Page 1167 of 1184

IMMOBILIZER ANTI-THEFT SYSTEM 9T–15
DAEWOO M–150 BL2
DTC 1600 – ECM Immobilizer Error (No Answer)
StepActionValueYesNo
1
Connect the scan tool using the following procedure:
1. Insert the cartridge into the scan tool.
2. Turn the ignition switch to the OFF position.
3. Connect the scan tool to the data link connector
(DLC).
4. Connect the scan tool’s power cord to the cigar
lighter socket.
5. Turn the ignition ON, but do not start the engine.
Is communication established between the scan tool
and the immobilizer control unit?
–
Go to Step 2
Go to
“Communi-
cation
Between
Immobilizer
and Test
Equipment”
2
Select CURRENT KEY STATUS from the scan tool
menu.
Did the STATUS OF CURRENT KEY message
indicate “KEY IS WRONG”?
–
Go to “Key
Status Errors”
Go to Step 3
3
Read the IMMO & ECM ID CODE message that
was displayed after requesting DIAGNOSIS.
Did the message differ from normal message?
Normal Message –ECM MODE: LEARNT
IMMO. MODE: LEARNT
VIN CODE: SAME
–
Go to
“Identification
(ID) Code
Repro-
gramming”
Go to Step 4
4
Check for an open serial data wire between the
immobilizer control unit and the ECM.
Was the circuit open?
–
Go to Step 5Go to Step 6
5
Repair the open serial data wire between the ECM
and the immobilizer control unit.
Is the repair complete?
–
System OK
–
6
1. Replace the ECM.
2. Reprogram the identification (ID) code. Refer to
“Identification (ID) Code Reprogramming” in this
section.
Is the repair complete?
–
System OK
–
Page 1173 of 1184

IMMOBILIZER ANTI-THEFT SYSTEM 9T–21
DAEWOO M–150 BL2
P 1628 – ECM Immobilizer Error (No Successful Communication)
StepActionValueYesNo
1
Connect the scan tool using the following procedure:
1. Insert the cartridge into the scan tool.
2. Turn the ignition switch to the OFF position.
3. Connect the scan tool to the data link connector
(DLC).
4. Connect the scan tool’s power cord to the cigar
lighter socket.
5. Select immobilizer mode on the scan tool.
6. Turn the ignition ON, but do not start the engine.
Is communication established between the scan tool
and the immobilizer control unit?
–
Go to Step 2
Go to
“Communi-
cation
Between
Immobilizer
and Test
Equipment”
2
Read the IMMO & ECM ID CODE message that
was displayed after requesting DIAGNOSIS.
Did the message differ from normal message?
Normal Message –ECM MODE: LEARNT
IMMO. MODE: LEARNT
VIN CODE: SAME
–
Go to
“Identification
(ID) Code
Repro-
gramming”
Go to Step 3
3
Check for an open serial data wire between the
immobilizer control unit and the ECM.
Was the circuit open?
–
Go to Step 4Go to Step 5
4
Repair the open serial data wire between the ECM
and the immobilizer control unit.
Is the repair complete?
–
System OK
–
5
1. Replace the immobilizer.
2. Reprogram the identification (ID) code. Refer to
“Identification (ID) Code Reprogramming” in this
section.
Is the repair complete?
–
System OK
–
Go to Step 6
6
1. Replace the ECM.
2. Turn the ignition ON, OFF for more than 4
seconds.
3. Turn the ignition ON.
Is the repair complete?
–
System OK
–
Page 1179 of 1184

IMMOBILIZER ANTI-THEFT SYSTEM 9T–27
DAEWOO M–150 BL2
6. Turn the ignition OFF and ON again, but do not
crank or start the engine. The ECM will reset the
ECM ID code to match the new ID code that was
calculated and sent by the immobilizer control unit
when the ignition was first turned ON after the reset
command.
7. Return the system to the normal mode.
8. Turn OFF the ignition.
9. Turn ON the ignition.
10. Start the engine.
After reprogramming the ID code, the scan tool SYS-
TEM DIAGNOSIS command can verify that the ECM ID
code matches the immobilizer control unit ID code.
If the reprogramming procedure does not result in
matching ID codes, check the electrical connectors for
the serial data wire between the immobilizer control unit
and the ECM.
TRANSPONDER
Each valid ignition key has an internal transponder
which is a read /write transponder.
The transponder contains an implementation of a cryp-
to-algorithm with 96 bits of user configurable secret-key
contained in EEPROM and transmits data to the ICU by
modulating the amplitude of the electromagnetic field,
and receives data and commands in a similar way.
D105A504
DETECTION COIL
(Left–Hand Drive Shown, Right–Hand
Drive Similar)
Removal Procedure
1. Remove the steering column covers. Refer to Section
6E, Steering Wheel and Column.
D29T001
2. Remove the detection coil.
Disconnect the two-pin connector from the detec-
tion coil (1).
Pry the detection coil away from the lock cylinder
(2).
Important: If the detection coil will be replaced with a
new one, it does not matter if the key position trim ring is
damaged during removal. A new trim ring is part of the
new detection coil.