Peugeot 406 Parking lights.

Created: 1.03.2008
Updated: --.--. ----

Peugeot 406 D9 2001
Built: 08-Jun-02
Electrical structure: Multiplexed BSI, Passenger compartment fuse box BH28, Engine compartment BM34.

Front and rear parking lights (side lights) not working.
The instrument illumination works and the light on warning operates when the lights are
switched on and the key removed.

General comment:
Finding this fault proved to be difficult due to the inadequate documentation of
this particular circuit. That's why we made some notes of the most important points
needed to trace the fault. This information was provided by a kind peugeotlogic visitor
who would like to share his knowledge with other Peugeot owners.

Faulty BSI. No power output to BH28 fuse 20 and 21.

Replaced the BSI.
Replacement of the BSI requires programming of the new unit and learning of all keys.
The learning and programming can only be done with the assistance of the Peugeot diagnostic computer.

Fundamental diagnostic information
The following parts are involved in the circuit for the side lights.

  1. BSI, that's the main body computer.
  2. Black 16 way connector on the BSI. (16V NR)
  3. BH28, that's the fuse box in the passenger compartment.
  4. Black 36 way connector on the fuse box. (34V NR)
  5. IC 11A 16V NR, that's a black 16 way connector under the carpet near the accelerator pedal.
  6. 2 Head lamp units with 1 black 6 way connector each. (6V NR)
  7. 2 tail lamps with one white connector each. (6V BA)
  8. Fuse 20 and fuse 21 in the passenger compartment fuse box

Basic functioning of the system

Circuit diagram.
Please excuse the quality of the temporary sketch. It should however show the most fundamental points of the circuit needed to find a fault.



Work on a motor vehicle's electrical equipment should only be performed by qualified auto electricians.
Damage can be caused to the electrical system if correct procedures are not followed.
We do not advise car owners without necessary skills to attempt their own repairs.
The above instructions may not be applicable for your particular problem. It is up to you to decide if these procedures should be applied to your vehicle or not. Use these instructions at your own risk!

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