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other person observes the screen on the Tool. Do not attempt to drive and observe
the scan tool at the same time. This is dangerous and puts your life and the lives of
other motors and pedestrians at risk.
Immobilizer (IMMO) Service
An immobilizer is an anti-
theft mechanism that prevents an automobile’s engine from
starting unless the correct ignition key or other device is present. This device prevents
thieves from starting the car by a method known as hot wiring. Most new vehicles have
an immobilizer as standard equipment. An important advantage of this system is that it
doesn’t require the car owner to activate it; it operates automatically. An immobilizer is
considered as providing much more effective anti-theft protection than an audible alarm
alone; many auto insurance companies offer lower rates for vehicles that are equipped
with an immobilizer.
As an anti-theft device, an immobilizer disables one of the systems needed to start a
car's engine, usually the fuel supply or the ignition. This is accomplished by radio
frequency identification between a transponder in the ignition key and a device called a
radio frequency reader in the steering column. When the key is placed in the ignition,
the transponder sends a signal with a unique identification code to the reader, which
relays it to a receiver in the vehicle's computer control module. If the code is correct, the
computer allows the fuel supply and ignition systems to operate and start the car. If the
code is incorrect or absent, the computer disables the system, and the car will be
unable to start until the correct key is placed in the ignition.
The IMMO service can disable a lost vehicle key and program the replacement key fob.
One or more replacement key fobs can be programmed.
