2003 DAEWOO MATIZ Service Repair Manual

ENGINE CONTROLS 1F–231
DAEWOO M-150 BL2
a Freeze Frame conditions (rpm, load, vehicle speed, temperature, etc.) that .are noted. This will isolate when
the DTC failed.
DTC P0480 – Low Speed Cooling Fan Relay Circuit Fault (with A/C)
StepActionValue(s)YesNo
1
Perform an Euro 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 switch to ON with the engine
OFF.
2. Install a scan tool.
3. Command the relay ON and OFF.
Does the relay turn ON and OFF when
commanded?
–
Go to Step 3Go to Step 5
3
1. Turn the ignition switch to LOCK.
2. Disconnect the engine control module (ECM)
connector.
3. Turn the ignition switch to ON.
4. Using a digital voltmeter(DVM), measure the
current in low speed relay control circuit, at
terminal 10 to ground for 2 minutes.
Does the amperage measure less than the specified
value?
0.75 amps
Go to
“Diagnostic
Aids”
Go to Step 4
4
1. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Using a DVM, measure the resistance between
terminals 85 and 5 in the relay control circuit in
the ECM harness connector to ground.
Does the DVM display infinite resistance?
–
Go to Step 12Go to Step 10
5
1. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Connect a test light between the relay coil
terminals 86 and 85 in the relay harness
connector.
4. Turn the Turn the ignition switch to ON.
5. Using the scan tool, command the relay ON and
OFF.
Does the test light turn ON and OFF with each
commanded?
–
Go to Step 8Go to Step 6
6
With the test light connected to ground, probe the
ignition feed circuit in the relay harness connector.
Does the test light illuminate?
–
Go to Step 7Go to Step 11
7
1. Turn the ignition switch to LOCK.
2. Reconnect the relay.
3. Disconnect the ECM connector containing the
relay control circuit.
4. Turn the Turn the ignition switch to ON.
5. With a fused jumper wire connected to ground,
probe the relay control circuit at terminal 5 in the
ECM harness connector.
Does the relay operate?
–
Go to Step 9Go to Step 10
8Check the connections at the relay.
Is a problem found and corrected?–Go to Step 14Go to Step 12

1F–232 ENGINE CONTROLS
DAEWOO M-150 BL2
DTC P0480 – Low Speed Cooling Fan Relay Circuit Fault (with A/C) (Cont’d)
StepActionValue(s)YesNo
9Check the connection at the ECM.
Is a problem found and corrected?–Go to Step 11Go to Step 13
10Repair the faulty relay control circuit.
Is the repair complete?–Go to Step 14–
11Repair the faulty relay ignition feed circuit.
Is the repair complete?–Go to Step 14–
12Replace the relay.
Is the replacement complete?–Go to Step 14–
13Replace the ECM.
Is the replacement complete?–Go to Step 14–
14
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 the DTC as specifiec in the supporting
text.
Does the scan tool indicate that this diagnostic ran
and passed?
–
Go to Step 15Go to Step 2
15
Check if any additional DTCs are set.
Are any DTCs displayed that have not been
diagnosed?
–
Go to
Applicable DTC
table
System OK

ENGINE CONTROLS 1F–233
DAEWOO M-150 BL2
BLANK

1F–234 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F090
DIAGNOSTIC TROUBLE CODE (DTC) – P0481 HIGH SPEED COOLING FAN
RELAY CIRCUIT FAULT (WITHOUT A/C)
Circuit Description
Ignition voltage is supplied directly to the cooling fan
relay coil. The engine control module(ECM) controls the
relay by grounding the control circuit via an internal
switch called a driver. The primary function of the driver
is supply the ground for the component being controlled.
Each driver has a fault line which is monitored by the
ECM. When the ECM is commanding a component ON,
the voltage of the control circuit should be low (near
0volts). When the ECM is commanding the control cir-
cuit to a component OFF, the voltage potential of the cir-
cuit should be high(near battery voltage). If the fault
detection circuit senses a voltage other than what is ex-
pected, the fault line status will change causing the DTC
to set.
The relay is used to control the high current flow to the
cooling fan motors. This allows the ECM driver to only
have to handle the relatively low current used by the
relay.
Conditions for Setting the DTC

Diagnostic Trouble Codes (DTCs) P0117, P0118 not
set.

Ignition ON.
Ignition voltage is greater than 10 volts.

Engine run time is greater than 5 seconds.
Action Taken When The DTCs Sets

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

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

This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC

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

DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
Using Freeze Frame and/or failure records data may aid
in locating an intermittent condition. If the DTC cannot
be duplicated, the information included in the Freeze
Frame and/or failure records data can be useful in deter-
mining how many miles since the DTC set. The fail
counter and Pass Counter can also be used to deter-
mine how many ignition cycles the diagnostics reported

ENGINE CONTROLS 1F–235
DAEWOO M-150 BL2
a Freeze Frame conditions (rpm, load, vehicle speed, temperature, etc.) that .are noted. This will isolate when
the DTC failed.
DTC P0481 – High Speed Cooling Fan Relay Circuit Fault (without A/C)
StepActionValue(s)YesNo
1
Perform an Euro 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 switch to ON with the engine
OFF.
2. Install a scan tool.
3. Command the relay ON and OFF.
Does the relay turn ON and OFF when
commanded?
–
Go to Step 3Go to Step 5
3
1. Turn the ignition switch to LOCK.
2. Disconnect the engine control module (ECM)
connector.
3. Turn the ignition switch to ON.
4. Using a digital voltmeter(DVM), measure the
current in high speed relay control circuit, at
terminal 5 to ground for 2 minutes.
Does the amperage measure less than the specified
value?
0.75 amps
Go to
“Diagnostic
Aids”
Go to Step 4
4
1. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Using a DVM, measure the resistance between
terminals 85 and 5 in the relay control circuit in
the ECM harness connector to ground.
Does the DVM display infinite resistance?
–
Go to Step 12Go to Step 10
5
1. Turn the ignition switch to LOCK.
2. Disconnect the relay.
3. Connect a test light between the relay coil
terminals 86 and 85 in the relay harness
connector.
4. Turn the Turn the ignition switch to ON.
5. Using the scan tool, command the relay ON and
OFF.
Does the test light turn ON and OFF with each
commanded?
–
Go to Step 8Go to Step 6
6
With the test light connected to ground, probe the
ignition feed circuit in the relay harness connector.
Does the test light illuminate?
–
Go to Step 7Go to Step 11
7
1. Turn the ignition switch to LOCK.
2. Reconnect the relay.
3. Disconnect the ECM connector containing the
relay control circuit.
4. Turn the Turn the ignition switch to ON.
5. With a fused jumper wire connected to ground,
probe the relay control circuit at terminal 5 in the
ECM harness connector.
Does the relay operate?
–
Go to Step 9Go to Step 10
8Check the connections at the relay.
Is a problem found and corrected?–Go to Step 14Go to Step 12

1F–236 ENGINE CONTROLS
DAEWOO M-150 BL2
DTC P0481 – High Speed Cooling Fan Relay Circuit Fault (without A/C) (Cont’d)
StepActionValue(s)YesNo
9Check the connection at the ECM.
Is a problem found and corrected?–Go to Step 11Go to Step 13
10Repair the faulty relay control circuit.
Is the repair complete?–Go to Step 14–
11Repair the faulty relay ignition feed circuit.
Is the repair complete?–Go to Step 14–
12Replace the relay.
Is the replacement complete?–Go to Step 14–
13Replace the ECM.
Is the replacement complete?–Go to Step 14–
14
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 the DTC as specifiec in the supporting
text.
Does the scan tool indicate that this diagnostic ran
and passed?
–
Go to Step 15Go to Step 2
15
Check if any additional DTCs are set.
Are any DTCs displayed that have not been
diagnosed?
–
Go to
Applicable DTC
table
System OK

ENGINE CONTROLS 1F–237
DAEWOO M-150 BL2
BLANK

1F–238 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F270
DIAGNOSTIC TROUBLE CODE (DTC) – P0481 HIGH SPEED COOLING FAN
RELAY CIRCUIT FAULT (WITH A/C)
Circuit Description
Ignition voltage is supplied directly to the cooling fan
relay coil. The engine control module(ECM) controls the
relay by grounding the control circuit via an internal
switch called a driver. The primary function of the driver
is supply the ground for the component being controlled.
Each driver has a fault line which is monitored by the
ECM. When the ECM is commanding a component ON,
the voltage of the control circuit should be low (near
0volts). When the ECM is commanding the control cir-
cuit to a component OFF, the voltage potential of the cir-
cuit should be high(near battery voltage). If the fault
detection circuit senses a voltage other than what is ex-
pected, the fault line status will change causing the DTC
to set.
The relay is used to control the high current flow to the
cooling fan motors. This allows the ECM driver to only
have to handle the relatively low current used by the
relay.
Conditions for Setting the DTC

Diagnostic Trouble Codes (DTCs) P0117, P0118 not
set.

Ignition ON.
Ignition voltage is greater than 10 volts.

Engine run time is greater than 5 seconds.
Action Taken When The DTCs Sets

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

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

This information will not be stored in the Freeze
Frame data.
Conditions for Clearing the MIL/DTC

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

DTC(s) can be cleared by using the scan tool.
Diagnostic Aids
Using Freeze Frame and/or failure records data may aid
in locating an intermittent condition. If the DTC cannot
be duplicated, the information included in the Freeze
Frame and/or failure records data can be useful in deter-
mining how many miles since the DTC set. The fail
counter and Pass Counter can also be used to deter-
mine how many ignition cycles the diagnostics reported