TSB-23-35-001

SUBJECT:
DIAGNOSTIC PROCEDURE CORRECTION FOR WHEEL
SPEED SENSOR CIRCUIT - SERVICE MANUAL REVISION
DATE:
TSB-23-35-001
January 2023
MODEL:
See below
No:
CIRCULATE TO:
[ ] GENERAL MANAGER
[ X ] PARTS MANAGER
[ X ] TECHNICIAN
[ X ] SERVICE ADVISOR
[ X ] SERVICE MANAGER
[ X ] WARRANTY PROCESSOR
[ ] SALES MANAGER
PURPOSE
This TSB provides correction for the Wheel Speed Sensor Circuit.
AFFECTED VEHICLES
• 2018-2020 and 2022-2023 Eclipse Cross
AFFECTED SERVICE MANUAL
• 2018-2020 and 2022-2023 Eclipse Cross Service Manual, Group 35-Service Brakes
PROCEDURE
Please use the chart below and replace the indicated pages of the affected Service Manual,
Group 35 - Service Brakes, Active Stability System (ASC), Diagnosis.
Applicable manual
Pub. No.
2018 ECLIPSE
CROSS Service
Manual
2019 ECLIPSE
CROSS Service
Manual
2020 ECLIPSE
CROSS Service
Manual
MSCD-020B-2018
2022 ECLIPSE
CROSS Service
Manual
2023 ECLIPSE
CROSS Service
Manual
MSCD-020B-2022
MSCD-020B-2019
Applicable title (SIE No.)
Contents
ACTIVE STABILITY CONTROL SYSTEM (ASC)
└DIAGNOSIS 
└DTC C100A FL Wheel Speed Sensor Circuit
DTC C1015 FR Wheel Speed Sensor Circuit DTC
C1020 RL Wheel Speed Sensor Circuit DTC
C102B RR Wheel Speed Sensor Circuit
Attached
sheet 1
MSCD-020B-2020
Attached
sheet 2
MSCD-020B-2023
Copyright 2023, Mitsubishi Motors North America, Inc.
The information contained in this bulletin is subject to change. For the latest version of this document, go to the
Mitsubishi Dealer Link, MEDIC, or the Mitsubishi Service Information website (www.mitsubishitechinfo.com).
1/6/2023
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(5244/MSB22M35502)
Attached sheet 1(1/14)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
DIAGNOSTIC TROUBLE CODE PROCEDURES
DTC C100A FL Wheel Speed Sensor Circuit
DTC C1015 FR Wheel Speed Sensor Circuit
DTC C1020 RL Wheel Speed Sensor Circuit
DTC C102B RR Wheel Speed Sensor Circuit
CAUTION
 If there is any problem in the CAN bus lines, an incorrect DTC may be set. Prior to this diagnosis, diagnose
the CAN bus lines (Refer to GROUP 54C − CAN Bus
Diagnostics Table).
 Whenever ECU is replaced, ensure that the CAN bus
lines are normal.
.
OPERATION
 The wheel speed sensor is a kind of a pulse generator. It
consists of encoders (a plate on which north and south pole
sides of the magnets are arranged alternately) for detecting
the wheel speed which rotates at the same speed of the
wheels and wheel speed sensors. This sensor outputs frequency pulse signals in proportion to the wheel speed.
 The pulse signals, which the wheel speed sensor creates,
are sent to ASC-ECU. ASC-ECU uses the frequency of the
pulse signals to determine the wheel speed.
.
DTC SET CONDITIONS
ASC-ECU monitors the voltage fluctuation in each wheel speed
sensor circuit. If ASC-ECU detects the open or short circuit in
the circuit, it will set a DTC.
.
PROBABLE CAUSES
Current trouble
 Damaged wiring harness and connectors
 Noise interference
 Malfunction of wheel speed sensor
 Malfunction of ASC-ECU
Past trouble
 Carry out diagnosis with particular emphasis on wiring harness and connector failures between ASC-ECU and the
wheel speed sensor. For diagnostic procedures, refer to
How to treat past trouble (GROUP 00 − How to Use Troubleshooting/How to Treat Past Trouble).
DIAGNOSIS
Required Special Tools:
 MB991223: Harness Set
 MB992006: Extra Fine Probe
1/6/2023
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Attached sheet 1(2/14)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 

STEP 1. Using scan tool (M.U.T.-IIISE), diagnose the CAN
bus line.
CAUTION
To prevent damage to scan tool (M.U.T.-IIISE), always turn
the ignition switch to the "LOCK" (OFF) position before
connecting or disconnecting scan tool (M.U.T.-IIISE).
(1) Connect scan tool (M.U.T.-IIISE). Refer to "How to connect
the Scan Tool (M.U.T.-IIISE)."
(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result normal?
YES : Go to Step 3.
NO : Repair the CAN bus lines (Refer to GROUP 54C 
CAN Bus Diagnostics Table). On
completion, go to Step 2.
STEP 2. DTC recheck after resetting CAN bus lines.
(1) Drive the vehicle at 20 km/h (12 mph) or higher.
NOTE: The ABS warning scan tool (M.U.T.-IIISE) does not
turn OFF in some cases unless the vehicle runs at 20 km/h
(12 mph) or higher.
(2) Turn the ignition switch from the ON position to the LOCK
(OFF) position.
Q: Is DTC C100A, 1015, 1020 or 102B set?
YES : Go to Step 3.
NO : This diagnosis is complete.
STEP 3.Using scan tool (M.U.T.-IIISE), check data list
Check the following data list.
 Item No.01: FL wheel speed sensor
 Item No.02: FR wheel speed sensor
 Item No.03: RL wheel speed sensor
 Item No.04: RR wheel speed sensor
Q: Is the check result normal?
YES : Go to Step 10.
NO : Go to Step 4.

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Attached sheet 5(7/14 to 14/14)
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Attached sheet 1(3/14)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 

STEP 4. Voltage measurement at the ASC-ECU connector
(FL+, FL-, FR+, FR-, RL+, RL-, RR+, RR- terminal).
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Turn the ignition switch to the "ON" position.
DTC C100A is set
 Measure the voltage between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body
ground.
OK: 1 V or less
DTC C1015 is set
 Measure the voltage between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body
ground.
OK: 1 V or less
DTC C1020 is set
 Measure the voltage between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body
ground.
OK: 1 V or less
DTC C102B is set
 Measure the voltage between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body
ground.
OK: 1 V or less
Q: Is the check result normal?
YES : Go to Step 5.
NO : Go to Step 6.
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Attached sheet 1(4/14)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 

STEP 5. Resistance measurement at ASC-ECU connector
(FL+, FL-, FR+, FR-, RL+, RL-, RR+, RR- terminal).
Disconnect the connector, and measure at the wiring harness
side.
DTC C100A is set
 Measure the resistance between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body ground.
OK: No continuity
DTC C1015 is set
 Measure the resistance between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body ground.
OK: No continuity
DTC C1020 is set
 Measure the resistance between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body ground.
OK: No continuity
DTC C102B is set
 Measure the resistance between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body ground.
OK: No continuity
Q: Is the check result normal?
YES : Go to Step 7.
NO : Go to Step 6.
STEP 6. Check the wiring harness between the ASC-ECU
connector terminal and the wheel speed sensor connector
terminal.
DTC C100A is set
 Check of short circuit in FL+, FL- line between ASC-ECU
connector and front wheel speed sensor (LH) connector.
DTC C1015 is set
 Check of short circuit in FR+, FR- line between ASC-ECU
connector and front wheel speed sensor (RH) connector.
DTC C1020 is set
 Check of short circuit in RL+, RL- line between ASC-ECU
connector and rear wheel speed sensor (LH) connector.
DTC C102B is set
 Check of short circuit in RR+, RR- line between ASC-ECU
connector and rear wheel speed sensor (LH) connector.
Q: Is the check result normal?
YES : Replace the wheel speed sensor.
NO : Repair the connector(s) or wiring harness.
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Attached sheet 1(5/14)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 

STEP 7. Voltage and current measurement at each wheel
speed sensors connector.
(1) Disconnect the wheel speed sensor connector, and
measure at the wiring harness side.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between the power supply terminal of
each wheel speed sensors and the body ground.
(4) Measure the output current at the special tool test harness
(MB991709) to connect between the wheel speed
sensor-side connector and the wiring harness connector.
OK:
 System voltage
 5  9 mA or 11  17 mA
Q: Is the check result normal?
YES : Go to Step 10.
NO : Go to Step 8.
STEP 8. Check the wiring harness between the ASC-ECU
connector terminal and the wheel speed sensor connector
terminal.
DTC C100A is set
 Check of open circuit in FL+, FL- line between ASC-ECU
connector and front wheel speed sensor (LH) connector.
DTC C1015 is set
 Check of open circuit in FR+, FR- line between ASC-ECU
connector and front wheel speed sensor (RH) connector.
DTC C1020 is set
 Check of open circuit in RL+, RL- line between ASC-ECU
connector and rear wheel speed sensor (LH) connector.
DTC C102B is set
 Check of open circuit in RR+, RR- line between ASC-ECU
connector and rear wheel speed sensor (RH) connector.
Q: Is the check result normal?
YES : Go to Step 9.
NO : Repair the connector(s) or wiring harness.
STEP 9. Check for wheel speed sensor as a single unit.
Q: Is the check result normal?
YES : Go to Step 10.
NO : Replace the wheel speed sensor.
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Attached sheet 1(6/14)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 

STEP 10. Check whether the DTC is set again.
(1) Erase the DTC.
(2) Drive the vehicle at 20 km/h (12 mph) or higher.
NOTE: The ABS warning light does not turn OFF in some
cases unless the vehicle runs at 20 km/h (12 mph) or
higher.
Q: Is DTC C100A, C1015, C1020 or C102B set?
YES : Replace the hydraulic unit (integrated with ASC-ECU).
NO : Intermittent malfunction (Refer to GROUP 00 − How
to Use Troubleshooting/How to Cope with Intermittent
Malfunctions).
DTC C1011 FL Wheel Speed Sensor Signal
DTC C101C FR Wheel Speed Sensor Signal
DTC C1027 RL Wheel Speed Sensor Signal
DTC C1032 RR Wheel Speed Sensor Signal
CAUTION
 If there is any problem in the CAN bus lines, an incorrect DTC may be set. Prior to this diagnosis, diagnose
the CAN bus lines (Refer to GROUP 54C − CAN Bus
Diagnostics Table).
 Whenever ECU is replaced, ensure that the CAN bus
lines are normal.
.
OPERATION
 The wheel speed sensor is a kind of a pulse generator. It
consists of encoders (a plate on which north and south pole
sides of the magnets are arranged alternately) for detecting
the wheel speed which rotates at the same speed of the
wheels and wheel speed sensors. This sensor outputs frequency pulse signals in proportion to the wheel speed.
 The pulse signals, which the wheel speed sensor creates,
are sent to ASC-ECU. ASC-ECU uses the frequency of the
pulse signals to determine the wheel speed.
.
DTC SET CONDITIONS
ASC-ECU monitors the signals from each wheel speed sensor
while the vehicle is being driven. If any fault below is found in
these sensor signals, ASC-ECU will set the relevant DTC.
 Irregular change in the wheel speed sensor signal
 Wheel speed sensor signal continuously indicates high
value.
.
PROBABLE CAUSES
1/6/2023
Current trouble
 Excessive gap between the wheel speed sensor and the
wheel speed detection encoder
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Attached sheet 1(7/14)
STEP 1. Voltage measurement at the ASC-ECU connector
(FL+, FL-, FR+, FR-, RL+, RL-, RR+, RR- terminal)
(1) Disconnect the ASC-ECU connector, and measure at the
wiring harness side.
(2) Turn the ignition switch to the "ON" position.
DTC C100A is set
• Measure the voltage between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body
ground.
OK: 1 volt or less
DTC C1015 is set
• Measure the voltage between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body
ground.
OK: 1 volt or less
DTC C1020 is set
• Measure the voltage between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body
ground.
OK: 1 volt or less
DTC C102B is set
• Measure the voltage between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body
ground.
OK: 1 volt or less
Q: Is the check result normal?
YES : Go to Step 3.
NO : Go to Step 2.
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STEP 2. Voltage measurement at the ASC-ECU connector.
(1) Disconnect the ASC-ECU connector and wheel speed
sensor connector, and measure at the wiring harness side
of the ASC-ECU connector.
(2) Turn the ignition switch to the "ON" position.
DTC C100A is set
• Measure the voltage between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body
ground.
OK: 1 volt or less
DTC C1015 is set
• Measure the voltage between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body
ground.
OK: 1 volt or less
DTC C1020 is set
• Measure the voltage between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body
ground.
OK: 1 volt or less
DTC C102B is set
• Measure the voltage between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body
ground.
OK: 1 volt or less
Q: Is the check result normal?
YES : Replace the wheel speed sensor.
NO : Repair the connector(s) or wiring harness.
1/6/2023
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Attached sheet 1(9/14)
STEP 3. Resistance measurement at ASC-ECU connector
(FL+, FL-, FR+, FR-, RL+, RL-, RR+, RR- terminal)
Disconnect the ASC-ECU connector, and measure at the wiring
harness side of the ASC-ECU connector.
DTC C100A is set
• Measure the resistance between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body ground.
OK: No continuity
DTC C1015 is set
• Measure the resistance between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body ground.
OK: No continuity
DTC C1020 is set
• Measure the resistance between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body ground.
OK: No continuity
DTC C102B is set
• Measure the resistance between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body ground.
OK: No continuity
Q: Is the check result normal?
YES : Go to Step 5.
NO : Go to Step 4.
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STEP 4. Resistance measurement at ASC-ECU connector.
Disconnect the ASC-ECU connector and wheel speed sensor
connector, and measure at the wiring harness side of the
ASC-ECU connector.
DTC C100A is set
• Measure the resistance between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body ground.
OK: No continuity
DTC C1015 is set
• Measure the resistance between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body ground.
OK: No continuity
DTC C1020 is set
• Measure the resistance between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body ground.
OK: No continuity
DTC C102B is set
• Measure the resistance between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body ground.
OK: No continuity
Q: Is the check result normal?
YES : Replace the wheel speed sensor.
NO : Repair the connector(s) or wiring harness.
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Attached sheet 1(11/14)
STEP 5. Resistance measurement at ASC-ECU connector.
Disconnect the ASC-ECU connector and wheel speed sensor
connector, and measure at the wiring harness side of the
ASC-ECU connector.
DTC C100A is set
• Measure the resistance between the ASC-ECU connector
(FL+ terminal) and (FL- terminal).
OK: No continuity
DTC C1015 is set
• Measure the resistance between the ASC-ECU connector
(FR+ terminal) and (FR- terminal).
OK: No continuity
DTC C1020 is set
• Measure the resistance between the ASC-ECU connector
(RL+ terminal) and (RL- terminal).
OK: No continuity
DTC C102B is set
• Measure the resistance between the ASC-ECU connector
(RR+ terminal) and (RR- terminal).
OK: No continuity
Q: Is the check result normal?
YES : Go to Step 6.
NO : Repair the connector(s) or wiring harness.
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STEP 6. Voltage measurement at the wheel speed sensor
connector.
(1) Disconnect the wheel speed sensor connector, and
measure at the wiring harness side.
(2) Turn the ignition switch to the "ON" position.
DTC C100A is set
• Measure the voltage between the wheel speed sensor
connector (FL+ terminal) and the body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage).
DTC C1015 is set
• Measure the voltage between the wheel speed sensor
connector (FR+ terminal) and the body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage).
DTC C1020 is set
• Measure the voltage between the wheel speed sensor
connector (RL+ terminal) and the body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage)
DTC C102B is set
• Measure the voltage between the wheel speed sensor
connector (RR+ terminal) and the body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage)
Q: Is the check result normal?
YES : Go to Step 8.
NO : Go to Step 7.
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Attached sheet 1(13/14)
STEP 7. Resistance measurement at ASC-ECU connector
and wheel speed sensor.
Disconnect the ASC-ECU connector and wheel speed sensor
connector, and measure at the wiring harness side of the
ASC-ECU connector and wheel speed sensor connector.
DTC C100A is set
• Check of open circuit in FL+ line between ASC-ECU connector and front wheel speed sensor (LH) connector.
OK: The resistance should be 2 ohms or less
DTC C1015 is set
• Check of open circuit in FR+ line between ASC-ECU connector and front wheel speed sensor (RH) connector.
OK: The resistance should be 2 ohms or less
DTC C1020 is set
• Check of open circuit in RL+ line between ASC-ECU connector and rear wheel speed sensor (LH) connector.
OK: The resistance should be 2 ohms or less
DTC C102B is set
• Check of open circuit in RR+ line between ASC-ECU connector and rear wheel speed sensor (RH) connector.
OK: The resistance should be 2 ohms or less
Q: Is the check result normal?
YES : Go to Step 11.
NO : Repair the connector(s) or wiring harness.
STEP 8. Current measurement at each wheel speed
sensors connector.
Refer to On-vehicle service - Wheel speed sensor
output current measurement.
Q: Is the check result normal?
YES : Go to Step 11.
NO : Go to Step 9.
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STEP 9. Resistance measurement at ASC-ECU connector
and wheel speed sensor.
Disconnect the ASC-ECU connector and wheel speed sensor
connector, and measure at the wiring harness side of the
ASC-ECU connector and wheel speed sensor connector.
DTC C100A is set
• Check of open circuit in FL- line between ASC-ECU connector and front wheel speed sensor (LH) connector.
OK: The resistance should be 2 ohms or less
DTC C1015 is set
• Check of open circuit in FR- line between ASC-ECU connector and front wheel speed sensor (RH) connector.
OK: The resistance should be 2 ohms or less
DTC C1020 is set
• Check of open circuit in RL- line between ASC-ECU connector and rear wheel speed sensor (LH) connector.
OK: The resistance should be 2 ohms or less
DTC C102B is set
• Check of open circuit in RR- line between ASC-ECU connector and rear wheel speed sensor (RH) connector.
OK: The resistance should be 2 ohms or less
Q: Is the check result normal?
YES : Go to Step 10.
NO : Repair the connector(s) or wiring harness.
STEP 10. Check for wheel speed sensor as a single unit.
Refer to Wheel speed sensor - Wheel speed sensor
inspection.
Q: Is the check result normal?
YES : Go to Step 11.
NO : Replace the wheel speed sensor.
STEP 11. Check whether the DTC is set again.
(1) Erase the DTC.
(2) Turn the ignition switch to the "LOCK" (OFF) position.
(3) Turn the ignition switch to the "ON" position.
(4) Drive the vehicle at 20 km/h (12 mph) or higher.
NOTE: The ABS warning light does not turn OFF in some
cases unless the vehicle runs at 20 km/h (12 mph) or
higher.
Q: Is DTC C100A, C1015, C1020 or C102B set?
YES : Replace the hydraulic unit (integrated with ASC-ECU).
NO : Intermittent malfunction (Refer to GROUP 00 - How to
Use Troubleshooting/How to Cope with Intermittent
Malfunctions).
1/6/2023
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Attached sheet 2(1/9)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
DIAGNOSTIC TROUBLE CODE PROCEDURES
DTC C100A FL Wheel Speed Sensor Circuit
DTC C1015 FR Wheel Speed Sensor Circuit
DTC C1020 RL Wheel Speed Sensor Circuit
DTC C102B RR Wheel Speed Sensor Circuit
CAUTION
• If there is any problem in the CAN bus lines, an incorrect DTC may be set. Prior to this diagnosis, diagnose
the CAN bus lines (Refer to GROUP 54C - CAN Bus
Diagnostics Table).
• Whenever ECU is replaced, ensure that the CAN bus
lines are normal.
OPERATION
• The wheel speed sensor is a kind of a pulse generator. It
consists of encoders (a plate on which north and south pole
sides of the magnets are arranged alternately) for detecting
the wheel speed which rotates at the same speed of the
wheels and wheel speed sensors. This sensor outputs frequency pulse signals in proportion to the wheel speed.
• The pulse signals, which the wheel speed sensor creates,
are sent to ASC-ECU. ASC-ECU uses the frequency of the
pulse signals to determine the wheel speed.
DTC SET CONDITIONS
ASC-ECU monitors the voltage fluctuation in each wheel speed
sensor circuit. If ASC-ECU detects the open or short circuit in
the circuit, it will set a DTC.
PROBABLE CAUSES
Current trouble
• Damaged wiring harness and connectors
• Noise interference
• Malfunction of wheel speed sensor
• Malfunction of ASC-ECU
Past trouble
• Carry out diagnosis with particular emphasis on wiring harness and connector failures between ASC-ECU and the
wheel speed sensor. For diagnostic procedures, refer to
How to treat past trouble (GROUP 00 - How to Use Troubleshooting/How to Treat Past Trouble).
1/6/2023
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Attached sheet 2(2/9)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
DIAGNOSIS
Required Special Tools:
• MB991223: Harness Set
STEP 1. Voltage measurement at the ASC-ECU connector
(FL+, FL-, FR+, FR-, RL+, RL-, RR+, RR- terminal)
(1) Disconnect the ASC-ECU connector, and measure at the
wiring harness side.
(2) Turn the ignition switch to the "ON" position.
DTC C100A is set
• Measure the voltage between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body
ground.
OK: 1 volt or less
DTC C1015 is set
• Measure the voltage between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body
ground.
OK: 1 volt or less
DTC C1020 is set
• Measure the voltage between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body
ground.
OK: 1 volt or less
DTC C102B is set
• Measure the voltage between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body
ground.
OK: 1 volt or less
Q: Is the check result normal?
YES : Go to Step 3.
NO : Go to Step 2.
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ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
STEP 2. Voltage measurement at the ASC-ECU connector.
(1) Disconnect the ASC-ECU connector and wheel speed
sensor connector, and measure at the wiring harness side
of the ASC-ECU connector.
(2) Turn the ignition switch to the "ON" position.
DTC C100A is set
• Measure the voltage between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body
ground.
OK: 1 volt or less
DTC C1015 is set
• Measure the voltage between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body
ground.
OK: 1 volt or less
DTC C1020 is set
• Measure the voltage between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body
ground.
OK: 1 volt or less
DTC C102B is set
• Measure the voltage between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body
ground.
OK: 1 volt or less
Q: Is the check result normal?
YES : Replace the wheel speed sensor.
NO : Repair the connector(s) or wiring harness.
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Attached sheet 2(4/9)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
STEP 3. Resistance measurement at ASC-ECU connector
(FL+, FL-, FR+, FR-, RL+, RL-, RR+, RR- terminal)
Disconnect the ASC-ECU connector, and measure at the wiring
harness side of the ASC-ECU connector.
DTC C100A is set
• Measure the resistance between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body ground.
OK: No continuity
DTC C1015 is set
• Measure the resistance between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body ground.
OK: No continuity
DTC C1020 is set
• Measure the resistance between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body ground.
OK: No continuity
DTC C102B is set
• Measure the resistance between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body ground.
OK: No continuity
Q: Is the check result normal?
YES : Go to Step 5.
NO : Go to Step 4.
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Attached sheet 2(5/9)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
STEP 4. Resistance measurement at ASC-ECU connector.
Disconnect the ASC-ECU connector and wheel speed sensor
connector, and measure at the wiring harness side of the
ASC-ECU connector.
DTC C100A is set
• Measure the resistance between the ASC-ECU connector
(FL+ terminal) and the body ground, and between the
ASC-ECU connector (FL- terminal) and the body ground.
OK: No continuity
DTC C1015 is set
• Measure the resistance between the ASC-ECU connector
(FR+ terminal) and the body ground, and between the
ASC-ECU connector (FR- terminal) and the body ground.
OK: No continuity
DTC C1020 is set
• Measure the resistance between the ASC-ECU connector
(RL+ terminal) and the body ground, and between the
ASC-ECU connector (RL- terminal) and the body ground.
OK: No continuity
DTC C102B is set
• Measure the resistance between the ASC-ECU connector
(RR+ terminal) and the body ground, and between the
ASC-ECU connector (RR- terminal) and the body ground.
OK: No continuity
Q: Is the check result normal?
YES : Replace the wheel speed sensor.
NO : Repair the connector(s) or wiring harness.
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Attached sheet 2(6/9)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
STEP 5. Resistance measurement at ASC-ECU connector.
Disconnect the ASC-ECU connector and wheel speed sensor
connector, and measure at the wiring harness side of the
ASC-ECU connector.
DTC C100A is set
• Measure the resistance between the ASC-ECU connector
(FL+ terminal) and (FL- terminal).
OK: No continuity
DTC C1015 is set
• Measure the resistance between the ASC-ECU connector
(FR+ terminal) and (FR- terminal).
OK: No continuity
DTC C1020 is set
• Measure the resistance between the ASC-ECU connector
(RL+ terminal) and (RL- terminal).
OK: No continuity
DTC C102B is set
• Measure the resistance between the ASC-ECU connector
(RR+ terminal) and (RR- terminal).
OK: No continuity
Q: Is the check result normal?
YES : Go to Step 6.
NO : Repair the connector(s) or wiring harness.
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Attached sheet 2(7/9)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
STEP 6. Voltage measurement at the wheel speed sensor
connector.
(1) Disconnect the wheel speed sensor connector, and
measure at the wiring harness side.
(2) Turn the ignition switch to the "ON" position.
DTC C100A is set
• Measure the voltage between the wheel speed sensor
connector (FL+ terminal) and the body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage).
DTC C1015 is set
• Measure the voltage between the wheel speed sensor
connector (FR+ terminal) and the body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage).
DTC C1020 is set
• Measure the voltage between the wheel speed sensor
connector (RL+ terminal) and the body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage)
DTC C102B is set
• Measure the voltage between the wheel speed sensor
connector (RR+ terminal) and the body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage)
Q: Is the check result normal?
YES : Go to Step 8.
NO : Go to Step 7.
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Attached sheet 6(8/9)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
STEP 7. Resistance measurement at ASC-ECU connector
and wheel speed sensor.
Disconnect the ASC-ECU connector and wheel speed sensor
connector, and measure at the wiring harness side of the
ASC-ECU connector and wheel speed sensor connector.
DTC C100A is set
• Check of open circuit in FL+ line between ASC-ECU connector and front wheel speed sensor (LH) connector.
OK: The resistance should be 2 ohms or less
DTC C1015 is set
• Check of open circuit in FR+ line between ASC-ECU connector and front wheel speed sensor (RH) connector.
OK: The resistance should be 2 ohms or less
DTC C1020 is set
• Check of open circuit in RL+ line between ASC-ECU connector and rear wheel speed sensor (LH) connector.
OK: The resistance should be 2 ohms or less
DTC C102B is set
• Check of open circuit in RR+ line between ASC-ECU connector and rear wheel speed sensor (RH) connector.
OK: The resistance should be 2 ohms or less
Q: Is the check result normal?
YES : Go to Step 11.
NO : Repair the connector(s) or wiring harness.
STEP 8. Current measurement at each wheel speed
sensors connector.
Refer to Wheel speed sensor - Wheel speed sensor
 inspection
Q: Is the check result normal?
YES : Go to Step 11.
NO : Go to Step 9.
 On-vehicle service - Wheel speed
sensor output current measurement
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Attached sheet 2(9/9)
ACTIVE STABILITY CONTROL SYSTEM (ASC)
DIAGNOSIS 
STEP 9. Resistance measurement at ASC-ECU connector
and wheel speed sensor.
Disconnect the ASC-ECU connector and wheel speed sensor
connector, and measure at the wiring harness side of the
ASC-ECU connector and wheel speed sensor connector.
DTC C100A is set
• Check of open circuit in FL- line between ASC-ECU connector and front wheel speed sensor (LH) connector.
OK: The resistance should be 2 ohms or less
DTC C1015 is set
• Check of open circuit in FR- line between ASC-ECU connector and front wheel speed sensor (RH) connector.
OK: The resistance should be 2 ohms or less
DTC C1020 is set
• Check of open circuit in RL- line between ASC-ECU connector and rear wheel speed sensor (LH) connector.
OK: The resistance should be 2 ohms or less
DTC C102B is set
• Check of open circuit in RR- line between ASC-ECU connector and rear wheel speed sensor (RH) connector.
OK: The resistance should be 2 ohms or less
Q: Is the check result normal?
YES : Go to Step 10.
NO : Repair the connector(s) or wiring harness.
STEP 10. Check for wheel speed sensor as a single unit.
Refer to .

Wheel speed sensor - Wheel speed sensor inspection
Q: Is the check result normal?
YES : Go to Step 11.
NO : Replace the wheel speed sensor.
STEP 11. Check whether the DTC is set again.
(1) Erase the DTC.
(2) Turn the ignition switch to the "LOCK" (OFF) position.
(3) Turn the ignition switch to the "ON" position.
(4) Drive the vehicle at 20 km/h (12 mph) or higher.
NOTE: The ABS warning light does not turn OFF in some
cases unless the vehicle runs at 20 km/h (12 mph) or
higher.
Q: Is DTC C100A, C1015, C1020 or C102B set?
YES : Replace the hydraulic unit (integrated with ASC-ECU).
NO : Intermittent malfunction (Refer to GROUP 00 - How to
Use Troubleshooting/How to Cope with Intermittent
Malfunctions).
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