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ELECTRICAL
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IMMOBILIZER CONNECTOR & PIN OUT DETAILS
PIN
SIGNAL NAME
INPUT / OUPUT
LEVEL
CLASSIFICATION
1
Vbat (KL30)
ICU PWR
POWER
150 mA
2
GND
ICU PWR
POWER
150 mA
3
CAN - H (HIGH-SPEED)
COMMUNICATION
--
--
4
IGN (KL15)
INPUT
HIGH SIDE HIGH ASSERTION, 2-20 mA
5
STATUS LED
OUTPUT
LOW SIDE
LOW ASSERTION, 2-20 mA
6
LOCKSET ILLUMINATION INPUT
HIGH SIDE HIGH ASSERTION, 2-20 mA
7
TRANSPORT MODE
INPUT
HIGH SIDE LOW ASSERTION, 2-20 mA
8
CAN -L (HIGH-SPEED)
COMMUNICATION
--
--
Key ring illumination
Immobilizer earthing
PIN
SIGNAL NAME
PIN
SIGNAL NAME
1
KEY RING SUPPLY
1
IMMO GND
2
GND
2
IMMOBILIZER WORKING PRINCIPLE
The EMS ECU and the immobilizer are paired together by an encrypted secret code called as “AES secret
key”, to improve the security of the vehicle. This AES secret key is generated using the vehicle identification
number (VIN) and it is unique for each vehicle. Both immobilizer and the EMS ECU are programmed with
same secret key for mutual authentication. If any one of EMS or ICU has different/ wrong secret key, vehicle
will be locked (engine cannot be started).
If EMS or Immobilizer is changed in a vehicle, it is required pairing operation (EMS ECU & ICU programmed
with same secret key) for proper mutual authentication. The pairing of EMS and Immobilizer can be done
through diagnostic tester.
These E-keys are learned for that immobilizer and are unique to that Immobilizer & vehicle. The E-key of other
vehicles will not work with this immobilizer and vice versa.
If anyone of the E-key is lost, it is recommended to approach TATA AUTHORIZED dealer for new E-key. It is
possible to learn new keys with the help of diagnostic tester (Refer the key learning procedure). If both the
keys are lost, it is not be possible to learn the new keys for that immobilizer, as original key is required during
E-key learning operation.
IMMOBILIZER SYSTEM STATUS
During Ignition off, immobilizer status bulb (“Lock” symbol on the instrument cluster) blinks, indicating
Immobilizer is awaiting E-key.
When the ignition key is turned to the “ON” position, if the status bulb goes OFF indicates that the
system is working and the vehicle is unlocked (Engine is ready to start). If the status bulb is continuously
ON, there may be something wrong with key or with the immobilizer system.