Immobilizer on 308SW

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dram773
Posts: 36
Joined: 30 Apr 2024, 10:41
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Immobilizer on 308SW

Unread post by dram773 »

Afternoon all,

On unlocking parked car suspicion immediately aroused by wing mirrors flashing but not folding out. Switched on ignition and dash lit up like an Xmas tree with bells and Engine Fault etc. No starter. Again.
Last time this happened, breakdown service told me the immobilizer had locked out. He solved it by simply disconnecting the battery for 30 secs and reconnecting it (to my horror, without following the recommended reach through open window, turn on side lights etc. procedure). All warnings gone and started fine.
So rather than wait 2 hours for a call-out, I simply tried the same technique - and it worked :-D
I won't ask why it throws out Engine Fault when it is an immobilizer problem - life is too short. But does anyone know what causes this immobilizer problem? The mechanic suggested it might need a software update, but given the above simple work-around I'm not inclined to throw cash at the local dealership.
Hope the above may help anyone encountering the same annoyance.
RichardW
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Joined: 07 Aug 2002, 17:12
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Re: Immobilizer on 308SW

Unread post by RichardW »

I doubt this is an immobiliser problem, my guess is that the battery protection unit is at fault, and is not powering the car up properly. Taking the battery off may shock it into life. Really need to read the codes and see if there is anything about the relay not latching.
Richard W
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Arkis
Posts: 92
Joined: 14 May 2022, 11:14
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Re: Immobilizer on 308SW

Unread post by Arkis »

This seems more like a BSI unit or battery protection unit failing. Also make sure your battery is in good condition. Weak battery or bad grounding points can make france electronics go wild.
Last edited by Arkis on 03 Apr 2025, 18:24, edited 1 time in total.
Citroen C4 Picasso 2013, 1.6 e-HDI 85kW
Peugeot 206, 2005, 1.4i 8v, 55kW
dram773
Posts: 36
Joined: 30 Apr 2024, 10:41
x 4

Re: Immobilizer on 308SW

Unread post by dram773 »

Having replaced the BPGA some time ago, that was my first thought when this happened. But simply disconnecting and reconnecting the battery made no difference to the BPGA problems, which progressively got worse over several weeks before reaching the stage where the starter wouldn't turn. Diagbox is showing no errors but local garage did full service last week and so may have cleared the cache. The breakdown guy seemed confident that it was the immobilizer - apparently he gets lots of similar call-outs with Stellantis vehicles. Anyway, I've got a spare new BPGA so I'll try that if/when it happens again.