Page 1389 of 1500

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-58
STEP 3. Using Diagnostic ToolDiagnostic Tool MB991958,
check data list item 74: Stoplamp Switch and data list item
89: Brake switch.
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) Set Diagnostic Tool MB991958 to data reading mode for
auto-cruise control system. (Refer to P.17-11).
Item 74, Stoplamp Switch.
When brake pedal is depressed, the display on
Diagnostic Tool MB991958 should be "ON".
When brake pedal is released, the display on
Diagnostic Tool MB991958 should be "OFF".
Item 89, Brake Switch.
When brake pedal is depressed, the display on
Diagnostic Tool MB991958 should be "ON".
When brake pedal is released, the display on
Diagnostic Tool MB991958 should be "OFF".
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect Diagnostic Tool MB991958.
Q: Is the switch operating properly?
YES : Go to Step 4.
NO : Refer to P.17-54, Symptom Procedures
Inspection
Procedure 1. Then go to Step 6.
Page 1390 of 1500

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-59
STEP 4. Using Diagnostic Tool MB991958, check A/T data
list item 34: Transmission Inhibitor Switch.
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) Set Diagnostic Tool MB991958 to data reading mode for
Auto Transmission system. (Refer to P.17-11).
Item 34, Transmission Inhibitor Switch.
When selector lever is at the "P" or "N" position, the
display on Diagnostic Tool MB991958 should be
"ON".
When selector lever is at the "R" or "D" position, the
display on Diagnostic Tool MB991958 should be
"OFF".
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect Diagnostic Tool MB991958.
Q: Is the switch operating properly?
YES : Go to Step 5.
NO : Refer to P.17-54, Symptom Procedures
Inspection
Procedure 2. Then go to Step 6.
STEP 5. Check the symptoms.
Q: Can auto-cruise control be set?
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 Engine ECU.[Refer to GROUP 13A,
Engine ECU 13A-675] . Then go to Step 6.
STEP 6. Check the symptoms.
Q: Can auto-cruise control be set?
YES : The procedure is complete.
NO : Return to Step 1.
Page 1391 of 1500

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-60
INSPECTION PROCEDURE 6: Hunting (Repeated Acceleration and Deceleration) Occurs at the Set
Vehicle Speed.
.
COMMENT
The output shaft speed sensor signal or the throttle
body is suspected.
.
TROUBLESHOOTING HINTS (THE MOST
LIKELY CAUSES FOR THIS CASE:)
Malfunction of the output shaft speed sensor.
Malfunction of the throttle body.
Malfunction of the Engine ECU.
Malfunction of the A/T ECU.
Circuit drawings
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
Refer to component locations GROUP-70
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.17-11).
(2) Turn the ignition switch to the "ON" position.
(3) Check for A/T system diagnostic trouble code. (Refer to
GROUP 23A, A/T Diagnosis
Diagnostic Function How
to Read and Erase Diagnostic Trouble Code P.23A-13).
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect Diagnostic Tool MB991958.
Q: Is any DTC set?
YES : Diagnose the A/T system. (Refer to GROUP 23A, A/T
Diagnosis
Diagnostic Trouble Code Chart
P.23A-34). Then go to Step 4.
NO : Go to Step 2.
Page 1392 of 1500

AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-61
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.17-11).
(2) Turn the ignition switch to the "ON" position.
(3) Check for MPI system diagnostic trouble code(Refer to
GROUP 13A, MPI Diagnosis
Diagnostic Function How
to Read and Erase Diagnostic Trouble Code 13A-6).
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect Diagnostic Tool MB991958.
Q: Is any DTC set?
YES : Diagnose the MPI system. (Refer to GROUP 13A,
MPI Diagnosis
Diagnostic Trouble Code Chart
13A-17). Then go to Step 4.
NO : Go to Step 3.
STEP 3. Retest the system
Q: Does hunting occur?
YES : Replace the Engine ECU[Refer to GROUP 13A,
Engine ECU 13A-675]. Then go to Step 4.
NO : 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).
STEP 4. Retest the system
Q: Does hunting occur?
YES : Return to Step 1.
NO : The procedure is complete.
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AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-63
CIRCUIT OPERATION
The Engine ECU detects "CRUISE" (MAIN) switch
"ON" signal to illuminate the "CRUISE" indicator
lamp on the combination meter.
.
COMMENT
Connector(s), wiring harness in the CAN bus line
between the Engine ECU and the combination
meter, power supply to the Engine ECU, the combi-
nation meter, the Engine ECU may be defective.
.
TROUBLESHOOTING HINTS
Malfunction of the combination meter.
Damaged harness or connector.
Malfunction of the Engine ECU.
Circuit drawings
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
Refer to component locations GROUP-70
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.17-11).
(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line. (Refer to P.17-11).
(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.
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AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-64
STEP 2. Using Diagnostic Tool MB991958, read the MPI
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 MPI system diagnostic trouble code(Refer to
GROUP 13A, MPI Diagnosis
Diagnostic Function How
to Read and Erase Diagnostic Trouble Code 13A-6).
(4) Turn the ignition switch to the "LOCK" (OFF) position.
(5) Disconnect Diagnostic Tool MB991958.
Q: Is DTC U1108 set?
YES : . Then go to Step 4.
NO : Go to Step 3.
STEP 3. Retest the system.
Q: Does the "CRUISE" indicator lamp illuminate when the
"CRUISE" (MAIN) switch is turned "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 Engine ECU. [Refer to GROUP 13A,
Engine ECU 13A-675]. Then go to Step 4.
STEP 4. Retest the system.
Q: Does the "CRUISE" indicator lamp illuminate when the
"CRUISE" (MAIN) switch is turned "ON"?
YES : The procedure is complete.
NO : Return to Step 1.
Page 1406 of 1500
AUTO-CRUISE CONTROL
ENGINE AND EMISSION CONTROL17-75
AUTO-CRUISE CONTROL
REMOVAL AND INSTALLATIONM1172001400467
Before removal of the air bag module, refer to GROUP 52B, SRS Service Precautions
P.52B-16 and GROUP 52B, Air Bag Module and Clock Spring P.52B-237.
CONTROL SWITCH REMOVAL
STEPS
1. AIR BAG MODULE
SIDE> (REFER TO GROUP 52B, AIR
BAG MODULES AND CLOCK
SPRING P.52B-237)
2. STEERING WHEEL ASSEMBLY
(REFER TO GROUP 37, STEERING
WHEEL P.37-23)
3. LOWER COVER CAP
4. AUTO-CRUISE CONTROL SWITCH
CONTROL UNIT REMOVAL
5. Engine ECU [REFER TO GROUP
13A, Engine ECU 13A-675] SENSOR REMOVAL STEPS
6. TRANSMISSION INHIBITOR
SWITCH (REFER TO GROUP 23B,
AUTOMATIC TRANSMISSION)
7. THROTTLE BODY (BUILT-IN
THROTTLE POSITION SENSOR
AND THROTTLE ACTUATOR
CONTROL MOTOR) (REFER TO
GROUP 13A, THROTTLE BODY
13A-660)
8. ACCELERATOR PEDAL (BUILT-IN
ACCELERATOR PEDAL POSITION
SENSOR) (REFER TO GROUP 17,
ACCELERATOR PEDAL P.17-9)
9. STOPLIGHT SWITCH (REFER TO
GROUP 35A, BRAKE PEDAL
P.35A-24)
Page 1426 of 1500