Immobilizer

Immobilizer components 1 – immobilizer control module, integrated into the instrument panel housing 2 – immobilizer reading coil. The coil is located on the steering lock housing and is connected to the control module by a cable. 3 – transponder, integrated into the ignition key

The vehicle is equipped with a standard immobilizer system. Once activated, the system prevents the engine from starting if a key with an incorrect code is used.

The system consists of:

– Electronic immobilizer control module (integrated into the instrument panel housing). – Immobilizer warning lamp. – Engine control module. – Reading coil on the ignition lock. – Ignition key with integrated transponder. The transponder is a transceiver unit that operates without a battery.

PROCEDURE

1. The immobilizer is activated when the ignition key is removed.

2. When the ignition is switched on, electrical energy is transmitted inductively through the reading coil to the transponder in the key. The key code is read and sent to the immobilizer control module, where it is compared with the value stored in memory.

3. If the codes match, the immobilizer warning lamp in the instrument cluster illuminates and goes out after approximately 3 seconds.

4. If the codes do not match, the warning lamp flashes with the ignition on and the engine cannot be started. Possible causes include the following:

– An additional key on the key ring interferes with the reading process; – The code is damaged.

5. Electronic immobilizer testing is performed with the AUDI diagnostic tester by reading the fault memory.

Secret Number

On new vehicles, the secret number is found on the key tag. It is required to code a new key.

Identification Number

The identification number is required to obtain the secret number from the factory if it is lost. It is also found on the key tag, but can also be read from the immobilizer control module.