Fault Finding - Function - Renault Duster 2007 Manual

UCH
Vdiag No.: 09
Engine immobiliser
The immobiliser function is divided between three coded computers (the UCH, the injection computer and the key).
Communication between the key and the UCH is ensured by the transponder ring through a magnetic field created
between the transponder ring and the key.
When the + After ignition is switched on, the key sends its identifier to the UCH via the transponder ring, located on
the ignition switch. The UCH runs through an authentication procedure with the key via the transponder ring. If the
key is allocated to the vehicle, then operation of the starter motor is authorised and the injection system is unlocked.
The injection computer has no reference code in its memory: the code which is transmitted is stored.
If the code supplied by the key is not recognised by the UCH, then the system remains locked. The red engine
immobiliser warning light flashes (quickly). The vehicle cannot be started.
IMPORTANT
When the vehicle battery has a low charge, the drop in voltage caused by operating the starter could reactivate the
immobiliser. If the voltage is too low, the engine cannot be started, even by pushing the vehicle.
Recognition of keys in normal operation
Vehicle protected (without After Ignition)
Key recognised, injection protection lifted
Key not recognised, injection protected
MR-453-X79-82D000$040.mif
V1
ACCESS – SAFETY
Fault finding – Function
IMMOBILISER WARNING LIGHT
Indicator light flashes at 1 Hz
Warning light continuously illuminated for 3 seconds
and then goes out
Warning light flashes at 4 Hz
82D-10
82D