Page 1307 of 1500

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-28
STEP 4. Retest the system
Q: Turn the ignition switch to the "ON" position. Do the
"TCL OFF" indicator light and the TCL work indicator
light illuminate for three seconds, and then go out after
the engine starts?
YES : The procedure is complete.
NO : . Return to Step 1.
INSPECTION PROCEDURE 5: When the TCL Switch is Pushed On, TCL does not Cancel.
NOTE: If the ABS-8 ECU or the active wheel
speed sensor are disconnected, or if the wiring is
an open/ short circuit, the ABS 8 ECU will shut
off power supply to the respective wheel speed
sensor. All other wheel speed sensors will oper-
ate normally. To restore the power supply, the
ignition switch must be turned to the "OFF" posi-
tion then to the "ON" position again.
.
CIRCUIT OPERATION
ABS/TCL-ECU terminal 21 is grounded every time
the TCL switch is pressed. ABS/TCL-ECU monitors
this operation state and turns the TCL ON or OFF.
.
COMMENT
The cause is probably an open-circuit in the TCL
switch circuit.
.
TROUBLESHOOTING HINTS
Malfunction of the TCL switch.
Damaged harness or connector.
Malfunction of the ABS/TCL-ECU.
DIAGNOSIS
Required Special Tools:
MB991223: Harness Set
MB991219: Inspection Test Harness
Page 1313 of 1500

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-34
INSPECTION PROCEDURE 6: TCL does not Operate.
NOTE: If the ABS-8 ECU or the active wheel
speed sensor are disconnected, or if the wiring is
an open/ short circuit, the ABS 8 ECU will shut
off power supply to the respective wheel speed
sensor. All other wheel speed sensors will oper-
ate normally. To restore the power supply, the
ignition switch must be turned to the "OFF" posi-
tion then to the "ON" position again.
.
COMMENT
The fail-safe function is probably cancelling TCL. In
this case, diagnostic tool MB991958 can be used to
retest each system by checking the diagnostic trou-
ble codes.
.
TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CASE:)
Malfunction of the CAN bus line.
Malfunction of the MPI system.
Malfunction of the A/T system.
Malfunction of the ABS/TCL-ECU.
DIAGNOSIS
Required Special Tools:
MB991958: Diagnostic Tool (MUT-III Sub Assembly)
MB991824: V.C.I.
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A
STEP 1. Using diagnostic tool MB991958, read the
diagnostic trouble code.
To prevent damage to diagnostic tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting diagnostic tool
MB991958.
(1) Connect diagnostic tool MB991958 to the data link
connector. (Refer to P.13C-3).
(2) Turn the ignition switch to the "ON" position.
(3) Use diagnostic tool MB991958 to read the TCL diagnostic
trouble codes. (Refer to P.13C-3).
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect diagnostic tool MB991958.
Q: Is any DTC set?
YES : Repair the TCL. (Refer to P.13C-8, Diagnostic
Trouble Code Chart). Then go to Step 4.
NO : Go to Step 2.
Page 1315 of 1500

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-36
DATA LIST REFERENCE TABLEM1136003500071
NOTE: If the ABS-8 ECU or the active wheel
speed sensor are disconnected, or if the wiring is
an open/ short circuit, the ABS 8 ECU will shut
off power supply to the respective wheel speed
sensor. All other wheel speed sensors will oper-
ate normally. To restore the power supply, the
ignition switch must be turned to the "OFF" posi-
tion then to the "ON" position again.The following items can be read by the diagnostic
tool from the ABS/TCL-ECU input data. (Refer to
P.13C-3).
NOTE: Since the TCL is controlled with the same ABS/TCL-ECU used to control the ABS, the stoplight switch
check item (No.6) used only for the ABS also appear.MUT-III
DIAGNOSTI
C TOOL
DISPLAYITEM
NO.CHECK ITEM CHECKING REQUIREMENTS NORMAL
VA L U E
FL wheel
speed sensor01 Front left wheel speed sensor Drive the vehicle Vehicle speeds
displayed on the
speedometer
and diagnostic
tool are identical. FR wheel
speed sensor02 Front right wheel speed sensor
RL wheel
speed sensor03 Rear left wheel speed sensor
RR wheel
speed sensor04 Rear right left wheel speed
sensor
Power supply
voltage05 ABS/TCL-ECU power supply
voltageIgnition switch power supply
voltageBattery positive
voltage
Stoplamp
switch
(input)*06 Stoplamp switch Depress the brake pedal. ON
Release the brake pedal. OFF
Stoplamp
switch*13 Stoplamp switch Depress the brake pedal. ON
Release the brake pedal. OFF
Pump motor 21 Pump motor When the ABS outputs the
operation permission signal
during drivingON
When the ABS outputs the
operation permission signal
during drivingOFF
Valve relay 30 Valve relayWhen the ABS outputs the
operation permission signal
during drivingON
When the ABS outputs the
operation permission signal
during drivingOFF
TCL mode 35 TCL operation When the TCL outputs the
operation permission signal
during drivingON
When the TCL outputs the
operation inhibition signal
during drivingOFF
Page 1316 of 1500

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-37
ACTUATOR TEST REFERENCE TABLEM1136003600067
NOTE: If the ABS-8 ECU or the active wheel
speed sensor are disconnected, or if the wiring is
an open/ short circuit, the ABS 8 ECU will shut
off power supply to the respective wheel speed
sensor. All other wheel speed sensors will oper-
ate normally. To restore the power supply, the
ignition switch must be turned to the "OFF" posi-
tion then to the "ON" position again.The diagnostic tool activates the following actuators
for testing. (Refer to P.13C-3).
NOTE: Since the TCL is controlled with the same ABS/TCL-ECU used to control the ABS, the FL, FR, RL or
RR Wheel ABS Drive testing items (No.01 to 04) used only for the ABS also appear. MUT-III
DIAGNOSTIC TOOL
DISPLAYITEM NO. CHECK ITEM PARTS TO BE ACTIVATED
FL wheel ABS Drive* 01 Solenoid valve for front left wheel Solenoid valves and pump
motors in the hydraulic unit
(simple inspection mode) FR wheel ABS Drive* 02 Solenoid valve for front right wheel
RL wheel ABS Drive* 03 Solenoid valve for rear left wheel
RR wheel ABS
Drive*04 Solenoid valve for rear right wheel
Engine TCL Drive 09 TCL operation check Outputs the engine torque
control signal (engine torque =
0) to PCM for three seconds.
Page 1318 of 1500
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-39
RESISTANCE AND CONTINUITY BETWEEN
ABS-ECU AND WHEEL SPEED SENSOR
HARNESS-SIDE CONNECTOR TERMINALS
.
Required Special Tools:
MB991219: Inspection Test Harness
MB991223: Harness Set
1. Disconnect the ABS/TCL-ECU connector A-02 and the
related wheel speed sensor connector, then turn the ignition
switch to the "LOCK" (OFF) position.
2. Measure the resistance and continuity between the
ABS/TCL-ECU wiring harness-side connector A-02 and the
Wheel Speed Sensor connectors using the Inspection test
harness MB991219 (by inserting probe) and an ohmmeter
between terminals shown in the table below.
NOTE: The special tool (Inspection test harness) MB991219
for connector pin contact pressure should be used. The test
probe should never be forcibly inserted, as it may cause a
defective contact.
3. The terminal layout is shown in the table below.
Page 1319 of 1500
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-40
SIGNAL TERMINAL NO. NORMAL CONDITION
ABS (A-02) SENSOR
FR wheel speed sensor
(A-01)9 2 Less than 2 ohms
10 1 Less than 2 ohms
RR wheel speed sensor
(D-30)8 1 Less than 2 ohms
19 2 Less than 2 ohms
FL wheel speed sensor
(A-04)16 2 Less than 2 ohms
5 1 Less than 2 ohms
RL wheel speed sensor
(D-31)6 1 Less than 2 ohms
17 2 Less than 2 ohms
Page 1320 of 1500

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-41
VOLTAGE AND SIGNAL CHECK AT ABS-ECU
(A-02) USING OSCILLOSCOPE
NOTE: If the ABS-8 ECU or the active wheel speed
sensor are disconnected, or if the wiring is an open/
short circuit, the ABS 8 ECU will shut off power sup-
ply to the respective wheel speed sensor. All other
wheel speed sensors will operate normally. To
restore the power supply, the ignition switch must be
turned to the "OFF" position then to the "ON" position
again..
WHEEL SPEED SENSOR AIR GAP:
Sensor air gap: (0.2mm - 0.85mm).
.
Measure supply voltage for wheel speed sensor using an
oscilloscope.
(1) ABS-ECU must remain connected.
(2) Wheel speed sensors must emain connected
(3) Remove ABS connector protection cap to access terminal
location from the rear of connector for back-probing.
(4) Using probe (MB991222) , backprobe the wheel speed
sensor voltage supply circuit terminals (16, 9, 6 and 8) at
the ABS-ECU connector (A-02) individually.
(5) Connect oscilloscope (as per figure 1) shows, to the
appropriate terminal positions and check supply voltage
individually with scope.
Page 1321 of 1500
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-42
Connect oscilloscope to FL sensor signal terminal (16)
at ABS-ECU (A-02)
Connect oscilloscope to FR sensor signal terminal (9) at
ABS-ECU (A-02)
Connect oscilloscope to RL sensor signal terminal (6) at
ABS-ECU (A-02)
Connect oscilloscope to RR sensor signal terminal (8) at
ABS-ECU (A-02)
(6) Turn the ignition switch to the "ON" position.