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Robert, Peugeot Technician
Category: Peugeot
Satisfied Customers: 4716
Experience:  Fully qualified 19+yrs exp/self employed technician in the UK
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I av a 307 iv change the battery to day now it won't start

Customer Question

I av a 307 iv change the battery to day now it won't start just turns over
Submitted: 3 years ago.
Category: Peugeot
Expert:  Robert replied 3 years ago.


Hopefully i can help..

If you havent done the 3 minute rule disconnection and reconnection then it possible you need to run through the bsi reset which i highlight below..

Peugeot are fairly sensitive to battery changes/jump starting - if the correct procedure isnt followed then you can run the risk of corrupting the bsi software or loosing key coding where the vehicle immobiliser simply wont shut off hence the engine wont start... Try the 3min rule again and then follow the reconnection procedure below..failing that the only way forward from that is to get it diagnosed to exactly whats gone wrong the likely hood the immobiliser isnt picking up the keys or a problem has surfaced in the bsi due to the battery fault.power surge or spike..

Unplugging battery

  1. Before unplugging the battery, turn off all gadgets and lights, closing all the doors and unplugging any kind of diagnostic tool. The drivers side window has to be kept open kind of requirement.
  2. Turn off the ignition and take out the key following which unplug the battery after an interval of 3 minutes.
  3. The BSI needs to be taken to Sleep mode or Active Economy mode, during which nothing in the vehicle should be operating. Even the bonnet should not be opened that time as it can ‘wake up’ the BSI if the vehicle has got an alarm installed. under the bonnet, the bonnet should be opened and left up before allowing the BSI to go to Sleep Mode. During this 3 minute interval, use of any remote control central locking gadgets vehicles should be avoided in the vicinity of the concerned vehicle.

Reconnecting Battery

The following procedure is the battery connection unless told otherwise by Peugeot or Product service. Failure to follow this procedure may result in damage to the BSI’s embedded software during reconnection.

  1. All the doors have to be closed with the ignition key turned off and the key taken out.
  2. Now without opening the doors, replug the battery and wait seconds.
  3. Turn on the headlights, turn on the engine and inspect the system’s functioning.

BSI start up

  1. The very first step is to unplug the diagnostic tool from the vehicle.
  2. Make sure all the gadgets are switched off, the driver’s window lowered down and open the bonnet
  3. Then close all the doors and take off the key from ignition.
  4. After a 3 minute interval, unplug the vehicle’s battery terminals and wait further 15 seconds.
  5. Attach back the battery terminals and give a 10 second pause making sure the doors are closed.
  6. Turn the side lights on
  7. Now turn the engine on and inspect the system functioning.
  8. Press and hold down the lock button on the key seconds
  9. Check the central locking system by unlocking and locking the door consecutively.
  10. Turn the engine on again and finish inspecting the system

So as above give that a try - failing that the only alternative is the diagnostic route to see whats happened if the BSI has been damaged or lost key sync which can be quite common..I do hope this helps