Replacement BSI

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My Name: Hans Zarkov

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Joined: Fri Nov 25, 2011 9:59 am
Model: C3 2002-2005, Original shape model
Year: 2004 (04)
Engine Size: 1.4 (16v)
Fuel Type: Diesel
Mileage: 120000
Trim Level: Exclusive
Gearbox: Manual 5 speed


Hello All,

My C3 has developed a BSI fault - the rear wiper relay is flickering, causing the wiper to start intermittently, and stop in strange positions, whethter the ignition is off or on (and causes the alarm to go off in the middle of the night). I know it is not the motor, as I first suspected the position sensor in it, but I have replaced that, and no change.

I have bought a replacement 2nd hand BSI from a scrapper, and have access to a lexia....but I am a bit loathed to swap the BSI 'cos I am worried about the knock-on effect it will have to the vehicle.

Does anyone know what problems I should expect with this change, and how I can get round them? things like the stereo coding, the key coding, the airbags etc :-(

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My Name: C3CAR

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Joined: Wed May 04, 2011 10:01 am
Model: C3 2002-2005, Original shape model
Year: 2002 (02)
Engine Size: 1.4 (16v)
Fuel Type: Diesel
Mileage: 140000
Trim Level: Exclusive
Gearbox: Manual 5 speed
Engine name: DV4 16-valve diesel (90 PS)
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Plan A

If its a faulty relay in the BSI, it will be much easier to have the faulty BSI repaired than have the headache of adding a new BSI. The repair will replace the faulty items and leave the coding, firmware and settings intact. can repair BSI units and will know if its repairable or not.

Plan B and C

If you don't plan to virginise the scrappy BSI, you will need the Engine ECU and keys from the scrap car and fit those. If you go down the virginise route (because its not a 'blank' BSI as you would get from citroen), you will need to wipe to factory (or virginize/virginise) the scrappy BSI to allow lexia to program it up.

I wouldn't worry about the air-bags. The stereo coding and key coding will be covered by lexia. I assume you have the credit card sized security card that original came with the car from the factory as this may be required if you follow the virginise route, not required if you swap all 3 security items - BSI, ECU and KEYS(&TRANSPONDER). You can often find them as kits on eBay (click here)
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My Name: Citroen-Driver

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Model: C3 Pluriel - with or without roof
Year: 2003 (53)
Engine Size: 1.6 (16v)
Fuel Type: Petrol
Mileage: 90000
Trim Level: VTR+
Gearbox: Manual 5 speed
Engine name: ET3 16-valve (90 PS)
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There is a topic on swapping the power board inside the BSI over from a known working unit. This keeps the BSI coding with the engine ECU, keys and the radio, but replaces the complete relay board. This may be your solution, if yours is down to a bad BSI relay and not a bad signal or BSI processing.

The topic is Here - Citroen C3 BSI Repair.
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