2004 DAEWOO LACETTI Iat

4A – 2IHYDRAULIC BRAKES
DAEWOO V–121 BL4
SPECIFICATIONS
GENERAL SPECIFCATIONS
1.4/1.6/1.8/2.0 DOHC Engine
ApplicationMillimetersInches
Brake Drums:
Inside Diameter
Maximum Rebore Diameter
Out–of–Round200.00
201.00
0.047.87
7.91
0.0016
Front Brake Rotors:
Discard Thickness
Lateral Runout (Installed)
Rotor Diameter
Rotor Thickness (New)
Thickness Variation22.00
0.030
256
24.00
0.010.87
0.001
10.07
0.95
0.0004
Rear Brake Rotors:
Discard Thickness
Lateral Runout (Installed)
Rotor Diameter
Rotor Thickness (New)
Thickness Variation8
0.030
258
10.4
0.010.31
0.001
10.15
0.40
0.0004
Master Cylinder:
Bore Diameter (Nominal)
Bore Diameter (Maximum)22.22
22.290.875
0.878
Caliper:
Minimum Piston Diameter (Front)
Minimum Piston Diameter (Rear)54.00
322.126
1.260
Wheel Cylinder Diameter:
Maximum
Nominal20.7
20.640.815
0.812
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Bleeder Screw8–71
Brake Lines1612–
Brake Pedal–to–Pedal Bracket Hex Nut1813–
Front Disc Brake Hose–to–Caliper Bolt4030–
Rear Disc Brake Hose–to–Caliper Bol3224–

4A – 12IHYDRAULIC BRAKES
DAEWOO V–121 BL4
12. Slowly push and hold the brake pedal one time.
13. Remove the bleeder valve dust cover and loosen
the bleeder screw to purge the air from the cylinder.
14. Tighten the bleeder screw.
Tighten
Tighten the bleeder screw to 8 NSm (71 lb–in).
15. Slowly release the brake pedal. Wait 15 seconds
before proceeding with the next step.
Important : Rapid pumping of the brake pedal pushes the
master cylinder secondary piston down the bore in a man-
ner that makes it difficult to bleed the system.
16. Repeat the sequence, including the 15–second
wait, until all the air is removed. It may be neces-
sary to repeat the sequence 10 or more times to
remove all the air.
17. Locate the front bleeder caps.
18. Proceed to bleed the front brakes following the ap-
propriate sequence, beginning with step 12.
19. Check the brake pedal for sponginess. Repeat the
entire bleeding procedure to correct this condition.
20. Replace the bleeder valve dust cover.
PRESSURE BLEEDING THE BRAKES
Notice : Pressure bleeding equipment must be of the dia-
phragm type. It must have a rubber diaphragm between
the air supply and the brake fluid to prevent air, moisture,
oil, and other contaminants from entering the hydraulic
system. Contamination could lead to deterioration of the
braking components and loss of braking action.
1. Disconnect the master cylinder electrical connector.
2. Remove the master cylinder reservoir cap.
3. Connect the bleeder with the adapter to the master
cylinder reservoir.
4. For vehicles with the antilock braking system
(ABS), locate and remove the hydraulic modulator
bleeder valves. Refer to Section 4F, Antilock Brake
System.
5. Charge the bleeder ball to 140 to 172 kPa (20 to 25
psi).
6. Connect the line to the adapter. Open the line
valve.
7. Raise and suitably support the vehicle.
Important : The bleeding sequence is as follows: right
rear, left front, left rear and right front.

SECTION : 4D
FRONT DISC BRAKES
TABLE OF CONTENTS
SPECIFICATIONS4D–1 . . . . . . . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specirications 4D–1. . . . . . . . . .
DIAGNOSIS4D–1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lining Inspection 4D–1. . . . . . . . . . . . . . . . . . . . . . . . . .
Rotor Inspection 4D–1. . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE AND REPAIR4D–3 . . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 4D–3. . . . . . . . . . . . . . . . . . . . .
Shoe and Lining 4D–3. . . . . . . . . . . . . . . . . . . . . . . . . . Caliper Assembly 4D–3. . . . . . . . . . . . . . . . . . . . . . . . . .
Rotor 4D–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Splash Shield 4D–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR 4D–6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Caliper Overhaul 4D–6. . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION4D–9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disc Brake Caliper Assembly 4D–9. . . . . . . . . . . . . . . .
SPECIFICATIONS
FASTENER TIGHTENING SPECIRICATIONS
ApplicationNSmLb–FtLb–In
Brake Hose Inlet Fitting–to–Caliper Bolt4030–
Caliper Bleeder Valve8–71
Caliper–to–Steering Knuckle Mounting Bolts9570–
Retaining Frame–to–Caliper Housing Bolts2720–
Rotor–to–Front Wheel Hub Detent Screw4–35
Splash Shield–to–Steering Knuckle Screws4–35
DIAGNOSIS
LINING INSPECTION
1. Raise and suitably support the vehicle.
2. Remove the front wheels. Refer to Section 2E,
Tires and Wheels.
3. Visually check the linings for minimum thickness
and wear.
4. Measure the thickness.
Important : The minimum thickness of the inner or the
outer pad is 7 mm (0.28 inch).
5. Install the brake pads in axle sets only.
6. Install the front wheels. Refer to Section 2E, Tires
and Wheels.
7. Lower the vehicle.ROTOR INSPECTION
Thickness variation can be checked by measuring the
thickness of the rotor at four or more points around the cir-
cumference of the rotor. All measurements must be made
at the same distance in from the edge of the rotor.
A rotor that varies by more than 0.01 mm (0.0004 inch) can
cause pedal pulsations and/or front end vibration during
brake applications. A rotor that does not meet these speci-
fications should be refinished to specifications or re-
placed.

SECTION : 4E1
REAR DISC BRAKES
TABLE OF CONTENTS
SPECIFICATIONS4E1–1 . . . . . . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 4E1–1. . . . . . . . . .
DIAGNOSIS4E1–1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lining Inspection 4E1–1. . . . . . . . . . . . . . . . . . . . . . . . .
Rotor Inspection 4E1–1. . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE AND REPAIR4E1–3 . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 4E1–3. . . . . . . . . . . . . . . . . . . .
Shoe and Lining 4E1–3. . . . . . . . . . . . . . . . . . . . . . . . . . Caliper 4E1–4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rotor 4E1–5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hub and Parking Brake Shoe/Backplate 4E1–6. . . . .
UNIT REPAIR 4E1–10. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Caliper Overhaul 4E1–10. . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION4E1–12 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disc Brake Caliper Assembly 4E1–12. . . . . . . . . . . . . .
SPECIFICATIONS
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Brake Hose Inlet Bolt and Ring Seals3224–
Caliper Mounting Bolts5641–
Lower Caliper Mounting Bolt2720–
Parking Brake Shoe Hold–Down Spring As-
sembly Screw4–35
Rotor Detent Screw4–35
Hub Bolts6548–
DIAGNOSIS
LINING INSPECTION
1. Raise and suitably support the vehicle.
2. Remove the rear wheels. Refer to Section 2E, Tires
and Wheels.
3. Visually check the brake shoe linings for minimum
thickness and wear.
4. Measure the thickness.
Important : The minimum discard thickness of the brake
shoe lining is 2 mm (0.08 inch).
5. Install the shoes in axle sets only.
6. Install the rear wheels. Refer to Section 2E, Tires
and Wheels.
7. Lower the vehicle.
ROTOR INSPECTION
Brake rotors are manufactured with close tolerances for
thickness variation, flatness, and lateral runout, but pits
and grooves are created in rotors during usage. Lack of
uniformity of the braking surfaces of the rotor can cause
inadequate braking and a pulsating pedal during braking.
The surface finish of the rotor is also important because
an unsuitable surface finish can cause pulling and rapid
wear of the brake shoe lining. If a rotor does not meet the
specification, it should be refinished to specification or re-
placed. Refinishing of the rotor should only be done with
precision equipment.
Thickness variation can be checked by measuring the
thickness of the rotor at four or more points around the cir-
cumference of the rotor. All measurements must be made
at the same distance from the edge of the rotor. A rotor that
varies by more than. 1.0 mm (0.04 inch) can cause pedal

4F – 50IANTILOCK BRAKE SYSTEM
DAEWOO V–121 BL4
J3B14F11
Left Front Left RearRight Front
Right Rear
EBCM
BRN LT
BLU1
2
6
7
PPL
GRYGRY GRY
YEL
C111
WHT 1
12
2
44
55WHT WHT1
1 2
43
89
Wheel Speed Sensors
BRNBRN DK
BLUBLK
BLK REDC302
C110 WHT
WHT1 2
2
110
33
DIAGNOSTIC TROUBLE CODE (DTC) C0245
WHEEL SPEED SENSOR FREQUENCY ERROR
Circuit Description
The toothed wheel generates a voltage pulse as it moves
past the wheel speed sensor. Each tooth–gap–tooth se-
ries on the wheel generates the pulses. The electronic
brake control module (EBCM) uses the frequency of these
pulses to determine wheel speed. The voltage generated
depends on the air gap between the wheel speed sensor
and the toothed wheel, and on the wheel speed.
Diagnosis
This DTC will set when the EBCM cannot identify which
wheel speed sensor is causing the malfunction. It is nec-
essary to check all wheel speed sensors and associated
wiring to determine the cause of the DTC.
Cause(s)
S Incorrect number of teeth on the toothed wheel.
S Damaged or broken teeth on the toothed wheel.
S Discontinuity or short in wheel speed sensor wiring.
Fail Action
Antilock brake system (ABS) action is disabled and the
ABS warning lamp is ON.Test Description
The number(s) below refer to step(s) on the diagnostic
table.
1. This step begins the examination of the front wheel
speed sensors.
3. This step checks for a problem with one of the front
toothed rings.
5. This step checks the front wheel speed sensors.
7. This step checks for shorts in a front wheel speed
sensor harness.
9. This step checks for opens in a front wheel speed
sensor harness.
11. This step begins a check of the rear wheel speed
sensors.
13. This step checks for a problem with one of the rear
toothed rings.
15. This step checks the rear wheel speed sensors.
17. This step checks for shorts in a rear wheel speed
sensor harness.
19. This step checks for opens in a rear wheel speed
sensor harness.

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 – 63
DAEWOO V–121 BL4
FRONT WHEEL SPEED SENSOR
JUMPER HARNESS
(Left–Hand Drive Shown, Right–Hand Drive
Similar)
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect connector from the EBCM.
3. Remove the appropriate terminals from connector:
S Right–side – terminals 4 (WHT) and 5 (GRY).
S Left–side – terminals 6 (BRN) and 7 (LT BLU).
4. Both speed sensor harnesses break out of the ABS
wiring harness just beyond the ABS connector. The
right–side speed sensor harness crosses the top of
the fire wall to the right–side fender area. The left–
side speed sensor harness goes directly to the left–
side fender area.
5. Free the speed sensor harness from the wiring har-
ness.
6. Remove the front wheel speed sensor electrical
connector from the retaining clamps and disconnect
the harness from the sensor connector.
Installation Procedure
1. Install the front wheel speed sensor jumper har-
ness.
2. Connect the front wheel speed sensor electrical
connector and secure it into the clamps.
3. Replace the jumper harness into the wiring har-
ness.
4. Insert the terminals into connector as they had
been removed:
S Right–side – terminals 4 (WHT) and 5 (GRY).
S Left–side – terminals 6 (BRN) and 7 (LT BLU).
5. Connect EBCM connector.
6. Connect the negative battery cable.

SECTION 5
ELECTRICAL WIRING DIAGRAMS
CONTENTS
1. STARTING & CHARGING SYSTEM5–8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1) BATTERY, IGNITION SWITCH, STARTER MOTOR, GENERATOR & PNP SWITCH CIRCUIT 5–8. . . . . . . . . .
2. ECM (ENGINE CONTROL MODULE) : MR–140 5–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1) BATTERY POWER SUPPLY, GROUND, EI SYSTEM & CKP SENSOR CIRCUIT 5–10. . . . . . . . . . . . . . . . . . . . .
2) FUEL PUMP, INJECTOR & HEATED O2 SENSOR CIRCUIT 5–12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3) IAC, SENSOR(MAP, ECT, TP, KNOCK, ACP & ROUGH ROAD) & LEGR CIRCUIT 5–14. . . . . . . . . . . . . . . . . . .
4) EVAP CANISTER PURGE SOLENOID, CMP SENSOR, CLUSTER & VSS CIRCUIT 5–16. . . . . . . . . . . . . . . . .
5) CLUSTER, FUEL PUMP & TCM CIRCUIT 5–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6) DLC, MIL LAMP & IMMOBILIZER CONTROL CIRCUIT 5–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3. ECM (ENGINE CONTROL MODULE) : HV–240 5–22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1) BATTERY POWER SUPPLY, GROUND, EI SYSTEM & CKP SENSOR CIRCUIT 5–22. . . . . . . . . . . . . . . . . . . . .
2) FUEL PUMP, INJECTOR & O2 SENSOR CIRCUIT 5–24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3) IAC, SENSOR(MAP, ECT, TP, IAT, KNOCK & ACP) & EGR VALVE CIRCUIT 5–26. . . . . . . . . . . . . . . . . . . . . . . .
4) EVAP CANISTER PURGE SOLENOID, CMP SENSOR, CLUSTER & VSS CIRCUIT 5–28. . . . . . . . . . . . . . . . .
5) CLUSTER, FUEL PUMP & TCM CIRCUIT 5–30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6) DLC, MIL LAMP, IMMOBILIZER CONTROL & RON SWITCH CIRCUIT 5–32. . . . . . . . . . . . . . . . . . . . . . . . . . . . .