2004 DAEWOO LACETTI sensor

ANTILOCK BRAKE SYSTEM 4F – 33
DAEWOO V–121 BL4
DTC C0050 – Right Rear Wheel Speed Sensor Circuit Malfunction
StepActionValue(s)YesNo
1Examine the wheel speed sensor.
Are there any signs of physical damage?–Go to Step 3Go to Step 2
21. Turn the ignition switch to LOCK.
2. Disconnect the left rear wheel speed sensor
connector.
3. Use a digital voltmeter (DVM) to measure the
resistance between the sensor terminals.
Is the resistance within the specified value at
approximately 25°C (77°F)?1280–1920 WGo to Step 4Go to Step 3
3Replace the wheel speed sensor.
Is the repair complete?–System OK–
41. Switch the DVM to the AC millivolt range.
2. Measure the voltage output of between the
wheel speed sensor terminals while rotating
the wheel about 1 revolution every 2 seconds.
Is the output within the specified value?
120 vGo to Step 6Go to Step 5
5Replace the speed sensor or the toothed wheel as
required.
Is the repair complete?–System OK–
61. Disconnect the harness from the EBCM.
2. Connect a DVM between ground and one ter-
minal of the wheel speed connector.
3. Turn the ignition to ON.
4. Repeat the above test for the other terminal of
the wheel speed connector.
Is the voltage for either of these terminals within the
specified value?> 1 vGo to Step 7Go to Step 8
7Repair the short to voltage in the affected circuit.
Is the repair complete?–System OK–
81. Turn the ignition switch to LOCK.
2. Measure the resistance to ground from termi-
nal 1 at the harness EBCM connector.
3. Measure the resistance to ground from termi-
nal 2 at the harness EBCM connector.
Is the resistance at either circuit less than the speci-
fied value?Go to Step 9Go to Step 10
9Repair the short to ground in the affected circuit.
Is the repair complete?–System OK–
101. Measure the resistance between terminal 1 at
the harness EBCM connector and the harness
wheel speed sensor connector terminal con-
nected to the WHT wire.
2. Measure the resistance between terminal 2 at
the harness EBCM connector and the harness
wheel speed sensor connector terminal con-
nected to the GRY wire.
Is the resistance on either circuit within the specified
value?> 5 WGo to Step 11Go to Step 12

ANTILOCK BRAKE SYSTEM 4F – 47
DAEWOO V–121 BL4
J3B14F10
EBCM
ORN/
BLK
LT BLULT B L U
BLK/ WHT
C201 C202
141
40
19
61
G1062
4
15A Ef13
6
C10211
S30114
C201C110
76
C202 11
DIAGNOSTIC TROUBLE CODE (DTC) C0161
ABS BRAKE SWITCH CIRCUIT MALFUNCTION
Circuit Description
When the brake pedal is depressed, the contacts on the
brake light switch close to illuminate the brake lights. Bat-
tery voltage is also applied to terminal 14 of the electronic
brake control module (EBCM), which signals the ABS con-
troller that the brakes are applied and ABS may be need-
ed. Without this, signals from a wheel speed sensor that
may indicate need for ABS intervention are questionable.
When the brake pedal is not depressed, the EBCM termi-
nal 14 is grounded through the brake lights.
Diagnosis
This procedure will check whether there is no output or
constant output from the brake light switch and will deter-
mine the cause as a faulty switch or a problem in the cir-
cuitry.
Cause(s)
S The ground connection or the positive connection at
the EBCM has failed.
S There is an open, short to ground, or short to posi-
tive in the vehicle wiring.S The brake light switch has failed.
Fail Action
The system records a DTC C0161. ABS and EBD opera-
tion is enabled and ABS / EBD warning lamp don’t turn on.
Test Description
The number(s) below refer to step(s) on the diagnostic
table.
1. This simple test will isolate the problem to the fuse–
brake light switch–splice 301 area or the splice
301–EBCM area.
3. This is the first step in identifying an open, a short
to ground, a short to voltage, or a faulty brake light
switch.
11. This step begins the process of finding an open, a
defective connector, or a faulty EBCM.
Diagnostic Aids
Inspect wiring and connectors carefully and thoroughly.
Failure to do so could result in misdiagnosis, causing part
replacement with reappearance of the malfunction.

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.

ANTILOCK BRAKE SYSTEM 4F – 51
DAEWOO V–121 BL4
Diagnostic Aids
DTC C0245 may be set by running the scan tool auto test
if the throttle angle readings are not updating while in the
data list mode. If this is the case, clear the DTCs, discon-
nect the scan tool, and road test the vehicle to at least 12
km/h (7 mph) to see if the DTC resets.
Check the toothed wheels for any large grooves, gouges,
marks, etc. that might influence the tooth’s signal at the
wheel speed sensor. Also check for a buildup of foreignmaterial in the gaps between teeth in the toothed wheel,
this material may cause this malfunction.
A badly worn hub/bearing assembly may cause this mal-
function. The wheel speed sensor–to–toothed wheel air
gap may change excessively due to bearing play.
If an improper rear hub assembly or front outer constant
velocity joint is installed, one with a toothed wheel contain-
ing the incorrect number of teeth, this DTC can set. Be
sure that the front and the rear toothed wheel have 47 and
29 teeth.
DTC C0245 – Wheel Speed Sensor Frequency Error
StepActionValue(s)YesNo
1Visually inspect the wiring for the front wheel speed
sensors.
Is there any damage?–Go to Step 2Go to Step 3
2Check that the correct outer constant velocity (CV)
joints are installed on the vehicle. The front speed
rings have 47 teeth and the rear speed rings have 29
theeth.
Is the repair complete?–System OK–
3Check fuse EF2 in the engine fuse block.
Is one of these incorrect?–Go to Step 4Go to Step 5
4Replace the incorrect outer CV joint with the proper
unit.
Is the repair complete?–System OK–
51. Disconnect the wheel speed sensor harnesses
from the wheel speed sensor connectors.
2. Measure the wheel speed sensor resistance at
the wheel speed sensor connector terminals.
Does the resistance fall within the specified values
for both wheel speed sensors?1280–1920 WGo to Step 7Go to Step 6
6Replace the faulty wheel speed sensor.
Is the repair complete?–System OK–
71. Disconnect ABS control module connector.
2. Check each wheel speed sensor harness for a
short circuit between its wires with a digital
ohmmeter attached to the two terminals at the
harness side of the wheel speed sensor con-
nector.
3. Also check each wheel speed sensor harness
wire for a short to ground from the connector
terminals.
Is there any short circuit in either wheel speed sen-
sor harness?–Go to Step 8Go to Step 9
8Repair the short circuit in the wiring or from a wiring
harness to ground.
Is the repair complete?–System OK–

4F – 52IANTILOCK BRAKE SYSTEM
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
9Check the continuity of the wiring in both front wheel
speed sensor circuits between the ABS connector
and the wheel speed sensor wheel speed sensor
connector on each side of the vehicle.
1. The left side uses terminals 6 and 7 at the ABS
connector.
2. The right side uses terminals 4 and 5 at the
ABS connector.
Is continuity good for both harnesses?–Go to Step 11Go to Step 10
10Repair the discontinuity found in the front wheel
speed sensor harness.
Is the repair complete?–System OK–
111. Visually inspect the wiring for the rear wheel
speed sensors.
2. Check that the wheel speed sensors are prop-
erly mounted and that the retaining bolts are
properly tightened.
Is there any damage?–Go to Step 12Go to Step 13
12Repair or replace components as required.
Is the repair complete?–System OK–
13Remove each wheel speed sensor from the rear
knuckles and inspect the toothed ring through the
wheel speed sensor mounting holes.
1. Check for any damaged or missing teeth.
2. Check that the ring is properly positioned under
the wheel speed sensor.
Is there any damage or other fault with either speed
ring?–Go to Step 14Go to Step 15
14Replace the rear wheel hub with the proper unit.
Is the repair complete?–System OK–
151. Disconnect the rear wheel speed sensor har-
nesses from the wheel speed sensor connec-
tors.
2. Measure the wheel speed sensor resistance at
the wheel speed sensor connector terminals.
Does the resistance fall within the specified values
for both wheel speed sensors?1280–1920 WGo to Step 17Go to Step 16
16Replace the faulty wheel speed sensor.
Is the repair complete?–System OK–
171. The ABS control module connector should still
be disconnected. Disconnect it now if it is not.
2. Check each wheel speed sensor harness for a
short circuit between its wires with a digital
ohmmeter attached to the two terminals at the
harness side of the wheel speed sensor con-
nector.
3. Also check each wheel speed sensor harness
wire for a short to ground from the connector
terminals.
Is there any short circuit in either wheel speed sen-
sor harness?–Go to Step 18Go to Step 19

ANTILOCK BRAKE SYSTEM 4F – 53
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
18Repair the short circuit in the wiring or from a wire to
ground.
Is the repair complete?–System OK–
19Check the continuity of the wiring in both rear wheel
speed sensor circuits between the ABS connector
and the wheel speed sensor wheel speed sensor
connector on each side of the vehicle.
1. The left side uses terminals 8 and 9 at the ABS
connector.
2. The right side uses terminals 1 and 3 at the
ABS connector.
Is continuity good for both harnesses?–Go to Step 21Go to Step 20
20Repair the discontinuity found in the rear wheel
speed sensor wheel speed sensor harness or con-
nector C110.
Is the repair complete?–System OK–
21Replace the ABS unit.
Is the repair complete?–System OK–

4F – 62IANTILOCK BRAKE SYSTEM
DAEWOO V–121 BL4
FRONT WHEEL SPEED SENSOR
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the front wheel speed sensor electrical
connector.
3. Raise and suitably support the vehicle.
4. Remove the wheel. Refer to Section 2E, Tires and
Wheels.
5. Turn the steering wheel to expose the speed sen-
sor. It is located at the rear of the steering knuckle
near the tie rod end.
6. Remove the bolt and the front wheel speed sensor
from the steering knuckle.
7. Free the feedthrough grommet for the speed sen-
sor harness and the hydraulic pipe from the strut
tower. Remove the speed sensor harness from it so
that the connector can pass through the hole in the
strut tower.
8. Free the sensor harness from the grommet holders
and the clamps and pull it through the fender.
Installation Procedure
1. Install the front wheel speed sensor to the steering
knuckle. Secure it with the bolt.
Tighten
Tighten the front wheel speed sensor bolt to 8 NSm
(71 lb–in).
2. Feed the sensor harness into the engine compart-
ment, insert it into the grommet, and secure the
grommet into the hole in the strut tower.
3. Secure the harness into the grommet holders and
the clamps under the fender.
4. Install the wheel. Refer to Section 2E, Tires and
Wheels.
5. Lower the vehicle.
6. Connect the front wheel speed sensor electrical
connector.
7. Connect the negative battery cable.

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.