Daewoo Matiz (2003 year). Manual - part 35

1F – 50  ENGINE CONTROLS

Engine Cooling Fan Circuit Check (Cont’d)

Step

Action

Value(s)

Yes

No

12

1. Turn the ignition ON.
2. Connect a test light between terminals 86 and 30

of low speed cooling fan relay and ground.

Does the test light on for both case?

–

Go to Step 14

Go to Step 13

13

Repair power supply circuit.

D

Fuse EF15 and terminal 30 of low speed cooling
fan relay.

Is the repair complete?

–

System OK

Go to Step 14

14

1. Turn the ignition OFF.
2. Disconnect Engine Control Module (ECM)

connectors.

3. Turn the ignition ON.
4. Connect a jump wire between terminal 5 and

ground.

Does the cooling fan run at low speed?

–

Go to Step 15

Go to Step 16

15

Replace the ECM.
Is the repair complete?

–

System OK

–

16

1. Turn the ignition OFF.
2. Measure the resistance between following

terminals:

D

Terminal 85 of low speed cooling fan relay and
terminal 39 of ECM connector.

Are the resistance within the value specified?

0 

Ω

Go to Step 18

Go to Step 17

17

Repair open circuit.
Is the repair complete?

–

System OK

–

18

Replace the low speed cooling fan relay.
Is the repair complete?

–

System OK

–

ENGINE CONTROLS  1F – 51

BLANK

1F – 52  ENGINE CONTROLS

MAA1F010

DATA LINK CONNECTOR DIAGNOSIS

Circuit Description

The provision for communicating with the Engine Con-
trol Module (ECM) is the Data Link Connector (DLC). It
is located under the instrument panel. The DLC is used
to connect the scan tool. Battery power and ground is
supplied for the scan tool through the DLC. The Key-
word 2000 serial data circuit to the DLC allows the ECM
to communicate with the scan tool. A Universal Asyn-
chronous Receiver Transmitter (UART) serial data line
is used to communicate with the other modules such as
the Electronic Brake Control Module (EBCM), the Sup-
plemental Inflatable Restraint (SIR) system. and the In-
strument Panel Cluster.

Diagnostic Aids

Ensure that the correct application (model line, car year,
etc.) has been selected on the scan tool. If communica-
tion still cannot be established, try the scan tool on

another vehicle to ensure that the scan tool or cables
are not the cause of the condition.

An intermittent may be caused by a poor connection,
rubbed through wire insulation, or a broken wire inside
the insulation.

Any circuitry that is suspected of causing an intermittent
complaint should be thoroughly checked for the follow-
ing conditions:

D

Backed-out terminals.

D

Improper mating of terminals.

D

Broken locks.

D

Improperly formed or damaged terminals.

D

Poor terminal-to-wiring connection.

D

Physical damage to the wiring harness.

D

Corrosion.

ENGINE CONTROLS  1F – 53

Data Link Connector Diagnosis

Step

Action

Value(s)

Yes

No

1

Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Was the check performed?

–

Go to Step 2

Go to “Euro

On-Board

Diagnostic

System Check.

2

With a test light connected to the ground, probe the
Data Link Connector (DLC) battery feed terminal 16.
Is the test light on?

–

Go to Step 4

Go to Step 3

3

Repair an open or short to ground in the DLC battery
feed circuit .
Is the repair complete?

–

Go to Step 4

–

4

With a test light connected to the battery, probe the
Data Link Connector (DLC) ground terminal 4 and 5.
Is the test light on?

–

Go to Step 6

Go to Step 5

5

Repair an open circuit .
Is the repair complete?

–

Go to Step 6

–

6

1. Turn the ignition OFF.
2. Connect a scan tool to the Data Link Connector

(DLC).

3. Turn the ignition ON.
Does the scan tool power up?

–

Go to Step 8

Go to Step 7

7

Check for damages in the terminal of DLC and scan
tool, and repair as needed.
Is the repair complete?

–

Go to Step 8

–

8

Using a scan tool, request engine data of Engine
Control Module (ECM).
Does the scan tool display any data?

–

Go to Step 12

Go to Step 9

9

Install the scan tool on another vehicle and check for
proper operation.
Does the scan tool work properly on a different
vehicle.

–

Go to Step 11

Go to Step 10

10

The scan tool is malfunctioning.
Refer to the scan tool’s manual for repair.
Is the repair complete?

–

Go to Step 12

–

11

Repair communication circuit between ECM and
DLC.
Is the repair complete?

–

Go to Step 12

–

12

1. Using a scan tool, clear the Diagnostic Trouble

Codes(DTCs).

2. Attempt to start the engine.
Does the engine and continue to run?

–

Go to Step 13

Go to Step 1

13

1. Allow the engine to idle until normal operation

temperature reached.

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

–

Go to applicable

DTC table

System OK