Section 142 (Dynamic Laser Cruise Control System - Diagnosis): Pre-Check

WARNING: This page is about a different car, the 2004 Toyota Sienna. However, it is still accessible from the selected car via links, so may be relevant.

DYNAMIC LASER CRUISE CONTROL SYSTEM DESCRIPTION
1. This system maintains the vehicle running at the fixed speed that the driver has set, as long as there are no vehicles ahead in the same lane. Then, the system maintains the vehicle distance that has been set by the driver.
  If the system detects a front vehicle moving slower speed than one's own vehicle while the driver is driving at a fixed speed, it closes the throttle valve to decelerate. If additional deceleration is necessary, it shifts the gears down to decelerate. If further deceleration is required, the system controls the brake actuator in order to apply the brakes. Thereafter, if there are no front vehicles within the set vehicle-to-vehicle distance because either the vehicle in front or the driver has changed lanes, the system accelerates slowly to reach the set vehicle speed and resumes driving at the fixed speed.
2. (fixed speed) cruise control mode that effects control only to maintain a fixed cruising speed. The vehicle-to-vehicle distance control mode that effects cruising at a fixed speed function, deceleration cruising function, follow-up cruising function, and acceleration cruising function. These two modes can be switched by operating the cruise control main switch.
3. A steering pad switch (Distance control switch) for setting the distance to the front vehicle is provided on the steering wheel pad.
  With this switch, the vehicle distance can be set in the following three stages: LONG, MIDDLE, and SHORT.
LASER BEAM AXIS ADJUSTMENT
Use the hand-held tester to adjust to the optical axis, see dynamic laser cruise control system for the optical axis adjusting operation.

HINT:

While adjusting the optical axis of the laser radar sensor, the CRUISE main indicator light illuminates and FC is displayed on the multi-information display.
DIAGNOSIS FUNCTION
1. The diagnosis function makes the master warning light and the multi-information display to comes on, and CRUISE main indicator light blinks as shown in the illustration, when a malfunction occurs in the dynamic laser cruise control system, and store the diagnosed result in the ECM.
Fig 1: Identifying Cruise Main Indicator Light
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NOTE:
- The master warning light goes off if the system returns to normal condition.
- Since the stored data in the ECM is erased by disconnecting the EFI fuse and the battery terminal, do not disconnect them until finishing the inspection.
Fig 2: Identifying Cruise Main Indicator Light Blinking Pattern
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DIAGNOSING SYSTEM

Description
The ECM controls the function of cruise control and dynamic laser cruise control on a vehicle. Data on the cruise control system, dynamic laser cruise control system and the DTCs can be read from DLC3 on the vehicle. If the CRUISE main indicator does not come on after the DTC check, there is a malfunction on the cruise control and dynamic laser cruise control system.

Use the hand-held tester or SST check wire to check and solve the problem.

SST 09843-18040

Check the DLC3.

The vehicle's ECM uses ISO 9141-2 for communication. The terminal arrangement of DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.

Fig 3: Identifying DLC3 Connector Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

SPECIFIED CONDITION

Terminal No.	Connection/Specified Condition	Condition
4	Chassis Ground <--> Body Ground/1 Ω or less	Always
7	Bus <--> Line/Pulse Generation	During Communication
16	Battery Positive <--> Body Ground/9 to 14 V	Always

HINT:

If the display shows "UNABLE TO CONNECT TO VEHICLE" when the hand-held tester is connected to the DLC3 and the ignition switch is ON, there is a problem on either the vehicle or the tool.

If communication is normal when the tool is connected to another vehicle, check DLC3 on the original vehicle.
If communication is still not possible when the tool is connected to another vehicle, the problem is probably in the tool itself. Consult with the Service Department listed in the tool's instruction manual.

Check the indicator.
1. Turn the ignition switch ON.
2. Check that the CRUISE main indicator light and READY indicator light comes on when the cruise control main switch is turned on. Then, the indicator light goes off when the main switch is turned off.
HINT:

If the indicator check result shows problem, proceed to troubleshooting, see HOW TO PROCEED WITH TROUBLESHOOTING , for the combination meter section.

Fig 4: Identifying Cruise Main Indicator Light
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Check the DTCs.
HINT:

If a malfunction occurs in the vehicle speed sensors or the stop lamp switch, etc. during cruise control driving, the ECU actuates AUTO CANCEL of the cruise control and blinks CRUISE main indicator light. This indicator light inform malfunction to the driver. At the same time, the malfunction date is stored as a diagnostic trouble code.

Fig 5: Cruise Main Indicator Light Blinking Pattern
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Check the output of the DTCs using diagnosis check wire.
1. Turn the ignition switch ON.
2. Using SST check wire, connect terminals TC and CG of DLC3.
  SST 09843-18040
3. Read the DTC on the CRUISE main indicator light.
Fig 6: Identifying DLC3 Connector Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

If the DTCs are not indicated, inspect the CRUISE MAIN INDICATOR LIGHT CIRCUIT and the DIAGNOSIS CIRCUIT .

For example, the blinking patterns of normal code and code 52 are shown in the illustration.

Fig 7: Identifying Normal Blinking Pattern And Blinking Pattern For Code 52

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

AUTO CANCEL FUNCTION (FAIL-SAFE FUNCTION)
HINT:

If a system malfunction occurs, the applicable DTCs (Diagnostic Trouble Codes) will appear on the multi-information display.
1. The cruise main indicator keeps blinking until turning the main switch off, the master warning light comes on with the warning sound "Pop", and the display shows "E3". The cruise control operation is suspended until turning the main switch to ON again. The auto cancel function deletes the stored vehicle speed and cancels the cruise control operation in the following conditions.
  
  Fig 8: Identifying "E3" Screen Display In Multi-Information Display
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. When the vehicle speed signal malfunctions.
  2. When the electronic throttle parts malfunction.
  3. When the stop lamp switch is open or short circuit.
  4. When the laser radar sensor malfunctions. (*1)
  5. When the light axis of the laser radar sensor is off the position. (*1)
  *1: Only in the Vehicle-to-vehicle Distance Control Mode.
2. The cruise main indicator blinks, the master warning light comes on with the warning sound "Pop", and the display shows "E2". The cruise control operation is suspended until the canceling condition is resolved (in the Vehicle-to vehicle Distance Control Mode only). The auto cancel function cancels the cruise control operation in the following conditions.
  1. When the wipers (Hi, Lo) operate (including the auto wiper).
  2. When the pattern select switch is in the "SNOW" mode.
  3. When the laser radar sensor receives strong light, such as sunlight, from the front side.
  4. When the Vehicle-to-vehicle distance measurement is extremely unstable because of a bad weather.
  Fig 9: Identifying "E2" Screen Display In Multi-Information Display
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. The auto cancel function cancels the cruise control operation in the following conditions. At this time, the cruise main indicator blinks, the master warning light comes on with the warning sound "Pop" and the display shows "E1". The cruise control operation is suspended until the canceling condition is resolved (in the Vehicle-to vehicle Distance Control Mode only).
  1. When the laser radar sensor has dirt on it.
  HINT:
  
  While the dynamic laser cruise control is operated, the ECM outputs a malfunction code when it detects dirt for 0.15 sec. or more.
Fig 10: Identifying "E1" Screen Display In Multi-Information Display
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
USING HAND-HELD TESTER
1. Hook up the hand-held tester to the DLC3.
2. Monitor the ECU data by following the prompts on the tester screen.
HINT:

The hand-held tester has the "Snapshot" function which records the monitored data.

Refer to the hand-held tester operator's manual for further details.

Fig 11: Connecting Hand-Held Tester To DLC3
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
DATA LIST
HINT:

From the DATA LIST displayed by the hand-held tester, you can read the value of the switch, sensor, actuator and so on without parts removal. Reading the DATA LIST as the first step of troubleshooting is one of the way to shorten labor time.
1. Connect the Hand-held tester to the DLC3.
2. Turn the ignition switch ON.
3. According to the display on the tester, read the "DATA LIST".
ECM:

Fig 12: Data List - ECM (1 Of 2)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 13: Data List - ECM (2 Of 2)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

ACTIVE TEST

HINT:

Performing the ACTIVE TEST using the hand-held tester allows the relay, VSV, actuator and so on to operate without parts removal. Performing the ACTIVE TEST as a first step of troubleshooting is one of the method to shorten the labor time.

It is possible to display the DATA LIST during the ACTIVE TEST.

Connect the hand-held tester to the DLC3.
Turn the ignition switch ON.
According to the display on tester, perform the "ACTIVE TEST".

HINT:

IG must be turned ON to proceed Active Test using a hand-held tester.

SKID CONTROL ECU:

SKID CONTROL ECU DIAGNOSTIC CHART

Item	Vehicle Condition/Test Details	Diagnostic Note
VSC / BR WARN BUZ	Turns VSC / BRAKE warning buzzer ON / OFF	Buzzer can be heard
STP LIGHT RELAY	Turns BRK relay ON / OFF	-

DTC CLEAR
1. Following actions will erase the DTCs and the freeze frame data.
  1. Hand-held Tester:
    Operating the hand-held tester to erase the codes.
  2. Except hand-held Tester:
    Disconnecting the battery terminals or EFI fuse.
2. After completing repairs, stored DTCs in the memory can be cleared by removing the EFI fuse for 1 minutes or more with the ignition switch off.
3. Check that the normal code is displayed after connecting the fuse.
PROBLEM SYMPTOM CONFIRMATION (ROAD TEST)
1. Inspect the SET switch.
  1. Push the main switch to ON.
  2. Drive at a desired speed (40 km/h (25 mph) or higher).
  3. Press the control switch towards the - SET.
  4. After releasing the switch, check that the vehicle cruises at the desired speed.
  Fig 14: Inspecting SET Switch
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Inspect the + (ACCEL) switch.
  1. Push the main switch to ON.
  2. Drive at a desired speed (40 km/h (25 mph) or higher).
  3. Check that the vehicle speed increase while the control switch is pressed towards + RES, and that the vehicle cruises at the set speed when the switch is released.
  4. Momentarily press the control switch towards the + RES and then immediately release it. Check that the vehicle speed increases by about 1.6 km/h (1.0 mph) (Tap-up function).
  Fig 15: Inspecting + (ACCEL) Switch
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  HINT:
  
  Tap-up/Tap-down function can be used only in the fixed-speed Control Mode.
3. Inspect the - (COAST) switch.
  1. Push the main switch to ON.
  2. Drive at a desired speed (40 km/h (25 mph) or higher).
  3. Check that the vehicle speed decrease while the control switch is pressed towards to - SET, and the vehicle cruises at the set speed when the switch is released.
  4. Momentarily press the control switch towards to - SET, and then immediately release it. Check that the vehicle speed decrease by about 1.6 km/h (1.0 mph) (Tap-down function).
  Fig 16: Inspecting - (COAST) Switch
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  HINT:
  
  Tap-up/Tap-down function can be used only in the fixed-speed Control Mode.
4. Inspect the CANCEL switch.
  1. Push the main switch to ON.
  2. Drive at a desired speed (40 km/h (25 mph) or higher).
  3. When operating one of the followings, check that the cruise control system is cancelled and that the normal driving mode is reset.
    - Depress the brake pedal
    - Shift to except D position
    - Push the main switch button to OFF
    - Pull the cruise control switch to CANCEL
  Fig 17: Inspecting CANCEL Switch
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Inspect the + (RESUME) switch.
  1. Push the main switch button to ON.
  2. Drive at desired speed (40 km/h (25 mph) or higher).
  3. When operating one of the followings, check that the cruise control system is cancelled and that the normal driving mode is reset.
    - Depress the brake pedal
    - Shift to except D position
    - Pull the cruise control switch to CANCEL
    Fig 18: Inspecting + (RESUME) Switch
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. After pressing up the control switch towards + RES at the driving speed of more than 40 km/h (25 mph), check that the vehicle restores the speed prior to the cancellation.
  5. RESUME (in the Vehicle-to-vehicle Distance Control Mode only.)
  HINT:
  
  The stored vehicle speed is retained even if the vehicle speed becomes less than 40 km/h (25 mph) once. The previously stored vehicle speed can be resumed by pressing the cruise control main switch assembly towards the "+ RES" when vehicle speed returned to approx. 40 km/h (25 mph) or more.
INPUT SIGNAL CHECK (Using hand-held tester)
1. Connect the hand-held tester to DLC3
2. Check the cruise control main switch using the DATA LIST function in hand-held tester (MAIN, CANCEL, -SET, +RES, MODE).
Fig 19: Checking Cruise Control Main Switch
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 20: Checking Input Signal Using Hand-Held Tester
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT MODE SWITCH
1. Turn the ignition switch ON.
2. After pressing on the main switch of the cruise control main switch, press the cruise control main switch towards the MODE position for at least 1 second without any other control. After no indication is shown in the display, make sure that "NORM. (set vehicle speed)" is indicated.
NOTE: When performing other operations (setting) after turning the main switch on, the system cancels the constant speed control mode and cannot return to the mode again.

Fig 21: Inspecting Mode Switch (1 Of 2)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

If the system cannot switch to the constant speed control mode, turn the main switch off once, and perform the same procedures as shown above. If a malfunction is still detected in the system, and then start the engine again and perform the above procedure.

Fig 22: Inspecting Mode Switch (2 Of 2)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT STEERING PAD SWITCH assembly
1. Turn the ignition switch ON.
2. Press the main switch of the cruise control main switch.
3. Press the distance control switch of the steering pad switch.
4. Check that the indication of distance between vehicles, which are shown on the multi-information display of the combination meter, changes from "LONG", "MEDDLE" to "SHORT" in order.
HINT:

The indication is immediately set to (LONG) after starting the engine.

Fig 23: Inspecting Steering Pad Switch Assembly
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002