Page 345 of 1184

ENGINE CONTROLS 1F–247
DAEWOO M-150 BL2
Excessive engine overloading. Check for seized pul-
leys, pumps, or motors on the accessory drive,Overweight engine oil.
DTC P0505 Idle Air Control Valve (IACV) Circuit Fault
StepActionValue(s)YesNo
1
Perform an On-Board Diagnostic (EOBD) System
Check.
Was the check performed?
–
Go to Step 2
Go to
“On-Board
Diagnostic
System Check”
2
1. Install a scan tool to the Data Link Connector
(DLC).
2. Operate the engine to idle speed.
3. Transmission in park or neutral and the parking
brake set.
4. A/C is off.
5. Using scan tool, command the Idle Air Control
(IAC) valve up and down between the specified
value.
Does the rpm change smoothly when he
commanded by the scan tool?
900–1200
rpm
Go to Step 3Go to Step 5
3
1. Turn the ignition OFF.
2. Disconnect the IAC valve connector.
3. Measure the resistance between terminal C and
D of the IAC valve.
4. Measure the resistance between terminal B and A
of the IAC valve.
Is the resistance within the specified value?
40–80 ΩGo to Step 4Go to Step 13
4
1. Measure the resistance between terminal D and
B of the IAC valve.
2. Measure the resistance between terminal C and
A of the IAC valve.
Is the resistance equal to the specified value?
∞Go to Step 15Go to Step 13
5
1. Turn the ignition OFF.
2. Disconnect the IAC valve connector.
3. Turn the ignition ON.
4. With test light connected to ground, probe the
IAC connector terminals.
Does the test light illuminate on D terminals?
–
Go to Step 6Go to Step 7
6
With test light connected to B+, probe the IAC
connector terminals.
Does the test light illuminate on D terminals?
–
Go to Step 8Go to Step 9
7
Check for an open or short to ground in the IAC high
and low circuits and repair as needed.
Is the repair complete?
–
Go to Step 15Go to Step 10
8
1. Idle the engine.
2. Connect a test light to ground, probe the IAC
connector terminals.
Does the test light flash On and OFF for all
terminals?
–
Go to Step 11Go to Step 12
9
Check for an open or a short to voltage in the IAC
valve high and low circuits and repair as needed.
Is the repair complete?
–
Go to Step 15Go to Step 10
10
Check the Engine control Module (ECM) connector
for poor connections and repair as needed.
Is the repair complete?
–
Go to Step 15Go to Step 14
Page 346 of 1184

1F–248 ENGINE CONTROLS
DAEWOO M-150 BL2
DTC P0505 Idle Air Control Valve (IACV) Circuit Fault (Cont’d)
StepActionValue(s)YesNo
11
Inspect the IAC valve passages and repair as
needed.
Is the repair complete?
–
Go to Step 15Go to Step 13
12
Check the test light.
Does the test light remain on constantly for the
terminals that did not blink?
–
Go to Step 9Go to Step 7
13
1. Turn the ignition OFF.
2. Replace the IAC valve.
Is the repair complete?
–
Go to Step 15
–
14
1. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?
–
Go to Step 15
–
15
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 16Go to Step 2
16
Check if any additional DTCs are set.
Are any DTCs displayed that have not been
diagnosed?
–
Go to
Applicable DTC
Table
System OK
Page 347 of 1184
ENGINE CONTROLS 1F–249
DAEWOO M-150 BL2
BLANK
Page 348 of 1184

1F–250 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F300
DIAGNOSTIC TROUBLE CODE (DTC) – P1535 EVAPORATOR TEMPERATURE
SENSOR HIGH VOLTAGE
Circuit Description
A semiconductor which resistance is noticeably
changed as the change of temperature. When the refrig-
erant temperature of the evaporator drops to 0°C (0°F)
and below, the evaporator cores get stuck with frost or
ice, reducing the airflow, lowering the cooling capacity.
The thermistor is a sensor which is used to prevent from
frosting or icing. The thermistor is installed on the evap-
orator.
Conditions for Setting the DTC
A short to battery voltage condition exists and is pres-
ent for more the 2 seconds.
Action Taken When the DTC Sets
The ECM will not illuminate the Malfunction Indicator
Lamp (MIL).A history DTCs is stored.
The ECM will record operating conditions at the time
the diagnostic fails. This information will be stored
Failure Records buffers.
The A/C compressor operation will be disabled while
the low voltage indication exists.
Update the fail record each time the diagnostic test
fail.
Conditions for Clearing the MIL/DTC
A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
Usisng the scan tool can clear DTC(s).
Disconnecting the ECM battery feed for 10 seconds.
Page 349 of 1184

ENGINE CONTROLS 1F–251
DAEWOO M-150 BL2
DTC P1535 – Evaporator Temperature Sensor High Voltage
StepActionValue(s)YesNo
1
Perform an On-Board Diagnostic (EOBD II) 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 LOCK.
2. Disconnect the evaporator temperature sensor.
3. Measure the resistance between evaporator
temperature sensor terminals 1 and 2.
Does the resistance within the specified value?
0ΩGo to Step 7Go to Step 3
3
1. Turn the ignition switch to LOCK.
2. With the test light, connected to ground, probe
the ignition feed circuit, at terminal 2 in the sensor
harness connector.
Does the test light illuminate?
–
Go to Step 4Go to Step 5
4
Repair a short to battery between the terminal 46 of
ECM and A/C compressor relay terminal 2.
Is the repair complete?
–
Go to Step 9
–
5
1. Turn the ignition switch to LOCK.
2. Disconnect the ECM.
3. With the test light, connected to ground, probe
the ignition feed circuit, at terminal 2 in the sensor
harness connector.
Does the test light illuminate?
–
Go to Step 6Go to Step 8
6
Repair a short to battery between the ECM wiring
connector terminal 46 and evaporator temperature
sensor terminal 2.
Is the repair complete?
–
Go to Step 9
–
7Replace the evaporator temperature sensor.
Is the replacement complete?–Go to Step 9–
8
1. Turn the ignition switch to LOCK.
2. Replace the ECM.
Is the repair complete?
–
Go to Step 9
–
9
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 10Go to Step 2
10
Check if any additional DTCs are set.
Are any DTCs displayed that that have not been
diagnosed?
–
Go to
applicable DTC
table
System OK
Page 350 of 1184

1F–252 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F300
DIAGNOSTIC TROUBLE CODE (DTC) – P1536 EVAPORATOR TEMPERATURE
SENSOR LOW VOLTAGE
Circuit Description
A semiconductor which resistance is noticeably
changed as the change of temperature. When the refrig-
erant temperature of the evaporator drops to 0°C (0°F)
and below, the evaporator cores get stuck with frost or
ice, reducing the airflow, lowering the cooling capacity.
The thermistor is a sensor which is used to prevent from
frosting or icing. The thermistor is installed on the evap-
orator.
Conditions for Setting the DTC
A short to battery voltage condition exists and is pres-
ent for more the 2 seconds.
Action Taken When the DTC Sets
The ECM will not illuminate the Malfunction Indicator
Lamp (MIL).A history DTCs is stored.
The ECM will record operating conditions at the time
the diagnostic fails. This information will be stored
Failure Records buffers.
The A/C compressor operation will be disabled while
the low voltage indication exists.
Update the fail record each time the diagnostic test
fail.
Conditions for Clearing the MIL/DTC
A history DTC will clear after 40 consecutive warm-up
cycles without a fault.
Usisng the scan tool can clear DTC(s).
Disconnecting the ECM battery feed for 10 seconds.
Page 351 of 1184

ENGINE CONTROLS 1F–253
DAEWOO M-150 BL2
DTC P1536 – Evaporator Temperature Sensor Low Voltage
StepActionValue(s)YesNo
1
Perform an On-Board Diagnostic (EOBD II) System
Check.
Is the system check complete?
–
Go to Step 2
Go to
“On-Board
Diagnostic
System Check”
2
2.. Turn the ignition switch to LOCK.
2. Disconnect the evaporator temperature sensor.
3. Measure the resistance between evaporator
temperature sensor terminals 1 and 2.
Does the resistance within the specified value?
0ΩGo to Step 7Go to Step 3
3
1. Turn the ignition switch to LOCK.
2. With the test light, connected to ground, probe
the ignition feed circuit, at terminal 2 in the sensor
harness connector.
Does the test light illuminate?
–
Go to Step 4Go to Step 5
4
Repair a short to battery between the terminal 46 of
ECM and A/C compressor relay terminal 2.
Is the repair complete?
–
Go to Step 9
–
5
1. Turn the ignition switch to LOCK.
2. Disconnect the ECM.
3. With the test light, connected to ground, probe
the ignition feed circuit, at terminal 2 in the sensor
harness connector.
Does the test light illuminate?
–
Go to Step 6Go to Step 8
6
Repair a short to battery between the ECM wiring
connector terminal 46 and evaporator temperature
sensor terminal 2.
Is the repair complete?
–
Go to Step 9
–
7Replace the evaporator temperature sensor.
Is the replacement complete?–Go to Step 9–
8
1. Turn the ignition switch to LOCK.
2. Replace the ECM.
Is the repair complete?
–
Go to Step 9
–
9
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 10Go to Step 2
10
Check if any additional DTCs are set.
Are any DTCs displayed that that have not been
diagnosed?
–
Go to
applicable DTC
table
System OK
Page 352 of 1184

1F–254 ENGINE CONTROLS
DAEWOO M-150 BL2
MAA1F310
DIAGNOSTIC TROUBLE CODE (DTC) – P1537 A/C COMPRESSOR RELAY HIGH
V O LTA G E
Circuit Description
The A/C system uses an A/C refrigerant pressure sen-
sor mounted in the high pressure side of the A/C refrig-
erant system to monitor A/C refrigerant pressure. The
engine control module (ECM) uses this information to
turn ON the engine coolant fans when the A/C refriger-
ant pressure is high and to keep the compressor disen-
gaged when A/C refrigerant pressure is excessively high
or low.
Conditions for Setting the DTC
A/C compressor relay circuit short to battery.
Action Taken When the DTC 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
Inspect harness connectors for backed-out terminals,
improper mating, broken locks, improperly formed or
damaged terminals, and poor terminal-to-wire connec-
tion at the ECM.
Inspect the wiring harness for damage. If the harness
appears to be OK, observe the A/C pressure display on
the scan tool while moving the connectors and wiring
harnesses related to the ACP sensor. A change in the
A/C pressure display will indicate the location of the
fault.
If DTC P1537 cannot be duplicated, reviewing the Fail
Records vehicle mileage since the diagnostic test last
failed may help determine how often the condition that
caused the DTC to set occurs. This may assist in diag-
nosing the condition.