DAEWOO MATIZ 2003 Service Repair Manual

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

ENGINE CONTROLS 1F–239
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 (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 high speed relay control circuit, at
terminal 39 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 39 in the high speed cooling fan
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 10 in the
ECM harness connector.
Does the relay operate?
–
Go to Step 9Go to Step 10

1F–240 ENGINE CONTROLS
DAEWOO M-150 BL2
DTC P0481 – High Speed Cooling Fan Relay Circuit Fault (with A/C) (Cont’d)
StepActionValue(s)YesNo
8Check the connections at the relay.
Is a problem found and corrected?–Go to Step 14Go to Step 12
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–241
DAEWOO M-150 BL2
BLANK

1F–242 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F280
DIAGNOSTIC TROUBLE CODE (DTC) – P0501 VEHICLE SPEED NO SIGNAL
(M/T ONLY)
Circuit Description
Vehicle speed information is provided to the engine con-
trol module (ECM) by the voltage speed sensor (VSS) is
a permanent magnet generator that is mounted in the
transaxle and produces a pulsing voltage whenever ve-
hicle speed is over 3 mph (5km/h). The A/C voltage level
and the number of pulses increase with vehicle speed.
The ECM converts the pulsing voltage into mph (km/h)
and than supplies the necessary signal to the instrument
panel for speedometer / odometer operation and to the
cruise control module and multi-function alarm module
operation. The Diagnostic Trouble Code (DTC) will de-
tect if vehicle speed is reasonable according to engine
rpm and load.
Conditions for Setting the DTC

Vehicle speed is not change at least 10 seconds.

Engine speed is greater than 2,100rpm.

MAF is greater than 152mg/tdc.
Action taken when The DTCs Sets

The Malfunction Indicator Lamp (MIL) will illuminate.

The ECM will record operating conditions at the time
the diagnostic fails. This information will be stored in
the Freeze Frame and failure records buffers.

A history DTC is stored.Conditions for Clearing the MIL/DTC

The MIL will turn off after four consecutive ignition
cycles in which the diagnostic runs without a fault.

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

Using the scan tool can clear DTC(s).
Diagnostic Aids
An Intermittent problem may be caused by a poor con-
nection, rubbed through wire insulation, or wire that is
broken inside the insulation.
VSS signal circuit should be thoroughly checked for the
following conditions

Backed-out terminals

Improper mating

Broken locks

Improperly formed

Damaged terminals

Poor terminals to wire connection

Physical damage to the wiring harness
Ensure the VSS is correctly torqued to the trnasaxle
housing.
Refer to “intermittents” in this Section.