TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-14
STEP 6. 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 DTC U1100 set?
YES : Return to Step 1.
NO : The procedure is complete.
U1101 CAN Communications System Time Out Error A/T Related Data
If DTC U1101 is set in the ABS/TCL-ECU,
always diagnose the CAN main bus line. If
there is any fault in the CAN bus lines, an
incorrect DTC may be set.
Whenever the ABS/TCL-ECU is replaced,
ensure that the communication circuit is nor-
mal.
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.
.
DTC SET CONDITION
The ABS/TCL-ECU receives A/T system-related sig-
nals from the A/T-ECU via CAN bus lines.
.
TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THESE DTCS ARE
TO SET ARE:)
Damaged harness or connector.
Malfunction of the A/T-ECU.
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
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-18
STEP 6. 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 DTC U1101 set?
YES : Return to Step 1.
NO : The procedure is complete.
U1120 CAN Communications System TCL Uncontrollable by Engine Malfunction
If DTC U1120 is set in the ABS/TCL-ECU,
always diagnose the CAN main bus line. If
there is any fault in the CAN bus lines, an
incorrect DTC may be set.
Whenever the ABS/TCL-ECU is replaced,
ensure that the communication circuit is nor-
mal.
The engine control system-related DTC may
be set when DTC U1120 is set. (For details
refer to GROUP 00, Intersystem Affiliated DTC
Reference Table P.00-17). Diagnose the
engine control system first when the engine
control system-related DTC is set.
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.
.
DTC SET CONDITION
The ABS/TCL-ECU receives engine system-related
signals from the Engine-ECU via CAN bus lines. If a
fail-safe related data is contained in the signal from
the Engine-ECU, DTC U1120 will be stored.
.
TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THESE DTCS ARE
TO SET ARE:)
Damaged harness or connector.
Malfunction of the Engine-ECU.
Malfunction of the ABS/TCL-ECU.
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-24
.
CIRCUIT OPERATION
The TCL automatically goes to ON, when the
ignition is turned to the "ON" position. To deacti-
vate the TCL, press the TCL switch. To reactivate
the TCL , press the TCL switch again.
ABS/TCL-ECU send the illumination signal of
"TCL OFF" indicator light and TCL work indicator
light to the combination meter via the CAN com-
munication.
ABS/TCL-ECU operates the "TCL OFF" indicator
light and the TCL work indicator light for three
seconds after the ignition switch is turned "ON"
position for bulb check.
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-25
NOTE: If you press the TCL switch to deactivate the
TCL and then keep the TCL switch pressed for about
10 seconds, an error prevention function will auto-
matically reactivate the TCL. If you then still wish to
deactivate the TCL, press the TCL switch again to
deactivate it.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.
.
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
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-29
STEP 1. Measure the resistance at ABS/TCL-ECU
connector A-02.
(1) Disconnect the ABS/TCL-ECU connector A-02.
(2) Measure the resistance at the ABS/TCL-ECU wiring
harness-side connector A-02 using the Inspection test
harness MB991219 (by inserting probe) and body ground.
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) Turn the ignition switch to the "OFF" position.
(4) Measure the resistance by probing ABS/TCL-ECU
connector A-02 terminal 21 (using inspection test harness
MB991219) and ground.
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.
When the TCL switch is not pressed, the resistance
should indicate an open circuit (more than 2 ohms).
When the TCL switch is pressed, the resistance should
measure 2 ohms or less.
(5) Turn the ignition switch to the "LOCK" (OFF) position.
(6) Disconnect inspection test harness MB991219.
(7) Connect the ABS/TCL-ECU connector A-02.
Q: Is the resistance value more than 2 ohms when the TCL
switch is not pressed, and is the resistance value less
than 2 ohms when the TCL switch is pressed?
YES : Go to Step 6.
NO : Go to Step 2.
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.
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