Section 479 (Cruise Control System - Diagnostics): Pre-Check

WARNING: This page is about a different car, the 2004 Toyota RAV4. However, it is still accessible from the selected car via links, so may be relevant.

DIAGNOSIS SYSTEM
1. Description
  The ECM controls the cruise control function on this vehicle. Data of the cruise control or DTC can be read from the DLC3 of the vehicle. When cruise control function is malfunctioning the CRUISE main indicator does not light up but DTC inspection is performed.
  
  Therefore, when the cruise control function seems to have a malfunction, use the hand-held tester or SST to check and troubleshoot it.
  
  Fig 1: Checking DLC3 By Hand-Held Tester
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the DLC3.
  The vehicle's ECM uses the ISO 9141-2 for communication. The terminal arrangement of the DLC3 complies with the SAE J1962 and matches the ISO 9141-2 format.
  
  Fig 2: Identifying Terminals Of DLC3 Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 3: DLC3 Specified Condition Table
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  HINT:
  
  If the display shows "UNABLE TO CONNECT TO VEHICLE" when you have connected the cable of the hand-held tester to the DLC3, turned the ignition switch ON and operated the hand-held tester, there is a problem on the vehicle side or tester side.
  - If the communication is normal when the tester is connected to another vehicle, inspect the DLC3 on the original vehicle.
  - If the communication is still impossible when the tester is connected to another vehicle, the problem is probably in the tester itself. Consult the Service Department listed in the tester's instruction manual.
3. Check the indicator.
  1. Turn the ignition switch ON.
  2. Check that the CRUISE main indicator turns on when the cruise control main switch is turned ON, and that the indicator light turns off when the main switch is turned OFF.
    
    Fig 4: Locating Cruise Main Indicator
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    
    HINT:
    
    If the indicator check result is not as specified, proceed to troubleshooting for the combination meter section (see PROBLEM SYMPTOMS TABLE ).
4. Check the DTC.
  HINT:
  
  If a malfunction occurs in the speed sensor or actuator, etc. during cruise control driving, the ECM 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 the memory as a DTC.
  
  Fig 5: Locating Indicator Light ON-OFF
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Output a DTC using diagnosis check wire.
  1. Turn the ignition switch 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.
  HINT:
  - If a DTC is not output, inspect the diagnosis circuit.
  - As an example, the blinking patterns for codes; normal and 52 are shown in Fig 7.
    
    Fig 7: Locating DTC Normal Code & Malfunction Code 52
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
MONITOR ECM DATA BY USING HAND-HELD TESTER
1. Connect the hand-held tester to the DLC3.
2. Monitor the ECM data by following the prompts on the tester screen.
  HINT:
  
  The hand-held tester has a "Snapshot" function which records the monitored data.
  
  Please refer to the hand-held tester operator's manual for further details.
DATA LIST
HINT:

According to 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 a first step of troubleshooting is one of the method to shorten the labor time.
1. Connect the hand-held to the DLC3.
2. Turn the ignition switch ON.
3. Read the "DATA LIST" on the tester.
  
  Fig 9: Data List Table (1 Of 2)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 10: Data List Table (2 Of 2)
  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 does not turn on --> Indicator or wire harness or ECM failure
DTC CLEARANCE
1. The following actions will erase DTCs and freeze frame data.
  1. Operating the hand-held tester to erase the codes (see the instruction manual for the hand-held tester).
  2. Disconnecting the battery terminals or EFI1 fuse.
2. After completing repairs, the DTC retained in the memory can be cleared by removing the ECU-B fuse for 10 seconds 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 ON.
  2. Drive at the set speed (40 km/h (25 mph) or higher).
  3. Press the control switch downward for the -/SET.
  4. Release the switch, and check that the vehicle cruises at the set speed.
    
    Fig 11: Inspecting SET Switch
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Inspect the ACCEL switch.
  1. Push the main switch ON.
  2. Drive at the set speed (40 km/h (25 mph) or higher).
  3. Check that the vehicle speed increases while the control switch is turned to +/RES, and that the vehicle cruises at the set speed when the switch is released.
    
    Fig 12: Inspecting ACCEL Switch
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. Momentarily push the control switch upward in the +/RES direction and then immediately release it. Check that the vehicle speed increases by about 1.5 km/h (0.9 mph) (tap-up function).
3. Inspect the COAST switch.
  1. Push the main switch ON.
  2. Drive at the set speed (40 km/h (25 mph) or higher).
  3. Check that the vehicle speed decreases while the control switch is turned to -/SET, and the vehicle cruises at the set speed when the switch is released.
  4. Momentarily push the control switch downward for the -/SET, and then immediately release it. Check that the vehicle speed decreases by about 1.5 km/h (0.9 mph) (tap-down function).
    
    Fig 13: Inspecting COAST Switch
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Inspect the CANCEL switch.
  1. Push the main switch ON.
  2. Drive at the set 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 into any positions except the D position.
    - Push the main switch OFF.
    - Pull the cruise control switch for CANCEL.
      
      Fig 14: Inspecting CANCEL Switch
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
5. Inspect the RESUME switch.
  1. Push the main switch ON.
  2. Drive at the set 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 into any positions except the D position.
    - Pull the cruise control switch for CANCEL.
      
      Fig 15: Inspecting RESUME Switch
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. Turn the control switch to +/RES at the driving speed of more than 40 km/h (25 mph), and check that the vehicle restores the speed before the cancellation.
INPUT SIGNAL CHECK BY USING HAND-HELD TESTER
1. Connect the hand-held tester to the DLC3.
2. Check the control switches (ON-OFF, CANCEL, -/SET, +/RES).
  
  Fig 16: Checking Control Switches
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002