engine electrical DAEWOO LACETTI 2004 Service Workshop Manual

1E – 30IENGINE ELECTRICAL
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
BATTERY
The sealed battery is standard on all cars. There are no
vent plugs in the cover. The battery is completely sealed,
except for two small vent holes in the sides. These vent
holes allow the small amount of gas produced in the bat-
tery to escape. The battery has the following advantages
over conventional batteries:
S No water addition for the life of the battery.
S Overcharge protection. If too much voltage is ap-
plied to the battery, it will not accept as much cur-
rent as a conventional battery. In a conventional
battery, the excess voltage will still try to charge the
battery, leading to gassing, which causes liquid
loss.
S Not as liable to self–discharge as compared to a
conventional battery. This is particularly important
when a battery is left standing for long periods of
time.
S More power available in a lighter and smaller case.
The battery has three major functions in the electrical sys-
tem. First, the battery provides a source of energy for
cranking the engine. Second, the battery acts as a voltage
stabilizer for the electrical system. Finally, the battery can,
for a limited time, provide energy when the electrical de-
mand exceeds the output of the generator.
RATINGS
A battery has two ratings: (1) a reserve capacity rating
designated at 27°C (80°F), which is the time a fully
charged battery will provide 25 amperes current flow at or
above 10.5 volts; (2) a cold cranking amp rating deter-
mined under testing at –18°C (0°F), which indicates the
cranking load capacity.
RESERVE CAPACITY
The reserve capacity is the maximum length of time it is
possible to travel at night with the minimum electrical load
and no generator output. Expressed in minutes, Reserve
Capacity (or RC rating) is the time required for a fully
charged battery, at a temperature of 27°C (80°F) and be-
ing discharged at a current of 25 amperes, to reach a ter-
minal voltage of 10.5 volts.
COLD CRANKING AMPERAGE
The cold cranking amperage test is expressed at a battery
temperature of –18°C (0°F). The current rating is the mini-
mum amperage, which must be maintained by the battery
for 30 seconds at the specified temperature, while meeting
a minimum voltage requirement of 7.2 volts. This rating is
a measure of cold cranking capacity.The battery is not designed to last indefinitely. However,
with proper care, the battery will provide many years of
service.
If the battery tests well, but fails to perform satisfactorily
in service for no apparent reason, the following factors
may point to the cause of the trouble:
S Vehicle accessories are left on overnight.
S Slow average driving speeds are used for short pe-
riods.
S The vehicle’s electrical load is more than the gener-
ator output, particularly with the addition of after-
market equipment.
S Defects in the charging system, such as electrical
shorts, a slipping generator belt, a faulty generator,
or a faulty voltage regulator.
S Battery abuse, including failure to keep the battery
cable terminals clean and tight, or a loose battery
hold–down clamp.
S Mechanical problems in the electrical system, such
as shorted or pinched wires.
BUILT – IN HYDROMETER
The sealed battery has a built–in, temperature–compen-
sated hydrometer in the top of the battery. This hydrome-
ter is to be used with the following diagnostic procedure:
1. When observing the hydrometer, make sure that
the battery has a clean top.
2. Under normal operation, two indications can be ob-
served:
S GREEN DOT VISIBLE – Any green appearance
is interpreted as a ”green dot,” meaning the bat-
tery is ready for testing.
S DARK GREEN DOT IS NOT VISIBLE – If there
is a cranking complaint, the battery should be
tested. The charging and electrical systems
should also be checked at this time.
3. Occasionally, a third condition may appear:
S CLEAR OR BRIGHT YELLOW – This means
the fluid level is below the bottom of the hydrom-
eter. This may have been caused by excessive
or prolonged charging, a broken case, excessive
tipping, or normal battery wear. Finding a battery
in this condition may indicate high charging by a
faulty charging system. Therefore, the charging
and the electrical systems may need to be
checked if a cranking complaint exists. If the
cranking complaint is caused by the battery, re-
place the battery.
CHARGING PROCEDURE
1. Batteries with the green dot showing do not require
charging unless they have just been discharged
(such as in cranking a vehicle).
2. When charging sealed–terminal batteries out of the
vehicle, install the adapter kit. Make sure all the
charger connections are clean and tight. For best
results, batteries should be charged while the elec-

ENGINE ELECTRICAL 1E – 31
DAEWOO V–121 BL4
trolyte and the plates are at room temperature. A
battery that is extremely cold may not accept cur-
rent for several hours after starting the charger.
3. Charge the battery until the green dot appears. The
battery should be checked every half–hour while
charging. Tipping or shaking the battery may be
necessary to make the green dot appear.
4. After charging, the battery should be load tested.
Refer to ”Starter Motor” in this section.
CHARGING TIME REQUIRED
The time required to charge a battery will vary depending
upon the following factors:
S Size of Battery – A completely discharged large
heavy–duty battery requires more than twice the re-
charging time as a completely discharged small pas-
senger car battery.
S Temperature – A longer time will be needed to
charge any battery at –18°C (0°F) than at 27°C
(80°F). When a fast charger is connected to a cold
battery, the current accepted by the battery will be
very low at first. The battery will accept a higher cur-
rent rate as the battery warms.
S Charger Capacity – A charger which can supply only
5 amperes will require a much longer charging period
than a charger that can supply 30 amperes or more.
S State–of–Charge – A completely discharged battery
requires more than twice as much charge as a one–
half charged battery. Because the electrolyte is nearly
pure water and a poor conductor in a completely dis-
charged battery, the current accepted by the battery
is very low at first. Later, as the charging current
causes the electrolyte acid content to increase, the
charging current will likewise increase.
CHARGING A COMPLETELY
DISCHARGED BATTERY (OFF THE
VEHICLE)
Unless this procedure is properly followed, a perfectly
good battery may need to be replaced.
The following procedure should be used to recharge a
completely discharged battery:
1. Measure the voltage at the battery terminals with
an accurate voltmeter. If the reading is below 10
volts, the charge current will be very low, and it
could take some time before the battery accepts
the current in excess of a few milliamperes. Refer
to ””Charging Time Required” in this section, which
focuses on the factors affecting both the charging
time required and the rough estimates in the table
below. Such low current may not be detectable on
ammeters available in the field.
2. Set the battery charger on the high setting.Important : Some chargers feature polarity protection cir-
cuitry, which prevents charging unless the charger leads
are correctly connected to the battery terminals. A com-
pletely discharged battery may not have enough voltage
to activate this circuitry, even though the leads are con-
nected properly, making it appear that the battery will not
accept charging current. Therefore, follow the specific
charger manufacturer’s instruction for bypassing or over-
riding the circuitry so that the charger will turn on and
charge a low–voltage battery.
3. Continue to charge the battery until the charge cur-
rent is measurable. Battery chargers vary in the
amount of voltage and current provided. The time
required for the battery to accept a measurable
charge current at various voltages may be as fol-
lows:
Voltage
Hours
16.0 or moreUp to 4 hours
14.0–15.9Up to 8 hours
13.9 or lessUp to 16 hours
S If the charge current is not measurable at the
end of the above charging times, the battery
should be replaced.
S If the charge current is measurable during the
charging time, the battery is good, and charging
should be completed in the normal manner.
Important : It is important to remember that a completely
discharged battery must be recharged for a sufficient num-
ber of ampere hours (AH) to restore the battery to a usable
state. As a general rule, using the reserve capacity rating
(RC) as the number of ampere hours of charge usually
brings the green dot into view.
S If the charge current is still not measurable after
using the charging time calculated by the above
method, the battery should be replaced.
JUMP STARTING PROCEDURE
1. Position the vehicle with the good (charged) battery
so that the jumper cables will reach.
2. Turn off the ignition, all the lights, and all the electri-
cal loads in both vehicles. Leave the hazard flasher
on if jump starting where there may be other traffic
and any other lights needed for the work area.
3. In both vehicles, apply the parking brake firmly.
Notice : To avoid vehicle damage,Make sure the cables
are not on or near pulleys, fans, or other parts that will
move when the engine starts.
4. Shift an automatic transaxle to PARK, or a manual
transaxle to NEUTRAL.
CAUTION : In order to avoid injury, do not use cables
that have loose or missing insulation.
5. Clamp one end of the first jumper cable to the posi-
tive terminal on the battery. Make sure it does not
touch any other metal parts. Clamp the other end of

1E – 32IENGINE ELECTRICAL
DAEWOO V–121 BL4
the same cable to the positive terminal on the other
battery. Never connect the other end to the nega-
tive terminal of the discharged battery.
CAUTION : To avoid injury do not attach the cable di-
rectly to the negative terminal of the discharged bat-
tery. Doing so could cause sparks and a possible bat-
tery explosion.
6. Clamp one end of the second cable to the negative
terminal of the booster battery. Make the final con-
nection to a solid engine ground (such as the en-
gine lift bracket) at least 450 millimeters (18 inches)
from the discharged battery.
7. Start the engine of the vehicle with the good bat-
tery. Run the engine at a moderate speed for sever-
al minutes. Then start the engine of the vehicle
which has the discharged battery.
8. Remove the jumper cables by reversing the above
sequence exactly. Remove the negative cable from
the vehicle with the discharged battery first. While
removing each clamp, take care that it does not
touch any other metal while the other end remains
attached.
GENERATOR
The Delco–Remy CS charging system has several mod-
els available, including the CS. The number denotes the
outer diameter in millimeters of the stator lamination.
CS generators are equipped with internal regulators. A
Delta stator, a rectifier bridge, and a rotor with slip rings
and brushes are electrically similar to earlier generators.
A conventional pulley and fan are used. There is no test
hole.
Unlike three–wire generators, the CS may be used with
only two connections: battery positive and an ”L’’ terminal
to the charge indicator lamp.
As with other charging systems, the charge indicator lamp
lights when the ignition switch is turned to RUN, and goes
out when the engine is running. If the charge indicator is
on with the engine running, a charging system defect is in-
dicated. This indicator light will glow at full brilliance for
several kinds of defects as well as when the system volt-
age is too high or too low.The regulator voltage setting varies with temperature and
limits the system voltage by controlling rotor field current.
At high speeds, the on–time may be 10 percent and the
off–time 90 percent. At low speeds, with high electrical
loads, on–time may be 90 percent and the off–time 10 per-
cent.
CHARGING SYSTEM
CS generators use a new type of regulator that incorpo-
rates a diode trio. A Delta stator, a rectifier bridge, and a
rotor with slip rings and brushes are electrically similar to
earlier generators. A conventional pulley and fan are used.
There is no test hole.
STARTER
Wound field starter motors have pole pieces, arranged
around the armature, which are energized by wound field
coils.
Enclosed shift lever cranking motors have the shift lever
mechanism and the solenoid plunger enclosed in the drive
housing, protecting them from exposure to dirt, icy condi-
tions, and splashes.
In the basic circuit, solenoid windings are energized when
the switch is closed. The resulting plunger and shift lever
movement causes the pinion to engage the engine fly-
wheel ring gear. The solenoid main contacts close. Crank-
ing then takes place.
When the engine starts, pinion overrun protects the arma-
ture from excessive speed until the switch is opened, at
which time the return spring causes the pinion to disen-
gage. To prevent excessive overrun, the switch should be
released immediately after the engine starts.
STARTING SYSTEM
The engine electrical system includes the battery, the igni-
tion, the starter, the generator, and all the related wiring.
Diagnostic tables will aid in troubleshooting system faults.
When a fault is traced to a particular component, refer to
that component section of the service manual.
The starting system circuit consists of the battery, the
starter motor, the ignition switch, and all the related electri-
cal wiring. All of these components are connected electri-
cally.

SECTION : 1F
ENGINE CONTROLS
CAUTION : Disconnect the negative battery cable before removing or installing any electrical unit o r w hen a
tool or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will
help prevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise
noted.
TABLE OF CONTENTS
SPECIFICATIONS1F–6 . . . . . . . . . . . . . . . . . . . . . . . . . .
Engine Data Display Tables 1F–6. . . . . . . . . . . . . . . . .
Engine Data Display Table Definitions 1F–7. . . . . . . .
Fastener Tightening Specifications 1F–10. . . . . . . . .
Fuel System Specifications 1F–11. . . . . . . . . . . . . . . . .
Temperature Vs Resistance 1F–11. . . . . . . . . . . . . . . .
SCHEMATIC AND ROUTING DIAGRAMS1F–12 . . . .
ECM Wiring Diagram
(1.4L/1.6L DOHC – 1 OF 6) 1F–12. . . . . . . . . . . . . .
ECM Wiring Diagram
(1.4L/1.6L DOHC – 2 OF 6) 1F–13. . . . . . . . . . . . . .
ECM Wiring Diagram
(1.4L/1.6L DOHC – 3 OF 6) 1F–14. . . . . . . . . . . . . .
ECM Wiring Diagram
(1.4L/1.6L DOHC – 4 OF 6) 1F–15. . . . . . . . . . . . . .
ECM Wiring Diagram
(1.4L/1.6L DOHC – 5 OF 6) 1F–16. . . . . . . . . . . . . .
ECM Wiring Diagram
(1.4L/1.6L DOHC – 6 OF 6) 1F–17. . . . . . . . . . . . . .
ECM Wiring Diagram (1.8L DOHC – 1 OF 6) 1F–18.
ECM Wiring Diagram (1.8L DOHC – 2 OF 6) 1F–19.
ECM Wiring Diagram (1.8L DOHC – 3 OF 6) 1F–20.
ECM Wiring Diagram (1.8L DOHC – 4 OF 6) 1F–21.
ECM Wiring Diagram (1.8L DOHC – 5 OF 6) 1F–22.
ECM Wiring Diagram (1.8L DOHC – 6 OF 6) 1F–23.
Connector End View 1F–24. . . . . . . . . . . . . . . . . . . . . .
COMPONENT LOCATOR1F–28 . . . . . . . . . . . . . . . . . . .
Component Locator (1.4L/1.6L DOHC) 1F–28. . . . . .
Component Locator (1.8L DOHC) 1F–29. . . . . . . . . . .
DIAGNOSIS1F–30 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SYSTEM DIAGNOSIS 1F–30. . . . . . . . . . . . . . . . . . . . . .
Diagnostic Aids 1F–30. . . . . . . . . . . . . . . . . . . . . . . . . . .
Idle Learn Procedure 1F–30. . . . . . . . . . . . . . . . . . . . . .
TEC (Tooth Error Correction) Learn Procedure 1F–31ON–Board Diagnostic (EOBD) System Check
(1.4L/1.6L DOHC) 1F–32. . . . . . . . . . . . . . . . . . . . . . .
ON–Board Diagnostic (EOBD) System Check
(1.8L DOHC) 1F–34. . . . . . . . . . . . . . . . . . . . . . . . . . .
Multiple ECM Informationn Sensor Dtcs Set 1F–36. .
Engine Cranks But Will Not Run
(1.4L/1.6L DOHC) 1F–40. . . . . . . . . . . . . . . . . . . . . . .
Engine Cranks But Will Not Run (1.8L DOHC) 1F–47
No Malfunction Indicator Lamp (
1.4L/1.6L DOHC) 1F–54. . . . . . . . . . . . . . . . . . . . . . .
No Malfunction Indicator Lamp (1.8L DOHC) 1F–56.
Malfunction Indicator Lamp On Steady (1.4L/1.6L
DOHC) 1F–58. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Malfunction Indicator Lamp On Steady
(1.8L DOHC) 1F–60. . . . . . . . . . . . . . . . . . . . . . . . . . .
Fuel System Diagnosis 1F–62. . . . . . . . . . . . . . . . . . . .
Fuel Pump Relay Circuit Check
(1.4L/1.6L DOHC) 1F–65. . . . . . . . . . . . . . . . . . . . . . .
Fuel Pump Relay Circuit Check (1.8L DOHC) 1F–68.
Main Relay Circuit Check (1.4L/1.6L DOHC) 1F–71.
Main Relay Circuit Check (1.8L DOHC) 1F–73. . . . . .
Manifold Absolute Pressure Check
(1.4L/1.6L DOHC) 1F–75. . . . . . . . . . . . . . . . . . . . . . .
Manifold Absolute Pressure Check
(1.8L DOHC) 1F–77. . . . . . . . . . . . . . . . . . . . . . . . . . .
Idle Air Control System Check
(1.4L/1.6L DOHC) 1F–79. . . . . . . . . . . . . . . . . . . . . . .
Idle Air Control System Check (1.8L DOHC) 1F–82. .
Ignition System Check (1.4L/1.6L DOHC) 1F–85. . . .
Ignition System Check (1.8L DOHC) 1F–88. . . . . . . .
Engine Cooling Fan Circuit Check – Dual Fan
(1.4L/1.6L DOHC) 1F–93. . . . . . . . . . . . . . . . . . . . . . .
Engine Cooling Fan Circuit Check – Dual Fan
(1.8L DOHC) 1F–100. . . . . . . . . . . . . . . . . . . . . . . . . .
Data Link Connector Diagnosis
(1.4L/1.6L DOHC) 1F–106. . . . . . . . . . . . . . . . . . . . . .
Data Link Connector Diagnosis (1.8L DOHC) 1F–108
Fuel Injector Balance Test 1F–110. . . . . . . . . . . . . . . .

1F – 2IENGINE CONTROLS
DAEWOO V–121 BL4
TROUBLE CODE DIAGNOSIS
(1.4L/1.6L DOHC) 1F–111. . . . . . . . . . . . . . . . . . . . . . . .
Clearing Trouble Codes 1F–111. . . . . . . . . . . . . . . . . . . .
Diagnostic Trouble Codes (1.4L/1.6L DOHC) 1F–111.
DTC P0107 Manifold Absolute Pressure Sensor
Low Voltage 1F–114. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0108 Manifold Absolute Pressure Sensor
High Voltage 1F–117. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0112 Intake Air Temperature Sensor Low
Voltage 1F–120. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0113 Intake Air Temperature Sensor High
Voltage 1F–122. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0117 Engine Coolant Temperature
Sensor Low Voltage 1F–125. . . . . . . . . . . . . . . . . . . .
DTC P0118 Engine Coolant Temperature
Sensor High Voltage 1F–128. . . . . . . . . . . . . . . . . . . .
DTC P0122 Throttle Position Sensor Low
Voltage 1F–131. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0123 Throttle Position Sensor High
Voltage 1F–134. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0131 Front Heated Oxygen Sensor Low
Voltage 1F–137. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0132 Front Heated Oxygen Sensor High
Voltage 1F–140. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0133 Front Heated Oxygen Sensor No
Activity 1F–142. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0135 Front Heated Oxygen Sensor Heater
Circuit Not Functioning 1F–145. . . . . . . . . . . . . . . . . .
DTC P0137 Rear Heated Oxygen Sensor Low
Voltage 1F–148. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0138 Rear Heated Oxygen Sensor High
Voltage 1F–151. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0140 Rear Heated Oxygen Sensor No
Activity 1F–153. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0141 Rear Heated Oxygen Sensor Heater
Malfunction 1F–156. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0171 Fuel Trim System Too Lean 1F–158. . . .
DTC P0172 Fuel Trim System Too Rich 1F–162. . . . .
DTC P0222 Main Throttle Idle Actuator (MTIA)
Low Voltage 1F–165. . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0223 Main Throttle Idle Actuator (MTIA)
High Voltage 1F–168. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0261 Injector 1 Low Voltage 1F–171. . . . . . . . .
DTC P0262 Injector 1 High Voltage 1F–173. . . . . . . .
DTC P0264 Injector 2 Low Voltage 1F–175. . . . . . . . .
DTC P0265 Injector 2 High Voltage 1F–177. . . . . . . .
DTC P0267 Injector 3 Low Voltage 1F–179. . . . . . . . .
DTC P0268 Injector 3 High Voltage 1F–181. . . . . . . .
DTC P0270 Injector 4 Low Voltage 1F–183. . . . . . . . .
DTC P0271 Injector 4 High Voltage 1F–185. . . . . . . . DTC P0300 Multiple Cylinder Misfire(Catalyst
Damage) 1F–188. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0300 Multiple Cylinder Misfire(Increase
Emission) 1F–192. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0327 Knock Sensor Circuit Fault
(1.4L DOHC) 1F–195. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0327 Knock Sensor Circuit Fault
(1.6L DOHC) 1F–198. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0335 Magnetic Crankshaft Position
Sensor Electrical Error 1F–201. . . . . . . . . . . . . . . . . .
DTC P0336 58X Crankshaft Position Sensor
No Plausible Signal 1F–204. . . . . . . . . . . . . . . . . . . .
DTC P0337 58X Crankshaft Position Sensor
No Signal 1F–207. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0341 Camshaft Position Sensor
Rationality 1F–210. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0342 Camshaft Position Sensor Signal 1F–212
DTC P0351 Ignition Signal Coil A Fault 1F–214. . . . .
DTC P0352 Ignition Signal Coil B Fault 1F–216. . . . .
DTC P0400 Exhaust Gas Recirculation Out
Of Limit 1F–218. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0404 Exhaust Gas Recirculation
Opened 1F–221. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0405 EGR Pintle Position Sensor Low
Voltage 1F–224. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0406 EGR Pintle Position Sensor High
Voltage 1F–227. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0420 Catalyst Low Efficiency 1F–230. . . . . . . .
DTC P0444 EVAP Purge Control Circuit No
Signal 1F–232. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0445 EVAP Purge Control Circuit Fault 1F–235
DTC P0462 Fuel Level Sensor Low Voltage
(1.6L DOHC Only) 1F–238. . . . . . . . . . . . . . . . . . . . .
DTC P0463 Fuel Level Sensor High Voltage
(1.6L DOHC Only) 1F–241. . . . . . . . . . . . . . . . . . . . .
DTC P0480 Low Speed Cooling Fan Relay
Circuit Fault (1.4L DOHC) 1F–245. . . . . . . . . . . . . . .
DTC P0480 Low Speed Cooling Fan Relay
Circuit Fault (1.6L DOHC) 1F–248. . . . . . . . . . . . . . .
DTC P0481 High Speed Cooling Fan Relay
Circuit Fault (1.4L DOHC) 1F–251. . . . . . . . . . . . . . .
DTC P0481 High Speed Cooling Fan Relay
Circuit Fault (1.6L DOHC) 1F–254. . . . . . . . . . . . . . .
DTC P0501 Vehicle Speed No Signal
(M/T Only) 1F–257. . . . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0510 Throttle Position Switch Circuit Fault
(1.4L DOHC) 1F–260. . . . . . . . . . . . . . . . . . . . . . . . . .
DTC P0510 Throttle Position Switch Circuit
Fault (1.6L DOHC) 1F–262. . . . . . . . . . . . . . . . . . . . .
DTC P0532 A/C Pressure Sensor Low Voltage 1F–264
DTC P0533 A/C Pressure Sensor High
Voltage 1F–267. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1F – 30IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSIS
SYSTEM DIAGNOSIS
DIAGNOSTIC AIDS
If an intermittent problem is evident, follow the guidelines
below.
Preliminary Checks
Before using this section you should have already per-
formed the ”On–Board Diagnostic System Check.”
Perform a thorough visual inspection. This inspection can
often lead to correcting a problem without further checks
and can save valuable time. Inspect for the following con-
ditions:
S Engine control module (ECM) grounds for being
clean, tight, and in their proper location.
S Vacuum hoses for splits, kinks, collapsing and prop-
er connections as shown on the Vehicle Emission
Control Information label. Inspect thoroughly for
any type of leak or restriction.
S Air leaks at the throttle body mounting area and the
intake manifold sealing surfaces.
S Ignition wires for cracks, hardness, proper routing,
and carbon tracking.
S Wiring for proper connections.
S Wiring for pinches or cuts.
Diagnostic Trouble Code Tables
Do not use the Diagnostic Trouble Code (DTC) tables to
try to correct an intermittent fault. The fault must be pres-
ent to locate the problem.
Incorrect use of the DTC tables may result in the unneces-
sary replacement of parts.
Faulty Electrical Connections or Wiring
Most intermittent problems are caused by faulty electrical
connections or wiring. Perform a careful inspection of sus-
pect circuits for the following:
S Poor mating of the connector halves.
S Terminals not fully seated in the connector body.
S Improperly formed or damaged terminals. All con-
nector terminals in a problem circuit should be care-
fully inspected, reformed, or replaced to insure con-
tact tension.S Poor terminal–to–wire connection. This requires
removing the terminal from the connector body.
Road Test
If a visual inspection does not find the cause of the prob-
lem, the vehicle can be driven with a voltmeter or a scan
tool connected to a suspected circuit. An abnormal voltage
or scan tool reading will indicate that the problem is in that
circuit.
If there are no wiring or connector problems found and a
DTC was stored for a circuit having a sensor, except for
DTC P0171 and DTC P0172, replace the sensor.
Fuel System
Some intermittent driveability problems can be attributed
to poor fuel quality. If a vehicle is occasionally running
rough, stalling, or otherwise performing badly, ask the cus-
tomer about the following fuel buying habits:
S Do they always buy from the same source? If so,
fuel quality problems can usually be discounted.
S Do they buy their fuel from whichever fuel station
that is advertising the lowest price? If so, check the
fuel tank for signs of debris, water, or other contam-
ination.
IDLE LEARN PROCEDURE
Whenever the battery cables, the engine control module
(ECM), or the ECM fuse is disconnected or replaced, the
following idle learn procedure must be performed:
1. Turn the ignition ON for 5 seconds.
2. Turn the ignition OFF for 5 seconds.
3. Turn the ignition ON for 5 seconds.
4. Start the engine in park/neutral.
5. Allow the engine to run until the engine coolant is
above 185° F (85°C ).
6. Turn the A/C ON for 10 seconds, if equipped.
7. Turn the A/C OFF for 10 seconds, if equipped.
8. If the vehicle is equipped with an automatic trans-
axle, apply the parking brake. While pressing the
brake pedal, place the transaxle in D (drive).
9. Turn the A/C ON for 10 seconds, if equipped.
10. Turn the A/C OFF for 10 seconds, if equipped.
11. Turn the ignition OFF. The idle learn procedure is
complete.

1F – 32IENGINE CONTROLS
DAEWOO V–121 BL4
ON–BOARD DIAGNOSTIC (EOBD) SYSTEM CHECK
(1.4L/1.6L DOHC)
Circuit Description
The On–Board Diagnostic (EOBD) system check is the
starting point for any driveability complaint diagnosis. Be-
fore using this procedure, perform a careful visual/physi-
cal check of the engine control module (ECM) and the en-
gine grounds for cleanliness and tightness.
The EOBD system check is an organized approach to
identifying a problem created by an electronic engine con-
trol system malfunction.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed–through wire insulation or a wire broken inside the
insulation. Check for poor connections or a damaged har-
ness. Inspect the ECM harness and connections for im-
proper mating, broken locks, improperly formed or dam-
aged terminals, poor terminal–to–wire connection, and
damaged harness.Test Description
Numbers below refer to the step number on the Diagnostic
Chart:
1. The Malfunction Indicator Lamp (MIL) should be
ON steady with the ignition ON and the engine
OFF. If not, go to ”Diagnostic Aids”.
2. Checks the Class 2 data circuit and ensures that
the ECM is able to transmit serial data.
3. This test ensures that the ECM is capable of con-
trolling the MIL and the MIL driver circuit is not
shorted to ground.
4. If the engine will not start, refer to ”Engine Cranks
But Will Not Run” in this section.
7. A scan tool parameter which is not within the typical
range may help to isolate the area which is causing
the problem.
10. This vehicle is equipped with a ECM which utilizes
an Electrically Erasable Programmable Read Only
Memory (EEPROM). The replacement ECM must
be programmed. Refer to the latest Techline proce-
dure for ECM reprogramming.

1F – 34IENGINE CONTROLS
DAEWOO V–121 BL4
ON–BOARD DIAGNOSTIC (EOBD) SYSTEM CHECK
(1.8L DOHC)
Circuit Description
The On–Board Diagnostic (EOBD) system check is the
starting point for any driveability complaint diagnosis. Be-
fore using this procedure, perform a careful visual/physi-
cal check of the engine control module (ECM) and the en-
gine grounds for cleanliness and tightness.
The EOBD system check is an organized approach to
identifying a problem created by an electronic engine con-
trol system malfunction.
Diagnostic Aids
An intermittent may be caused by a poor connection,
rubbed–through wire insulation or a wire broken inside the
insulation. Check for poor connections or a damaged har-
ness. Inspect the ECM harness and connections for im-
proper mating, broken locks, improperly formed or dam-
aged terminals, poor terminal–to–wire connection, and
damaged harness.Test Description
Numbers below refer to the step number on the Diagnostic
Chart:
1. The Malfunction Indicator Lamp (MIL) should be
ON steady with the ignition ON and the engine
OFF. If not, go to”Diagnostic Aids”.
2. Checks the Class 2 data circuit and ensures that
the ECM is able to transmit serial data.
3. This test ensures that the ECM is capable of con-
trolling the MIL and the MIL driver circuit is not
shorted to ground.
4. If the engine will not start, refer to ”Engine Cranks
But Will Not Run” in this section.
7. A scan tool parameter which is not within the typical
range may help to isolate the area which is causing
the problem.
10. This vehicle is equipped with a ECM which utilizes
an Electrically Erasable Programmable Read Only
Memory (EEPROM). The replacement ECM must
be programmed. Refer to the latest Techline proce-
dure for ECM reprogramming.

1F – 40IENGINE CONTROLS
DAEWOO V–121 BL4
ENGINE CRANKS BUT WILL NOT RUN (1.4L/1.6L DOHC)
Test Description
The number(s) below refer to step(s) on the diagnostic
table.
1. The On–Board Diagnostic (EOBD) System Check
prompts the technician to complete some basic
checks and store the freeze frame and failure re-
cords data on the scan tool if applicable. This
creates an electronic copy of the data taken when
the occurred. The information is then stored on the
scan tool for later reference.
2. By performing a compression test, it can be deter-
mined if the engine has the mechanical ability to
run.
3. It is important to check for the presence of sparkfrom all of the ignition wires. If spark is present from
one to three of the ignition coil terminals, the Crank-
shaft Position (CKP) sensor is OK.
19. In checking the engine control module (ECM) out-
puts for the electronic spark timing signal, it recom-
mended to use an oscilloscope to view the varying
voltage signals. In measuring these outputs with a
voltmeter, intermittent errors may occur that cannot
be seen by a voltmeter.
35. This step checks for proper operation of the ECM’s
control of the fuel pump circuit.
59. This step checks for a ground signal being supplied
by the ECM to operate the fuel injectors. If there is
no ground present during the cranking of the en-
gine, and the fuel injector wiring is OK, the ECM is
at fault.
Engine Cranks But Will Not Run (1.4L/1.6L DOHC)
CAUTION : Use only electrically insulated pliers when
handling ignition wires with the engine running to
prevent an electrical shock.
CAUTION : Do not pinch or restrict nylon fuel lines.Damage to the lines could cause a fuel leak, resulting
in possible fire or personal injury.
Step
ActionValue(s)YesNo
1Perform an Euro On–Board Diagnostic (EOBD)
System Check.
Is the check complete.–Go to Step 2Go to
”Euro On–
Board Diagnos-
tic System
Check”
2Crank the engine.
Does the engine start and continue to run?–System OKGo to Step 3
3Perform a cylinder compression test.
Is the cylinder compression for all of the cylinders at
or above the value specified?689 kPa
(100 psi)Go to Step 7Go to Step 4
4Inspect the timing belt alignment.
Is the timing belt in alignment?–Go to Step 6Go to Step 5
5Align or replace the timing belt as needed.
Is the repair complete?–Go to Step 2–
6Repair internal engine damage as needed.
Is the repair complete?–Go to Step 2–
7Inspect the fuel pump fuse.
Is the problem found?–Go to Step 8Go to Step 9
8Replace the fuse.
Is the repair complete?–Go to Step 2–
9Check for the presence of spark from all of the igni-
tion wires while cranking the engine.
Is spark present from all of the ignition wires?–Go to Step 23Go to Step 10
101. Measure the resistance of the ignition wires.
2. Replace any of the ignition wire(s) with a resist-
ance above the value specified.
3. Check for the presence of spark from all of the
ignition wire.
Is spark present from all of the ignition wires?30000 WGo to Step 2Go to Step 11

ENGINE CONTROLS 1F – 41
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
111. Turn the ignition OFF.
2. Disconnect the crankshaft position (CKP) sen-
sor connector.
3. Turn the ignition ON.
4. Measure the voltage between following termi-
nals:
S Terminal 1 and 3 of the CKP sensor con-
nector.
S Terminal 2 and 3 of the CKP sensor con-
nector.
S Terminal 1 of the CKP sensor connector
and ground.
S Terminal 2 of the CKP sensor connector
and ground.
Are the voltage measure within the value specified?
1.4 VGo to Step 13Go to Step 12
12Check for an open or short in the wires between CKP
sensor connector and ECM connector and repair as
need.
Is the repair complete?–Go to Step 2–
131. Disconnect electronic Ignition (EI) system igni-
tion coil connector to prevent the vehicle from
starting.
2. Measure the voltage at ECM connector termi-
nal 85 and 54 by backprobing the ECM con-
nector.
Are the voltage readings near the value specified?1.4V with
ignition ON,
1.6V during
crankingGo to Step 15Go to Step 14
14Replace the CKP sensor.
Is the repair complete?–Go to Step 2–
151. Turn the ignition OFF.
2. Disconnect the electrical connector at EI sys-
tem ignition coil.
3. Connect a test light between terminal 2 of the
EI system ignition coil connector and ground.
4. Turn the ignition ON.
Is the test light on?–Go to Step 17Go to Step 16
16Check for open in wire between the battery and EI
system ignition coil connector terminal 2 and repair
as needed.
Is the repair complete?–Go to Step 2–
171. Turn the ignition OFF.
2. Disconnect ECM connect and EI system igni-
tion coil connector.
3. Measure the resistance between following ter-
minals:
S Terminal 1 of ignition coil and terminal 31 of
ECM connector.
S Terminal 1 of ignition coil and terminal 32 of
ECM connector.
Are the resistance within the value specified?0 WGo to Step 19Go to Step 18
18Check for open circuit and repair as needed.
Is the repair complete?–Go to Step 2–