecting the battery (25 minutes ago) it hasn't gone back off. I've just gone round the perimeter of the car and the keyless aspect has started working again. I'm hoping that it just needed a reset of it's memory. Previously my dash went all black (about 12 months ago) disconnecting, leaving 10-15 minutes and reconnecting fixed it.

Quite scary not knowing what to do.

How soon after disconnecting the battery should the alarm stop? It went on for about 2 minutes which is forever in a quiet street haha.

I've bookmarked that for future. To confirm a BSI doesn't need a dealer to reset like Citroen suggests?

[mickthemaverick]

As far as I am aware no, you can do it with the procedure in the link, however I am old school and things may be different on the more modern models but not that I know of. The alarm unit does have its own internal battery I believe which accounts for it staying on after you disconnect the main battery.

[PaulC5]

I read somewhere that keyless entry fob batteries do not last long so if it needed replacing in one fob then any other fobs may also need replacing. Something to do with them constantly searching for the car.

[Sloppysod]

I read somewhere that keyless entry fob batteries do not last long so if it needed replacing in one fob then any other fobs may also need replacing. Something to do with them constantly searching for the car.

So batteries don't all go flat at the same time, the way modern (Citroën) fobs work now is that:

• Use it daily no problems - nothing to do.

• If not used for a few days the fob goes to sleep, - proximity unlock stops, works as normal after initial use.

• If not used for longer, it goes into deep sleep - nothing works - you have to re-initialise it by holding it against the steering column while pressing the start button.

You also have to take into account a lazy 12volt battery also has effect on proximity unlocking.

[C4OAR]

So no problems since I disconnected the battery for 10-15 minutes and reconnected. I've requested a battery/vehicle check to see if anything falls under warranty as it's under 3 years old. I typically don't use the car for 5-6 days at a time so that may not help.

Both fobs didn't work yesterday, I changed battery on main one but they both now work the day after... could that be it's now in use or it was a battery?

[Sloppysod]

So no problems since I disconnected the battery for 10-15 minutes and reconnected. I've requested a battery/vehicle check to see if anything falls under warranty as it's under 3 years old. I typically don't use the car for 5-6 days at a time so that may not help.

Both fobs didn't work yesterday, I changed battery on main one but they both now work the day after... could that be it's now in use or it was a battery?

Glad it now seems to of sorted itself, as for the remote battery, that's anyones guess.

[Richard_C]

Anyone experienced this/got a fix? I called dealership... can't see me for 3 weeks.

If I had a spare car in the household I would be tempted to park it outside the dealer showroom with a notice inside the windscreen: "Sorry about the alarm but the dealer can't book it in for 3 weeks"

I had a recall on my 3 month old car last year, earliest it could be done was 5-6 weeks and despite the letter from Citroen saying the check would take 30 minutes the dealer reception insisted on having it for a full day. There s little to do for a day on the industrial estate they are based on. I found another authorised agent who could do it sooner and "while you wait". I've had Citroens for years, decades, but the dealer network has both declined and changed its priorities. It seems that now the priority is to have minimal capacity and have it fully booked, a few years back it was about keeping customers satisfied with the brand so our local dealer (sadly long gone) kept some unhooked 'slots' so you could always get in within a week. I do wonder if I will ever buy another Citroen: cars fine, support pretty poor.

If not used for longer, it goes into deep sleep - nothing works - you have to re-initialise it by holding it against the steering column while pressing the start button.

This is a very good point. My last car -a C4 Picasso, keyless entry and start - had a slot on the dashboard for re-pairing the key(s) if anything went awry. No such thing on the C4, but I was reading the handbook a few weeks back and it mentioned a pad on the steering column that does the same thing. So in case I need it in future I set out to find it - left hand side of steering column low down and close to the far end, cunningly black on a black plastic bit of column. But it is there so give it a try.

Another thing, if you lock the car using the 'blade' extracted from the key it doesn't normally set the alarm (not certain about the C4 but every other car I've owned its been like that) Might help get a good nights sleep. And based on previous experience with other cars, if you do have to get in using the physical key and the alarm goes off you hold it against the 'pad' or in the slot and start the engine within "x" seconds to silence the alarm and reset everything.

[C4OAR]

Thank you for your reply Richard_C! Really helpful.

I'm just waiting for them to inform me of cost to check what is wrong as I'll be amazed if that's not an insane price given mechanics seem to have gone up by nearly 50% since COVID due to 'parts'.

[C4OAR]

When I started the car on Thursday it said it was going into economic mode so I’ve purchased a battery as I feel it leads to that being the problem. If not I’ll do the reset steps for the electrics which was previously suggested.

I’ve only ever had problems with Citroen electronics and my previous cars are Skoda, VW and BMW.

[mickthemaverick]

When you install the new battery you should do the reset anyway.

[Richard_C]

Citroens are always going into "economy mode" but all that means is its shutting down audio and display screens etc to protect the battery. If your recent trips have been short or its stood for a few days then it becomes increasingly likely even if that car is brand new. I think the alogorithm had got a lot more conservative on cars with stop-start as it always wants to be sure it has enough electric power to re-start. A battery should last 5 or 6 years.