Immobiliser bypass help

Talk about the 406's electrical system, what wires do what, how to add extra functionality, etc.

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sollude
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Immobiliser bypass help

Post by sollude » Fri Oct 12, 2018 12:12 am

Morning all,

I have been working on my father in laws 1998 406 Estate that has developed a seriously bad misfire. Now having spent a lot of money for a retired man he was looking to get rid.
Done the usual fuel filter, coil pack, plugs tested etc. Now from doing my homework I believe there is a possible ECU issue so I bought one on ebay came from a 2.0 but with a pin immobiliser. Now it fits and cranks but doesn't fire I'm assuming immobiliser.

Plenty of how too's on the hdi engine almost nothing on the 2.0 petrol. Can someone please help with advising how to bypass the immobiliser.

sollude
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Posts: 4
Joined: Fri Oct 12, 2018 12:06 am

Re: Immobiliser bypass help

Post by sollude » Sat Oct 13, 2018 12:53 pm

Anyone able to help?

frog
2.0 16v
Posts: 169
Joined: Sun Aug 24, 2014 12:18 pm
Location: Netherlands

Re: Immobiliser bypass help

Post by frog » Mon Oct 15, 2018 2:28 pm

Do you see an orange key icon light up on the dash?

Not sure for the '98 models, but on the later models for sure the ECU is matched (paired) with the BSI box and a set of keys. They must be replaced together.

In your case i think the keys are not coded, since you have a PIN pad.

Easiest solution is if you can get hold of a complete set (ECU, BSI, PIN pad) and replace them all at the same time.
Current "fleet":
2003 406 Estate 2.0HDi 110 - 7 seater
2001 Citroen Saxo 1.6i 8v 100

Previously owned:
2000 406 Sedan 2.0 HDi 90
2000 406 Coupé 2.0i 16v 138 - Riviera Blue

PP2000 user, can help with faults / diagnostics in the Netherlands.

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GingerMagic
3.0 24v
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Joined: Fri Apr 06, 2012 9:02 pm
Location: Bournemouth

Re: Immobiliser bypass help

Post by GingerMagic » Mon Oct 15, 2018 2:58 pm

I'm pretty certain that once the car is started then you can unplug the keypad ( with the engine running ) and it will bypass it.

However, this doesn't answer your problem about getting it started in the first place - have you had a chat with a Peugeot dealer to see if there is a way of finding it through serial number on the ECU, or the eBay seller giving you the registration number or VIN number?
1999 T4 family wagon
2005 Vauxhall Meriva
1998 406 V6 Coupe - Midlife crisis..!
PP2000 user, can help with faults / diagnostics in the Bournemouth area.

jasper5
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Joined: Fri Nov 28, 2008 2:30 pm

Re: Immobiliser bypass help

Post by jasper5 » Mon Oct 15, 2018 6:09 pm

I remember from the old days when we used to get these in for service and the customer hadn't left their keypad number....1111 always got them running, it's a default service pin.

sollude
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Posts: 4
Joined: Fri Oct 12, 2018 12:06 am

Re: Immobiliser bypass help

Post by sollude » Tue Oct 16, 2018 9:34 am

Good morning all,

Thank you all for your help on this.

Sorry just to clarify the current car doesn't have the keypad. The ECU I bought spare came from a car than had an key code.

frog
2.0 16v
Posts: 169
Joined: Sun Aug 24, 2014 12:18 pm
Location: Netherlands

Re: Immobiliser bypass help

Post by frog » Tue Oct 16, 2018 10:07 am

sollude wrote:
Tue Oct 16, 2018 9:34 am
Sorry just to clarify the current car doesn't have the keypad. The ECU I bought spare came from a car than had an key code.
The ECU will need the keypad.

You might try to hack the immobilization codes out of the ECU EEPROM. Inspiration may be found here.
Current "fleet":
2003 406 Estate 2.0HDi 110 - 7 seater
2001 Citroen Saxo 1.6i 8v 100

Previously owned:
2000 406 Sedan 2.0 HDi 90
2000 406 Coupé 2.0i 16v 138 - Riviera Blue

PP2000 user, can help with faults / diagnostics in the Netherlands.

sollude
Newbie
Posts: 4
Joined: Fri Oct 12, 2018 12:06 am

Re: Immobiliser bypass help

Post by sollude » Tue Oct 16, 2018 10:58 am

Awesome so If I remove the Chip it should allow me to bypass the immobiliser.

frog
2.0 16v
Posts: 169
Joined: Sun Aug 24, 2014 12:18 pm
Location: Netherlands

Re: Immobiliser bypass help

Post by frog » Tue Oct 16, 2018 11:37 am

Could be :wink: i've never done it so i have no experience with this.
Current "fleet":
2003 406 Estate 2.0HDi 110 - 7 seater
2001 Citroen Saxo 1.6i 8v 100

Previously owned:
2000 406 Sedan 2.0 HDi 90
2000 406 Coupé 2.0i 16v 138 - Riviera Blue

PP2000 user, can help with faults / diagnostics in the Netherlands.

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