2004 DAEWOO LACETTI fuses

4F – 60IANTILOCK BRAKE SYSTEM
DAEWOO V–121 BL4
MAINTENANCE AND REPAIR
ON–VEHICLE SERVICE
SERVICE PRECAUTIONS
CAUTION : Brake fluid may irritate eyes and skin. In
case of contact, take the following actions:
S Eye contact – rinse thoroughly with water.
S Skin contact – wash with soap and water.
S Ingestion – consult a physician immediately.
CAUTION : To help avoid personal injury due to poor
braking, DO NOT tap into the vehicle’s brake system
to operate a trailer brake system.
Notice : When fasteners are removed, always reinstall
them at the same location from which they were removed.
If a fastener needs to be replaced, use the correct part
number fastener for that application. If the correct part
number fastener is not available, a fastener of equal size
and strength (or stronger) may be used. Fasteners that
are not reused, and those requiring thread–locking com-
pound will be called out. The correct torque values must
be used when installing fasteners that require them. If the
above procedures are not followed, parts or system dam-
age could result.
Notice : Use only DOT 3 equivalent hydraulic brake fluid.
The use of DOT 5 (silicone) brake fluid is not recom-
mended. Reduced brake performance or durability may
result.
Notice : Avoid spilling brake fluid on any of the vehicle’s
painted surfaces, wiring, cables, or electrical connectors.
Brake fluid will damage paint and electrical connections.
If any fluid is spilled on the vehicle, flush the area with wa-
ter to lessen the damage.
Computer System Service Precautions
Take care to avoid electronic brake control module
(EBCM) circuit overloading. In testing for opens or shorts,
do not ground or apply voltage to any circuit unless
instructed to do so by the diagnostic procedure. Test cir-
cuits only with a high–impedance multimeter. Never re-
move or apply power to any control module with the igni-
tion switch in the ON position. Always turn the ignition to
the OFF position before removing or connecting battery
cables, fuses, or connectors.
General Service Precautions
S Disconnect the EBCM connector before performing
any vehicle welding work using an electric arc weld-
er.
S Do not attempt to disassemble any component des-
ignated as nonserviceable. The hydraulic modulator
and the EBCM can be separated from each other
and replaced separately but cannot be serviced.
They have no replaceable parts, and there is no
access to the components they contain.

ANTILOCK BRAKE SYSTEM 4F – 65
DAEWOO V–121 BL4
GENERAL DESCRIPTION AND SYSTEM
OPERATION
BASIC KNOWLEDGE REQUIRED
Before using this section, it is important that you have a ba-
sic knowledge of the following items. Without this knowl-
edge, it will be difficult to use the diagnostic procedures
contained in this section.
S Basic Electrical Circuits : You should understand
the basic theory of electricity and know the mean-
ing of voltage, current (amps), and resistance
(ohms). You should understand what happens in a
circuit with an open or shorted wire. You should be
able to read and understand a wiring diagram.
S Use of Circuit Testing Tools : You should know how
to use a test light and how to bypass components
to test circuits using fused jumper wires. You should
be familiar with a digital multimeter. You should be
able to measure voltage, resistance, and current,
and be familiar with the controls and how to use
them correctly.
ABS SYSTEM COMPONENTS
The ABS 5.3 Antilock Braking System (ABS) consists of
a conventional hydraulic brake system plus antilock com-
ponents. The conventional brake system includes a vacu-
um booster, master cylinder, front disc brakes, rear lead-
ing/trailing drum brakes, interconnecting hydraulic brake
pipes and hoses, brake fluid level sensor and the BRAKE
indicator.
The ABS components include a hydraulic unit, an elec-
tronic brake control module (EBCM), two system fuses,
four wheel speed sensors (one at each wheel), intercon-
necting wiring, the ABS indicator, the EBD indicator (which
is connected to the parking lamp) and the rear disk brakes.
See “ABS Component Locator” in this section for the gen-
eral layout of this system.
The hydraulic unit with the attached EBCM is located be-
tween the surge tank and the fire wall on the left side of the
vehicle.
The basic hydraulic unit configuration consists of hydraulic
check valves, two solenoid valves for each wheel, a hy-
draulic pump, two accumulators, and two damper. The hy-
draulic unit controls hydraulic pressure to the front calipers
and rear wheel cylinders by modulating hydraulic pressure
to prevent wheel lockup.
Nothing in the hydraulic unit or the EBCM is serviceable.
In the event of any failure, the entire ABS unit with at-
tached EBCM must be replaced. For more information, re-
fer to ”Base Braking Mode” and ”Antilock Braking Mode”
in this section.
BASE BRAKING MODE
The baseline braking mode of the ABS 5.3 system used
in this vehicle is a diagonal split system. In this system,
one master cylinder circuit supplies pressure to the right
front and the left rear brakes; the other circuit supplies
pressure to the left front and the right rear brakes. All
valves in the hydraulic modulator are in their normal, non–
energized positions as shown in the drawings found in
”ABS System Components” in this section.

ANTILOCK BRAKE SYSTEM 4F – 71
DAEWOO V–121 BL4
TIRES AND ABS/EBD
Replacement Tires
Tire size is important for proper performance of the ABS
system. Replacement tires should be the same size, load
range, and construction as the original tires. Replace tires
in axle sets and only with tires of the same tire perfor-
mance criteria (TPC) specification number. Use of any
other size or type may seriously affect the ABS operation.
TIRES AND ABS/EBD
Notice : There is no serviceable or removable EEPROM.
The EBCM must be replaced as an assembly.
The EBCM is attached to the hydraulic unit in the engine
compartment. The controlling element of ABS 5.3 is a mi-
croprocessor–based EBCM. Inputs to the system include
the four wheel speed sensors, the stoplamp switch, the
ignition switch, and the unswitched battery voltage. There
is an output to a bi–directional serial data link, located in
pin K of Data Link Connector (DLC) for service diagnostic
tools and assembly plant testing.
The EBCM monitors the speed of each wheel. If any wheel
begins to approach lockup and the brake switch is closed
(brake pedal depressed), the EBCM controls the sole-
noids to reduce brake pressure to the wheel approaching
lockup. Once the wheel regains traction, brake pressure
is increased until the wheel again begins to approach lock-
up. This cycle repeats until either the vehicle comes to a
stop, the brake pedal is released, or no wheels approach
lockup.
Additionally, the EBCM monitors itself, each input (except
the serial data link), and each output for proper operation.
If it detects any system malfunction, the EBCM will store
a DTC in nonvolatile memory (EEPROM) (DTCs will not
disappear if the battery is disconnected). Refer to ”Self
Diagnostics” in this section for more detailed information.
FRONT WHEEL SPEED SENSOR
The front wheel speed sensors are of a variable reluctance
type. Each sensor is attached to the steering knuckle,
close to a toothed ring. The result, as teeth pass by the
sensor, is an AC voltage with a frequency proportional to
the speed of the wheel. The magnitude of the voltage and
frequency increase with increasing speed. The sensor is
not repairable, nor is the air gap adjustable.
FRONT WHEEL SPEED SENSOR
RINGS
The toothed ring mentioned above is pressed onto the
wheel–side (outer) constant velocity joint. Each ring con-
tains 47 equally spaced teeth. Exercise care during ser-
vice procedures to avoid prying or contacting this ring. Ex-cessive contact may cause damage to one or more teeth.
If the ring is damaged, the wheel–side constant velocity
joint must be replaced.
REAR WHEEL SPEED SENSOR AND
RINGS
The rear wheel speed sensors operate in the same man-
ner as the front wheel speed sensors. They incorporate a
length of flexible harness with the connector attached to
the end of the harness. The rear wheel speed rings are in-
corporated into the hub assemblies and cannot be re-
placed separately, but require replacement of the rear
hub/bearing assembly.
VALUE RELAY AND PUMP MOTOR
RELAY
The valve relay and the motor pump relay are located in-
side the electronic brake control module (EBCM) and are
not replaceable. If one should fail, replace the EBCM.
WIRING HARNESS
The wiring harness is the mechanism by which the elec-
tronic brake control module (EBCM) is electrically con-
nected to power and to ground, to the wheel speed sen-
sors, the fuses, the switches, the indicators, and the serial
communications port. The components, considered part
of the wiring harness, are the wires that provide electrical
interconnection, and connectors (terminals, pins, con-
tacts, or lugs) that provide an electrical/mechanical inter-
face from the wire to a system component.
INDICATORS
The electronic brake control module (EBCM) continuously
monitors itself and the other ABS components. If the
EBCM detects a problem with the system, the amber ABS
indicator will light continuously to alert the driver to the
problem. An illuminated ABS indicator indicates that the
ABS system has detected a problem that affects the op-
eration of ABS. No antilock braking will be available. Nor-
mal, non–antilock brake performance will remain. In order
to regain ABS braking ability, the ABS must be serviced.
The red BRAKE indicator will be illuminated when the sys-
tem detects a low brake fluid level in the master cylinder
or when the parking brake switch is closed (the parking
brake is engaged) or EBD system is diabled.
WARNING : EBD INDICATOR LAMP WIRING IS CON-
NECTED TO THE PARKING BRAKE LAMP. IF THE
PARKING BRAKE LAMP IS TURNED ON WHEN YOU
DRIVING, CHECKING ON WHETHER THE PARKING
BRAKE LEVER IS ENAGED OR THE BRAKE FLUID
LEVEL IS LOW. IF THE SYSTEM HAS NO PROBLEM,
THE EBD SYSTEM IS WORKING IMPROPERLY. THE
EBD SYSTEM MUST BE SERVICED.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 133
DAEWOO V–121 BL4
DTC P1606 – Failure Of External Watchdog
StepActionValue(s)YesNo
1Perform an On–Board Diagnostic (EOBD) System
Check.
Is the check completed?–Go to Step 2Go to ”On–
Board Diagnos-
tic System
Check”
21. Install the scan tool.
2. Turn the ignition ON, with the engine OFF.
Does the scan tool display P1606?–Go to Step 3Go to ”Diag-
nostic Aids”
3Inspect EF1 or F2 fuse for open.
Was a problem found?–Go to Step 4Go to Step 5
4Replace the fuse as necessary.
Is the action completed?–System OK–
51. Turn the ignition OFF.
2. Disconnect the TCM wiring connector.
3. Inspect the wiring harness for short to battery
between the fuses (EF1 or F2) and the TCM
terminals (B3, C15, or C16).
Was a problem found?–Repair the wir-
ing harness.Go to Step 6
6Inspect the wiring harness for open between the
fuses (EF1 or F2) and the TCM terminals (B3, C15
or C16).
Was a problem found?–Repair the wir-
ing harness.Go to Step 7
7Inspect the wiring harness for open or short to
ground between TCM terminals (B12 or B13) and
G201.
Was a problem found?–Repair the wir-
ing harness.Go to Step 8
8Inspect the wiring harness for short to power be-
tween the terminals (B12 or B13) and G201.
Was a problem found?–Repair the wir-
ing harness.Go to Step 9
9Replace the TCM.
Is the replacement complete?–Go to Step 10–
101. Using the scan tool, clear the DTCs.
2. Road test the vehicle within the conditions for
setting this DTC as specified in the text.
Does the scan tool indicate that this diagnostic has
run and passed?–Go to Step 11Go to Step 2
111. Check if any DTCs are set.
2. Are any DTCs displayed that have not been
diagnosed?–Go to ”Applica-
ble DTC table”System OK

9B – 16ILIGHTING SYSTEMS
DAEWOO V–121 BL4
HEADLAMPS
Low–Beam Headlamps Are Inoperative, High–Beam Headlamps
Are OK
StepActionValue(s)YesNo
1Check fuses Ef20 (left side headlamps) and Ef27
(right side headlamps).
Is fuse Ef20 or Ef27 blown?–Go to Step 2Go to Step 3
21. Check for a short circuit and repair if neces-
sary.
2. Replace the fuse.
Is the repair complete?–System OK–
3Check the voltage at fuses Ef20 and Ef27.
Does the voltage available at fuses Ef20 and Ef27
equal the value specified?11–14 vGo to Step 4Go to Step 9
41. Disconnect both headlamp connectors.
2. Turn the headlamps ON.
3. Select the low beams.
Does the voltage at each headlamp connector termi-
nal 5 equal the value specified?11–14 vGo to Step 6Go to Step 5
5Repair the open circuit between fuses Ef20 or Ef27
and the low beam headlamps.
Is the repair complete?–System OK–
61. Disconnect the headlamp connectors.
2. Connect an ohmmeter between ground and
either headlamp connector terminal 6.
Is the resistance equal to the value specified?0 WGo to Step 8Go to Step 7
7Repair the ground circuit.
Is the repair complete?–System OK–
8Replace the faulty headlamps.
Is the repair complete?–System OK–
91. Disconnect the headlamp switch connector.
2. Select the low beams.
3. Use an ohmmeter to check the continuity be-
tween terminals 6 and 5 of the headlamp
switch.
Does the ohmmeter indicate the value specified?0 WGo to Step 10Go to Step 11
10Replace the headlamp combination switch.
Is the repair complete?–System OK–
11Repair the open circuit between fuses Ef20 and Ef27
and the headlamp switch connector terminal 5.
Is the repair complete?–System OK–

LIGHTING SYSTEMS 9B – 17
DAEWOO V–121 BL4
High–Beam Headlamps Are Inoperative, Low–Beam Headlamps
Are OK
StepActionValue(s)YesNo
1Check the high–beam headlamps in the ”flash–to–
pass” mode.
Do the high–beam headlamps work in the ”flash–to–
pass” mode?–Go to Step 11Go to Step 2
2Check the voltage at the headlamp switch connector
terminal 7.
Does the voltage equal the value specified?11–14 vGo to Step 4Go to Step 3
3Repair the open circuit between the headlamp
switch connector terminal 7 and the fuse Ef2.
Is the repair complete?–System OKGo to Step 4
4Check fuses Ef15.
Is the fuse blown?–Go to Step 5Go to Step 6
51. Check for a short circuit. Repair it if necessary.
2. Replace the fuse.
Is the repair complete?–System OK–
61. Turn the high–beam headlamps ON.
2. Check the voltage at fuses Ef15.
Does the voltage available at fuses Ef15 equal the
value specified?11–14 vGo to Step 7Go to Step 12
71. Turn the high–beam headlamps ON.
2. Check the voltage at headlamp terminal 4 with
high beams selected.
Does the voltage available at the headlamp connec-
tor terminal 4 equal the value specified?11–14 vGo to Step 9Go to Step 8
8Repair the open circuit between fuse EF16 and the
high–beam headlamps.
Is the repair complete?–System OK–
9Replace the faulty headlamps.
Is the repair complete?–System OK–
101. Disconnect the headlamp combination switch
connector.
2. Put the switch in the high–beam position.
3. Use an ohmmeter to check the continuity of the
headlamp switch between terminals 7 and 4.
Does the ohmmeter indicate the specified value?0 WGo to Step 12Go to Step 11
11Replace the headlamp combination switch.
Is the repair complete?–System OK–
12Repair the open circuit between headlamp combina-
tion switch connector (terminal 4) and Ef15.
Is the repair complete?–System OK–

9B – 18ILIGHTING SYSTEMS
DAEWOO V–121 BL4
High–Beam and Low–Beam Headlamps Are Inoperative On Both
Left and Right Sides
StepActionValue(s)YesNo
1Check fuses F6, Ef2, Ef20, Ef27 and Ef15.
Is any fuse blown?–Go to Step 2Go to Step 3
21. Check for a short circuit and repair if neces-
sary.
2. Replace the fuse.
Is the repair complete?–System OK–
31. Turn the low–beam headlamps ON.
2. Check the voltage at fuses Ef20, Ef27 and
Ef15.
Does the voltage at the headlamps equal the value
specified?11–14 vGo to Step 4Go to Step 9
41. Turn the low–beam headlamps ON.
2. Check the voltage at the headlamp connector
terminal 5.
3. Turn the high–beam headlamps ON.
4. Check the voltage at headlamp connector ter-
minal 4.
Does the battery voltage available at the headlamps
equal the value specified?11–14 vGo to Step 6Go to Step 5
5Repair the open circuit between fuses Ef20, Ef27
and Ef15 and the headlamps.
Is the repair complete?–System OK–
6Use an ohmmeter to check between ground and
each headlamp connector terminal 6.
Is the resistance equal to the specified value?0 WGo to Step 8Go to Step 7
7Repair the ground circuit.
Is the repair complete?–System OK–
81. Replace the faulty headlamps.
2. Check the charging system to make sure that
charging voltage is not excessively high. Re-
pair if necessary.
Is the repair complete?–System OK–
9Temporarily substitute the illumination relay in place
of the headlamp relay.
Do the headlamps operate with the substituted
relay?–Go to Step 10Go to Step 11
10Install the illumination relay in its original position,
and install a new headlamp relay.
Is the repair complete?–System OK–
111. With the headlamp relay removed, turn the
headlamp switch to the low–beam position.
2. Use an ohmmeter to check the continuity be-
tween the connector for relay terminal 85 and
ground.
Does the ohmmeter indicate the specified value?
0 WGo to Step 17Go to Step 12

LIGHTING SYSTEMS 9B – 19
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
121. Reinstall the headlamp relay.
2. Check the voltage at the light switch connector
terminal 2.
Does the voltage equal the specified value?11–14 vGo to Step 14Go to Step 13
13Repair the open circuit between headlamp relay ter-
minal 85 and the light switch connector terminal 2.
Is the repair complete?–System OK–
141. Disconnect the light switch connector.
2. Turn the headlamps to the low–beam position.
3. Use an ohmmeter to check the continuity be-
tween terminals 2 and 3 of light switch.
Does the ohmmeter indicate the specified value?
0 WGo to Step 16Go to Step 15
15Replace the light switch.
Is the repair complete?–System OK–
16Repair the open circuit between terminal 3 of light
switch connector and ground.
Is the repair complete?–System OK–
17Check the voltage at headlamp switch connector
terminal 6.
Does the voltage equal the specified value?11–14 vGo to Step 19Go to Step 18
18Repair the open circuit between headlamp switch
connector and terminal 87 of the headlamp relay.
Is the repair complete?–System OK–
191. Disconnect headlamp switch connector.
2. Turn the headlamps to the low–beam position.
3. Connect an ohmmeter between terminals 5
and 6 of headlamp switch connector. Observe
the reading on the ohmmeter.
4. Turn the headlamps to the high–beam position.
5. Connect an ohmmeter between terminals 4
and 6 of the headlamp switch. Observe the
reading on the ohmmeter.
Does the ohmmeter show the specified value for
both of the tests?
0 WGo to Step 20Go to Step 15
20Repair the open circuit between the headlamp
switch and fuses Ef20, Ef27 and Ef15.
Is the repair complete?–System OK–