How to reset Peugeot 306 ECU

Resetting the ECU is a good place to start if you are experiencing strange idle, running or stalling problems. Over time the 306 ECU picks up data from the sensors and 'learns' or adapts to the conditions. By resetting the ECU you will return it to the default settings and remove any 'incorrect adaptations' the ECU has made.

The most common use for this is to reset the Idle Control Valve (ICV) to its default position.

How to reset Peugeot 306 ECU:

1. If you have a standard radio make sure you have the code.
2. Open bonnet and disconnect negative (black) battery terminal.
3. Wait for 10 minutes (maybe time for a really swift cup of tea?)
4. Reconnect battery.
5. Insert keys and turn ignition to second click (all the lights in the dash will light up).
6. Wait 15 seconds or until fuel pump stops priming.
7. Start car
8. Take for a drive covering as many engine loads / rev ranges as possible.

Any questions or comments we'd love to hear about them below.


  1. Will this help me start my car with my un-programmed key?

    1. No but this might