Section 481 (Cruise Control System): Pre-Check

1. Check the indicator.
   1. Turn the ignition switch to ON.
   2. Check that the CRUISE MAIN indicator light comes on when the cruise control main switch is turned ON, and that the indicator light goes off when the main switch is turned OFF.

      HINT:

      If the indicator check result is not normal, proceed to troubleshooting (See TROUBLE SHOOTING ) for the combination meter section.

      Fig 1: Identifying Cruise Main Indicator Light

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the DLC3.

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

   Fig 2: Identifying Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   Fig 3: Connection Specified Condition Table

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   HINT:

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

   • If communication is normal when connecting the LEXUS hand-held tester to another vehicle, inspect the DLC3 on the original vehicle.
   • If communication is still not possible when connecting the LEXUS hand-held tester to another vehicle, the problem is probably in the LEXUS hand-held tester itself. Consult the Service Department listed in the LEXUS hand-held tester's instruction manual in that case.
3. Check the DTC.

   HINT:

   If a malfunction occurs in the speed sensor or in the stop light switch, etc. during cruise control driving, the ECU actuates AUTO CANCEL of the cruise control and turns ON and OFF the CRUISE MAIN indicator light to inform the driver of a malfunction. At the same time, the malfunction is stored in memory as a diagnostic trouble code.

   Fig 4: Indicator Light Blinking Pattern

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Output DTC using SST.
   1. Turn the ignition switch to ON.
   2. Using SST, connect terminals TC and CG of the DLC3.

      SST 09843-18040

   3. Read the DTC on the CRUISE MAIN indicator light.
      Fig 5: Identifying Ignition Switch

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   HINT:

   • If the DTC is not output, inspect the cruise main indicator light circuit and the diagnosis circuit (See CRUISE MAIN Indicator Light Circuit ).
   • As an example, the blinking patterns for codes; normal are shown in the illustration.
     Fig 6: Identifying Blinking Pattern

     Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Hook up the LEXUS hand-held tester to the DLC3.
2. Monitor the ECU data by following the prompts on the tester screen.

   HINT:

   LEXUS hand-held tester has a "Snapshot" function which cords the monitored data.

   Please refer to the LEXUS hand-held tester operator's manual for further details.

   Fig 7: Identifying Hand Tool Tester

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

HINT:

According to the DATA LIST displayed by the LEXUS hand-held tester, you can read the value of the switch, the sensor and so on without parts removal. Reading the DATA LIST as a first step of troubleshooting is one of the method to shorten the labor time.

1. Connect the LEXUS hand-held tester to the DLC3.
2. Turn the ignition switch to ON.
3. According to the display on tester, read the "DATA LIST".
   Fig 8: Data List Table

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   HINT:

   "3" is OK but "1 "is NG --> ECM failure

   "1" is OK but "2" is NG --> DTC output or ECM failure

   "3" is OK but cruise indicator not turn ON --> Indicator or wire harness or ECM failure

1. The following actions will erase the DTCs and freeze frame data.
   1. LEXUS Hand-Held Tester: Operating the LEXUS hand-held tester to erase the codes.
   2. Except LEXUS Hand-Held Tester: Disconnecting the battery terminals or EFI fuse for 60 seconds or more.
2. After completing repairs, the DTC retained in memory can be cleared by removing the ECU-B fuse for 60 seconds or more with the ignition switch to OFF.
3. Check that the normal code is displayed after connecting the fuse.

1. Inspect the SET switch.
   1. Push the main switch button to ON.
   2. Drive at a desired speed (40 km/h (25 mph) or higher).
   3. Press the control switch to the SET/COAST.
   4. After releasing the switch, check that the vehicle cruises at the desired speed.
      Fig 9: Identifying SET Switch

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Inspect the ACCEL switch.
   1. Push the main switch button to ON.
   2. Drive at a desired speed (40 km/h (25 mph) or higher).
   3. Check that the vehicle speed increases while the control switch is turned to RES/ACC, and that the vehicle cruises at the set speed when the switch is released.
   4. Momentarily press the control switch upward in the RES/ACC and then immediately release it. Check that the vehicle speed increases by about 1.5 km/h (Tap-up function).
      Fig 10: Identifying ACCEL Switch

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Inspect the COAST switch.
   1. Push the main switch button to ON.
   2. Drive at a desired speed (40 km/h (25 mph) or higher).
   3. Check that the vehicle speed decreases while the control switch is turned to SET/COAST, and the vehicle cruises at the set speed when the switch is released.
   4. Momentarily press the control switch is turned to SET/COAST, and then immediately release it. Check that the vehicle speed decreases by about 1.5 km/h (Tap-down function).
      Fig 11: Identifying COAST Switch

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Inspect the CANCEL switch.
   1. Push the main switch button 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 OFF
      • Pull the cruise control switch to CANCEL
        Fig 12: Identifying CANCEL Switch

        Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Inspect the RESUME switch.
   1. Push the main switch button 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
      • Pull the cruise control switch to CANCEL
   4. After the control switch is turned to RES/ACC at the driving speed of more than 40 km/h (25 mph), check that the vehicle restores the speed prior to the cancellation.
      Fig 13: Identifying RESUME Switch

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Connect the LEXUS hand-held tester to the DLC3
2. Check the control switch (MAIN, CANCEL, SET/COA RES/ACC).
   Fig 14: Checking The Cruise Control Switch

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002