C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

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h2ocooler
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C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by h2ocooler »

Hi All
Not been around for a while as I no longer have a Citroen BUT my dad does, Anyway got a phone call today, his car wont start and its saying immobiliser fault, guessing the ecu is toast (or corroded pins as happened on my old C8) but I need to get him mobile again ASAP (he lives in France in the middle of nowhere)

Looked around for a replacement ECU and there are LOADS of ECU only on ebay, now they all say they need re programming to the car, Is that even possible (I do have a new Lexia with Diagbox 5.8x) and if so does anyone know how to do it?

I have seen a complete ECU, BSI, Key and lock set for it, would that be the better way to go? (I did that on the C8 BUT there is no way my dad could replace all of them, his idea of gently removing something is using a club hammer on it!!!!)

Also I have seen a company that can supply an ECU with the immobiliser deleted (they specialise in HDi remapping) and say it is totally plug and play, no coding required.
I am due to go over there in 2 weeks time but he really needs to be mobile ASAP

Help would be appreciated.
Rob
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by GiveMeABreak »

Hi Rob

I don't know if that's a great idea to be honest.

A couple of things:

1) It may not be the ECU at all - the key may just need repairing which can happen if the battery goes flat or has been disconnected without following the battery disconnect / reconnect BSI reset procedure fully.
2) Ask him to do this first and not to skip parts or timings:

BSI Reset / Battery Disconnect / Reconnect Procedure

3) Your Lexia will be too old for the X7 I suspect - it will need a newer version, and the issue with that is it may not work if you have an older VCI.

See how he gets on with that first.

Your issue will be that the transponder chips handshake with the immobiliser in the car and and the BSI sends an encrypted code back to the transponder to handshake - it it comes back then the BSI talks to the Engine ECU and authorises the car to start - so on the X7 it is a bit more technical that the old vehicles and another reason why I would take what these remap people say with a pinch of salt to be honest.
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by h2ocooler »

My Lexia does work with the X7 as I did connect to it when I first got it for him to check for faults with the suspension, I bought a new one as the old one failed on me.

I will send him the instructions for re setting the ecu and see what happens, Only problem I can see is the car is in economy mode so none of the windows will open and as it cannot be started it wont come out of that!!

He also only has 1 key for the car and didn't get the security code card with it!
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by Hell Razor5543 »

You can get hold of the security code from most Citroen dealerships. They will want proof of ownership (and possibly identity), and they will charge him for it; last time I had to get it I paid around £15.
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by GiveMeABreak »

h2ocooler wrote:
06 Dec 2018, 19:32
My Lexia does work with the X7 as I did connect to it when I first got it for him to check for faults with the suspension, I bought a new one as the old one failed on me.

I will send him the instructions for re setting the ecu and see what happens, Only problem I can see is the car is in economy mode so none of the windows will open and as it cannot be started it wont come out of that!!

He also only has 1 key for the car and didn't get the security code card with it!
He doesn't need the code for resynchronising the key. Once it has been paired it won't need to be done again as a rule. If the battery is in a poor state of charge, I would get the battery charged up too. It can be done on the car - but make sure the negative cable of the battery charger unit is attached onto the battery charge status unit (it will be a square plastic unit that is actually part of the negative terminal connector, and not directly onto the negative post.
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by h2ocooler »

The car battery is new (few months old) as it was replaced when the car was bought.
He has been trying to start it for a while so that is why the economy mode has kicked in.

Regarding the window, could he instead have the drivers door open but use a screwdriver to manually flip the lock mech so the car thinks the door is closed?
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by h2ocooler »

Hell Razor5543 wrote:
06 Dec 2018, 19:33
You can get hold of the security code from most Citroen dealerships. They will want proof of ownership (and possibly identity), and they will charge him for it; last time I had to get it I paid around £15.


Can't get the card over here now as it has bed re registered in France, he might be able to get it over there though.
The registration docs only arrived the day before I took the car over there!!
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by GiveMeABreak »

h2ocooler wrote:
06 Dec 2018, 20:11
The car battery is new (few months old) as it was replaced when the car was bought.
He has been trying to start it for a while so that is why the economy mode has kicked in.

Regarding the window, could he instead have the drivers door open but use a screwdriver to manually flip the lock mech so the car thinks the door is closed?
Ok, so the reason we leave the window open is so we don't wake up the networks when the door is opened - and I assume economy mode is stopping you from opening the window. That should diminish if the battery is charged up though.

You could try that but I'm not sure top of my head where the trigger point is on the door....
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by myglaren »

Is the trigger not in the lock mechanism?
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by xantia_v6 »

My understanding is that you can perform the BSI reset with the door open as long as you don't close it during the procedure, that is to say that there should be no change of state while the BSI is going to sleep or waking up.
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by myglaren »

I have had to take the battery out and leave the car unlocked overnight then replace it with the door open the following day.
Scary but it worked OK.
Not to be recommended but sometimes necessary.

No problem with security as it has this talisman to ward off evil-doers.
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by h2ocooler »

Yes that is right with the economy mode, On his car the economy mode will not go away until the engine has been started and the alternator puts out power, When I first picked the car up the battery was going flat all the time and even when it was charged and up to 13+ volts economy mode was still on.

Will get him to do the door thing and see if the car says the door is open.
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by wheeler »

xantia_v6 wrote:
06 Dec 2018, 21:31
My understanding is that you can perform the BSI reset with the door open as long as you don't close it during the procedure, that is to say that there should be no change of state while the BSI is going to sleep or waking up.

That's correct, a change in status of any of the doors will wake up the BSI, as long as there is no change it wont wake up.

As far as switching on the sidelights goes, I have done literally hundreds of battery reset/disconnect & reconnect procedures on multiplexed cars & switching the switching the sidelights on bit is something I have never done. Once I disconnect the battery (if I'm doing a BSI reset) I always connect a bulb across the battery leads to discharge any residual current before re connecting.
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Re: C5 X7 2.0Hdi Auto Exclusive Immobiliser fault!!

Post by GiveMeABreak »

The side light thing is really only to take out any surges and is something I always do given the sensitivity of and the number of ECUs and circuits on the X7 and most of the newer cars today. It's no hassle and is precautionary, but up to the individual. I always include it for that reason.