TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-22
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 U1120 set?
YES : Return to Step 1.
NO : The procedure is complete.
U1400 Dynamic range error APS1
.
DTC SET CONDITION
This code is set when the MPI system sets either of
DTCs P2138, P2122 or P2123.
.
TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THESE DTCS ARE
TO SET ARE:)
Malfunction of the MPI system
DIAGNOSIS
Check whether the MPI system sets either of diagnostic trouble
codes P2138, P2122 or P2123, and repair if necessary. (Refer
to GROUP 13A, MPI Diagnosis
Diagnostic Function How to
Read and Erase Diagnostic Trouble Code P.13A-6).
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-26
COMMENT
This may be caused by faults in the CAN bus line,
the combination meter or the ABS/TCL-ECU.
.
TROUBLESHOOTING HINTS
Malfunction of the combination meter.
Damaged harness or connector.
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, diagnose the
CAN bus line.
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) Diagnose the CAN bus line. (Refer to P.13C-3).
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect diagnostic tool MB991958.
Q: Is the check result satisfactory?
YES : Go to Step 2
NO : Repair the CAN bus lines. (Refer to GROUP 54C,
Diagnosis
Can Bus Diagnostic Chart P.54C-15).
Then go to Step 4.
TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS
TRACTION CONTROL SYSTEM (TCL)13C-27
STEP 2. 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 : Refer to P.13C-8, Diagnostic Trouble Code Chart.
Then go to Step 4.
NO : Go to Step 3.
STEP 3. 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.17-11).
(2) Turn the ignition switch to the "ON" position.
(3) Check for Combination meter system diagnostic trouble
code. (Refer to GROUP 54A, Combination Meter Assembly
Diagnosis
Diagnosis Function How to Read and Erase
Diagnostic Trouble Code P.54A-46).
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect diagnostic tool MB991958.
Q: Is DTC U1102 set?
YES : Replace the hydraulic unit (integrated with
ABS/TCL-ECU). (Refer to GROUP 35B
Hydraulic
Unit P.35B-93). Then go to Step 4.
NO : Replace the combination meter assembly. (Refer to
GROUP 54A
Combination Meter Assembly
P.54A-142). Then go to Step 4.
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-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.
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.
ON-VEHICLE SERVICE
TRACTION CONTROL SYSTEM (TCL)13C-48
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 sec-
onds.
4. Turn the ignition switch to the "LOCK" (OFF) position.
5. Disconnect diagnostic tool MB991958.
6. If defective, repair it. (Refer to P.13C-34, TCL diagnosis
Symptom Procedures
Inspection Procedure 6).
TCL SWITCH CHECKM1136001700024
1. Remove the TCL switch. (Refer to P.13C-49).
2. Measure the resistance between terminal 1 and terminal 2
when the TCL switch is pressed or released. If the values
measured at the time correspond to those in the table below,
the resistance values are correct.
WHEEL SPEED SENSOR CHECKM1136001300026
Refer to GROUP 35B, On-vehicle Service P.35B-88.
SWITCH
POSITIONTESTER
CONNECTIONSPECIFIED
CONDITION
Pressed 1-2 Less than 2
ohms
Released 1-2 Open circuit