Page 1308 of 1500

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.
Page 1310 of 1500
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-31
STEP 3. Check ABS/TCL-ECU connector A-02,
intermediate connector C-29 and TCL switch connectors
C-131 for loose, corroded or damaged terminals, or
terminals pushed back in the connector.
Q: Are there connectors and terminals in good condition?
YES : Go to Step 4.
NO : Repair or replace the faulty connector. (Refer to
GROUP 00E, Harness Connector Inspection
P.00E-2). Then go to Step 7.
Page 1311 of 1500
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-32
STEP 4. Check the harness wire between ABS/TCL-ECU
connector A-02 terminal 21 and TCL switch connector
C-131 terminal 1 for damage.
Q: Are there harness wires in good condition?
YES : Go to Step 5.
NO : Repair the damaged harness wire. Then go to Step 7.
Page 1312 of 1500
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-33
STEP 5. Check the harness wire between TCL switch
connector C-131 terminal 2 and ground for damage.
Q: Is the harness wire in good condition?
YES : Go to Step 6.
NO : Repair the damaged harness wire. Then go to Step 7.
STEP 6. Retest the system
Q: Does TCL system cancel, when the TCL switch is
pushed on?
YES : It can be assumed that this malfunction is intermittent.
(Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points
How to
Cope with Intermittent Malfunction P.00-14).
NO : Replace the hydraulic unit (integrated with
ABS/TCL-ECU). (Refer to GROUP 35B
Hydraulic
Unit P.35B-93). Then go to Step 7.
STEP 7. Retest the system
Q: Does TCL system cancel, when the TCL switch is
pushed on?
YES : The procedure is complete.
NO : Return to Step 1.
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 1314 of 1500

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-35
STEP 2. Using diagnostic tool MB991958, check TCL
actuator test item09: Engine TCL Drive.
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.
The engine speed increases after the actuator test
because the actuator test continues for only three sec-
onds. Therefore, release the accelerator pedal immedi-
ately.
(3) Use diagnostic tool MB991958 to check the actuator test.
(Refer to P.13C-3).
Item 09: Engine TCL Drive.
When the accelerator pedal is depressed at the
same time that the button for actuator test item 09
displayed on diagnostic tool MB991958 is pressed,
the system prevents the engine speed from rising for
three seconds.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect diagnostic tool MB991958.
Q: Are the check results for actuator test item 09
satisfactory?
YES : Go to Step 3.
NO : Replace the hydraulic unit (integrated with
ABS/TCL-ECU). (Refer to GROUP 35B
Hydraulic
Unit P.35B-93). Then go to Step 4.
STEP 3. Retest the system
Q: Does the TCL work normally?
YES : It can be assumed that this malfunction is intermittent.
(Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points
How to
Cope with Intermittent Malfunction P.00-14).
NO : Replace the hydraulic unit (integrated with
ABS/TCL-ECU). (Refer to GROUP 35B
Hydraulic
Unit P.35B-93). Then go to Step 4.
STEP 4. Retest the system
Q: Does the TCL work normally?
YES : The procedure is complete.
NO : Return to Step 1.
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.