Daewoo Matiz (2003 year). Manual — part 90

1F – 270 ENGINE CONTROLS

MAA1F330

DIAGNOSTIC TROUBLE CODE (DTC) – P1628 IMMOBILIZER NO SUCCESSFUL

COMMUNICATION

Circuit Description

When the ignition switch is turned to ON, the key tested
by immobilizer anti-theft system. While the key code is
being read by immobilizer control unit or integrated anti-
theft control unit, the engine can start run with any key
that will turn the lock cylinder. the key code is read and
compared with key codes that have been stored in the
memory of the immobilizer control unit. If a valid key is
detected, the immobilizer control unit sends a serial data
release message to the Engine Control Module (ECM).
Included in the release message is an identification (ID)
code which assures that neither the immobilizer control
unit nor the ECM have been substituted to defeat the
system. If the ECM receives an invalid release mes-
sage, the ECM performs the following action:

D

Disable the fuel injector circuit.

D

Disable the fuel pump circuit.

D

Disable the ignition coil.

D

A Diagnostic Trouble Code (DTC) will stored if detect
communication link failure between the ECM and im-
mobilizer control unit.

Conditions for Setting the DTC

D

Ignition switch is turned to ON.

D

Immobilizer option auto detected.

D

ECM release time window(1.5 or 2 seconds) expired.

D

Vehicle Speed Sensor (VSS) signal is less than 512
km/h.

Action Taken When the DTC Sets

D

The Malfunction Indicator Lamp (MIL) will not illumi-
nate.

D

The ECM will store conditions which were present
when the DTC was set as Failure Records data only.

D

This information will not be stored in the Freeze
Frame data.

Conditions for Clearing the MIL/DTC

D

A history DTC will clear after 40 consecutive warm-up
cycles without a fault.

D

DTC(s) can be cleared by using the scan tool.

ENGINE CONTROLS 1F – 271

DTC P1628 – Immobilizer No Successful Communication

Step

Action

Value(s)

Yes

No

1

Perform an On-Board Diagnostic (EOBD) System
Check.
Is the system check complete?

–

Go to Step 2

Go to

“On-Board
Diagnostic

System Check”

2

1. Turn the ignition OFF.
2. Install a scan too to the Data Link Connector

(DLC).

3. Turn the ignition ON.
4. Select IMMOBILIZER DIAGNOSIS STATUS from

the scan tool menu.

Is the communication established between the scan
tool and the immobilizer control unit?

–

Go to Step 3

Go to Section

9T, Immobilizer

Anti-Theft

System

3

1. Turn the ignition OFF.
2. Disconnect the Immobilizer Control Unit and

Engine Control Module (ECM) connectors.

3. Measure the resistance between terminal 7 of

immoblizer control unit and terminal 56 of the
ECM.

Is the resistance within the specified value?

0

Ω

Go to Step 5

Go to Step 4

4

Repair an open circuit between terminal 7 of
immobilizer control unit and terminal 56 of the ECM.
Is the repair complete?

–

Go to Step 8

–

5

Check the terminals in immobilizer control unit and
the ECM for damages and repair as needed.
Is the repair complete?

–

Go to Step 8

Go to Step 6

6

Replace the immobilizer control unit.
Is the repair complete?

–

Go to Step 8

Go to Step 7

7

1. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?

–

Go to Step 8

–

8

1. Using the scan tool, clear the Diagnostic Trouble

Codes (DTCs).

2. Start the engine and idle at normal operating

temperature.

3. Operate the vehicle within the Conditions for

setting this DTC as specified in the supporting
text.

Does the scan tool indicate that this diagnostic has
run and passed?

–

Go to Step 9

Go to Step 2

9

Check if any additional DTCs are set.
Are any DTCs displayed that have not been
diagnosed?

–

Go to

Applicable DTC

Table

System OK

1F – 272 ENGINE CONTROLS

MAA1F330

DIAGNOSTIC TROUBLE CODE (DTC) – P1629 IMMOBILIZER WRONG

COMPUTATION

Circuit Description

When the ignition switch is turned to ON, the key tested
by immobilizer anti-theft system. While the key code is
being read by immobilizer control unit or integrated anti-
theft control unit, the engine can start run with any key
that will turn the lock cylinder. the key code is read and
compared with key codes that have been stored in the
memory of the immobilizer control unit. If a valid key is
detected, the immobilizer control unit sends a serial data
release message to the Engine Control Module (ECM).
Included in the release message is an identification (ID)
code which assures that neither the immobilizer control
unit nor the ECM have been substituted to defeat the
system. If the ECM receives an invalid release mes-
sage, the ECM performs the following action:

D

Disable the fuel injector circuit.

D

Disable the fuel pump circuit.

D

Disable the ignition coil.

A Diagnostic Trouble Code (DTC) will stored if detect
communication link failure between the ECM and immo-
bilizer control unit.

Conditions for Setting the DTC

D

Ignition switch is turned to ON.

D

Immobilizer option auto detected.

D

ECM release time window(1.5 or 2 seconds) expired.

D

Vehicle Speed Sensor (VSS) signal is less than 512
km/h.

Action Taken When the DTC Sets

D

The Malfunction Indicator Lamp (MIL) will not illumi-
nate.

D

The ECM will store conditions which were present
when the DTC was set as Failure Records data only.

D

This information will not be stored in the Freeze
Frame data.

Conditions for Clearing the MIL/DTC

D

A history DTC will clear after 40 consecutive warm-up
cycles without a fault.

D

DTC(s) can be cleared by using the scan tool.

ENGINE CONTROLS 1F – 273

DTC P1629 – Immobilizer Wrong Computation

Step

Action

Value(s)

Yes

No

1

Perform an On-Board Diagnostic (EOBD) System
Check.
Is the system check complete?

–

Go to Step 2

Go to

“On-Board
Diagnostic

System Check”

2

1. Turn the ignition OFF.
2. Install a scan too to the Data Link Connector

(DLC).

3. Turn the ignition ON.
4. Select IMMOBILIZER DIAGNOSIS STATUS from

the scan tool menu.

Is the communication established between the scan
tool and the immobilizer control unit?

–

Go to Step 3

Go to Section

9T, Immobilizer

Anti-Theft

System

3

1. Turn the ignition OFF.
2. Disconnect the Immobilizer Control Unit and

Engine Control Module (ECM) connectors.

3. Measure the resistance between terminal 7 of

immoblizer control unit and terminal 56 of the
ECM.

Is the resistance within the specified value?

0

Ω

Go to Step 5

Go to Step 4

4

Repair an open circuit between terminal 7 of
immobilizer control unit and terminal 56 of the ECM.
Is the repair complete?

–

Go to Step 8

–

5

Check the terminals in immobilizer control unit and
the ECM for damages and repair as needed.
Is the repair complete?

–

Go to Step 8

Go to Step 6

6

Replace the immobilizer control unit.
Is the repair complete?

–

Go to Step 8

Go to Step 7

7

1. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?

–

Go to Step 8

–

8

1. Using the scan tool, clear the Diagnostic Trouble

Codes (DTCs).

2. Start the engine and idle at normal operating

temperature.

3. Operate the vehicle within the Conditions for

setting this DTC as specified in the supporting
text.

Does the scan tool indicate that this diagnostic has
run and passed?

–

Go to Step 9

Go to Step 2

9

Check if any additional DTCs are set.
Are any DTCs displayed that have not been
diagnosed?

–

Go to

Applicable DTC

Table

System OK