4F – 26IANTILOCK BRAKE SYSTEM
DAEWOO V–121 BL4
J3B14F06
Right Front
Wheel Speed
Sensor
EBCM
PPL
GRYYEL
C111
WHT 1
12
2
4 5
DIAGNOSTIC TROUBLE CODE (DTC) C0040
RIGHT FRONT WHEEL SPEED SENSOR CIRCUIT
MALFUNCTION
Circuit Description
The toothed wheel generates a voltage pulse as it moves
past the sensor. Each tooth–gap–tooth series on the
wheel generates the pulses. The electronic brake control
module (EBCM) uses the frequency of these pulses to de-
termine the wheel speed. The voltage generated depends
on the air gap between the sensor and the toothed wheel,
and on the wheel speed.
Diagnosis
This procedure checks for a malfunctioning wheel speed
sensor, a short to ground or to voltage in the wiring, or a
contact problem in a connector.
Cause(s)
S The wheel speed sensor is defective or discon-
nected.
S There is a problem in the wiring.
S There is a problem with a connector.
S There is a problem in the toothed ring.
S Wrong installed WSS.
S Wrong sensor signal.
S Signal noise via WSS.
Fail Action
ABS action is disabled, and the ABS warning lamp is ON.
EBD is enabled. (Refer to the EBD failure matrix in this
section)
Test Description
The number(s) below refer to step(s) on the diagnostic
table.1. This step begins an examination for a defective
wheel speed sensor.
6. This step tests the wiring for a short to voltage.
8. This step tests the wiring for a short to ground.
10. This step tests for an open or high resistance in the
wiring.
Diagnostic Aids
Be sure that the speed sensor wiring is properly routed and
retained. This will help to prevent false signals due to the
pickup of electrical noise.
It is very important to perform a thorough inspection of the
wiring and the connectors. Failure to inspect the wiring
and the connectors carefully and completely may result in
misdiagnosis, causing part replacement with the reap-
pearance of the malfunction.
You can use the scan tool to monitor wheel speeds during
a road test. Watch the wheel speeds being displayed on
the scan tool to see if any of the readings is unusual, such
as one sensor varying in speed from the other three, a sig-
nal going intermittently high or low, etc. If this does not
identify the intermittent, wet the speed sensor harness on
the underside of the vehicle and perform a road test, moni-
toring the wheel speeds with the scan tool.
Important : If the WSS signal fault input to the EBCM, the
ABS warning lamp turns on. As if a sensor signal fault can
be removed by the scan tool, the ABS warning lamp
doesn’t turn off. In order to turn ABS warning lamp off, you
should drive a car up to 12 km/h.
ANTILOCK BRAKE SYSTEM 4F – 27
DAEWOO V–121 BL4
DTC C0040 – Right Front 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 right front 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 4 at the harness EBCM connector.
3. Measure the resistance to ground from termi-
nal 5 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 4 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 5 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 – 29
DAEWOO V–121 BL4
J3B14F07
Left Rear
Wheel Speed
Sensor EBCM
RED
DK BLUBLK
GRYBLK
C302 C110
WHT5 8
14 9
43
2
DIAGNOSTIC TROUBLE CODE (DTC) C0045
LEFT REAR WHEEL SPEED SENSOR CIRCUIT
MALFUNCTION
Circuit Description
The toothed wheel generates a voltage pulse as it moves
past the sensor. Each tooth–gap–tooth series on the
wheel generates the pulses. The electronic brake control
module (EBCM) uses the frequency of these pulses to de-
termine the wheel speed. The voltage generated depends
on the air gap between the sensor and the toothed wheel,
and on the wheel speed.
Diagnosis
This procedure checks for a malfunctioning wheel speed
sensor, a short to ground or to voltage in the wiring, or a
contact problem in a connector.
Cause(s)
S The wheel speed sensor is defective or discon-
nected.
S There is a problem in the wiring.
S There is a problem with a connector.
S There is a problem in the toothed ring.
S Wrong installed WSS.
S Wrong sensor signal.
S Signal noise via WSS.
Fail Action
ABS action is disabled, and the ABS warning lamp is ON.
EBD is enabled. (Refer to the EBD failure matrix in this
section)
Test Description
The number(s) below refer to step(s) on the diagnostic
table.1. This step begins an examination for a defective
wheel speed sensor.
6. This step tests the wiring for a short to voltage.
8. This step tests the wiring for a short to ground.
10. This step tests for an open or a high resistance in
the wiring.
Diagnostic Aids
Be sure that the speed sensor wiring is properly routed and
retained. This will help to prevent false signals due to the
pickup of electrical noise.
It is very important to perform a thorough inspection of the
wiring and the connectors. Failure to inspect the wiring
and the connectors carefully and completely may result in
misdiagnosis, causing part replacement with the reap-
pearance of the malfunction.
You can use the scan tool to monitor wheel speeds during
a road test. Watch the wheel speeds being displayed on
the scan tool to see if any of the readings is unusual, such
as one sensor varying in speed from the other three, a sig-
nal going intermittently high or low, etc. If this does not
identify the intermittent, wet the speed sensor harness on
the underside of the vehicle and perform a road test, moni-
toring wheel speeds with the scan tool.
Important : If the WSS signal fault input to the EBCM, the
ABS warning lamp turns on. As if a sensor signal fault can
be removed by the scan tool, the ABS warning lamp
doesn’t turn off. In order to turn ABS warning lamp off, you
should drive a car up to 12 km/h.
4F – 30IANTILOCK BRAKE SYSTEM
DAEWOO V–121 BL4
DTC C0045 – Left 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 8 at the harness EBCM connector.
3. Measure the resistance to ground from termi-
nal 9 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 8 at
the harness EBCM connector and the harness
wheel speed sensor connector terminal con-
nected to the RED wire.
2. Measure the resistance between terminal 9 at
the harness EBCM connector and the harness
wheel speed sensor connector terminal con-
nected to the BLK wire.
Is the resistance on either circuit within the specified
value?> 5 WGo to Step 11Go to Step 12
4F – 32IANTILOCK BRAKE SYSTEM
DAEWOO V–121 BL4
J3B14F08
Right Rear
Wheel Speed
Sensor EBCM
BRN
BRN
GRYC302 C110
WHT WHT
WHT1
110
1 3
3
2
2
DIAGNOSTIC TROUBLE CODE (DTC) C0050
RIGHT REAR WHEEL SPEED SENSOR CIRCUIT
MALFUNCTION
Circuit Description
The toothed wheel generates a voltage pulse as it moves
past the sensor. Each tooth–gap–tooth series on the
wheel generates the pulses. The electronic brake control
module (EBCM) uses the frequency of these pulses to de-
termine the wheel speed. The voltage generated depends
on the air gap between the sensor and the toothed wheel,
and on the wheel speed.
Diagnosis
This procedure checks for a malfunctioning wheel speed
sensor, a short to ground or to voltage in the wiring, or a
contact problem in a connector.
Cause(s)
S The wheel speed sensor is defective or discon-
nected.
S There is a problem in the wiring.
S There is a problem with a connector.
S There is a problem in the toothed ring.
S Wrong installed WSS.
S Wrong sensor signal.
S Signal noise via WSS.
Fail Action
ABS action is disabled, and the ABS warning lamp is ON.
EBD is enabled. (Refer to the EBD failure matrix in this
section)
Test Description
The number(s) below refer to step(s) on the diagnostic
table.1. This step begins an examination for a defective
wheel speed sensor.
6. This step tests the wiring for a short to voltage.
8. This step tests the wiring for a short to ground.
10. This step tests for an open or high resistance in the
wiring.
Diagnostic Aids
Be sure that the speed sensor wiring is properly routed and
retained. This will help to prevent false signals due to the
pickup of electrical noise.
It is very important to perform a thorough inspection of the
wiring and the connectors. Failure to inspect the wiring
and the connectors carefully and completely may result in
misdiagnosis, causing part replacement with the reap-
pearance of the malfunction.
You can use the scan tool to monitor wheel speeds during
a road test. Watch the wheel speeds being displayed on
the scan tool to see if any of the readings is unusual, such
as one sensor varying in speed from the other three, a sig-
nal going intermittently high or low, etc. If this does not
identify the intermittent, wet the speed sensor harness on
the underside of the vehicle and perform a road test, moni-
toring wheel speeds with the scan tool.
Important : If the WSS signal fault input to the EBCM, the
ABS warning lamp turns on. As if a sensor signal fault can
be removed by the scan tool, the ABS warning lamp
doesn’t turn off. In order to turn ABS warning lamp off, you
should drive a car up to 12 km/h.
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.