Electronic Modulated Suspension & Rear Air Suspension System - Diagnosis: Pre-Check

DIAGNOSIS SYSTEM
1. Inspect the battery voltage.
  Battery voltage: 11 to 14 V
  
  If voltage is below 11 V, recharge the battery before proceeding.
2. Check DLC3.
  The vehicle's suspension control ECU uses ISO 9141-2 for communication. The terminal arrangement of DLC3 complies with SAE J1962 and matches the ISO 9141-2 format.
  
  Verify conditions listed in table below:
  
  Fig 1: Checking DLC3
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 2: Terminal Specification
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  HINT:
  
  If the hand-held tester display shows UNABLE TO CONNECT TO VEHICLE when the cable of the hand-held tester is connected to DLC3, the ignition switch is turned to ON and the tester is operated, there is a problem on the vehicle side or test a side.
  - If communication is normal when the tester is connected to another vehicle, inspect 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 tester itself, so consult the Service Department listed in the tester's instruction manual.
3. Check the indicator lamp.
  1. Turn the ignition switch ON.
  2. Check that the height control OFF indicator lamp and the height control indicator lamp come on for 2 sec.
  If the indicator check result is not normal, proceed to troubleshooting for the height control indicator lamp circuit (See HEIGHT CONTROL INDICATOR LAMP CIRCUIT ) and the height control OFF indicator lamp circuit (See HEIGHT CONTROL OFF INDICATOR LAMP CIRCUIT ).
  
  Fig 3: Checking Height Control Off Indicator Lamp
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
DTC CHECK (USING SST CHECK WIRE)
1. Checking DTCs using a SST check wire.
  SST 09843-18040
  1. Using the SST, connect terminals TC and CG of DLC3.
  2. Turn the ignition switch ON.
    
    Fig 4: Connecting Terminals TC And CG Of DLC3
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Read and record any DTCs from the height control OFF indicator lamp on the combination meter. Refer to the chart on the left for examples of a normal code and codes 13 and 33.
    HINT:
    - If the height control OFF indicator lamp does not blink any DTC codes or the normal code, inspect the height control OFF indicator lamp circuit (See HEIGHT CONTROL OFF INDICATOR LAMP CIRCUIT ) and the TC terminal circuit (See TC TERMINAL CIRCUIT ).
    - If 2 or more malfunctions are indicated at the same time, the lowest numbered DTC is displayed first.
  4. Refer to the Diagnostic Trouble Code Chart (See DIAGNOSTIC TROUBLE CODE CHART ) for DTC information.
  5. After completing the check, remove SST check wire from DLC3.
    SST 09843-18040
    
    Fig 5: Checking Height Control Off Indicator Lamp
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    
    Fig 6: Examples Of A Normal Code And Codes 13 And 33
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Clearing the DTCs using the SST check wire.
  SST 09843-18040
  1. Using SST, connect terminals TC and CG of DLC3.
  2. Turn the ignition switch ON.
    
    Fig 7: Connecting Terminals TC And CG Of DLC3
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Clear DTC stored in ECU by depressing the brake pedal 8 times or more within 5 sec.
  4. Check that the height control OFF indicator lamp shows the normal code.
  5. Remove SST check wire from DLC3.
    SST 09843-18040
  HINT:
  
  Disconnect the battery cable during the operation will not erase DTC in ECU.
  
  Fig 8: Depressing Brake Pedal
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
DTC CHECK (USING HAND-HELD TESTER)
1. Checking DTCs using the Hand-held tester.
  1. Connect the hand-held tester to DLC3.
  2. Turn the ignition switch ON.
  3. Read DTCs by following the prompts on the tester screen.
    
    Fig 9: Connecting Hand-Held Tester To DLC3
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  HINT:
  
  Refer to the hand-held tester operator's manual for further details.
2. Clearing the DTCs using the Hand-held tester.
  1. Connect the hand-held tester to DLC3
  2. Turn the ignition switch ON.
  3. Erase the DTCs following the prompts on the tester screen.
  HINT:
  
  Refer to the hand-held tester operator's manual for further details.
DATA LIST
HINT:

By accessing the DATA LIST displayed by the hand-held tester, you can read the value of the switches and sensors and so on without removing any parts. Reading the DATA LIST is the first step of troubleshooting and is one method to shorten labor time.
1. Connect the hand-held tester to DLC3.
2. Turn the ignition switch ON.
3. Following the display on the tester, read the "DATA LIST".
  
  Fig 10: Display On Tester DATA List (1 Of 2)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 11: Display On Tester DATA List (2 Of 2)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
ACTIVE TEST LIST
HINT:

Perform the ACTIVE TEST using the hand-held tester to operate the sensors, relay and solenoid without removing any parts. Performing the ACTIVE TEST is the first step of troubleshooting is one of the methods to shorten labor time. It is possible to display the DATA LIST during the ACTIVE TEST.
1. Connect the hand-held tester to DLC3.
2. Turn the ignition switch ON.
3. Following the display on tester, perform the "ACTIVE TEST".
  
  Fig 12: Display On Tester ACTIVE TEST List
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INPUT SIGNAL CHECK (TEST MODE CHECK)
HINT:

This function checks that whether signals from the stop lamp switch assy and the door courtesy switch, etc. are being input normally to the ECU.
1. Procedure for Input Signal Check Mode (Test Mode) using SST check wire.
  SST 09843-18040
  1. Make sure the ignition switch is OFF.
  2. Set each of the check items in the table below to the condition in Operation (A).
  3. Using SST, connect the terminals TS and CG of DLC3.
  4. Turn the ignition switch ON.
    
    Fig 13: Connecting Terminals TS And CG Of DLC3
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. Check that the height control OFF indicator lamp is blinking.
    HINT:
    - At this time, the height control OFF indicator lamp blinks at 0.125 sec. intervals.
    - If the height control OFF indicator lamp does not blink, inspect the height control OFF indicator lamp circuit (See HEIGHT CONTROL OFF INDICATOR LAMP CIRCUIT ) and the TS terminal circuit (See TS TERMINAL CIRCUIT ).
  6. Set each of the check items to the condition in Operation (B).
    
    Fig 14: Checking Height Control Off Indicator Lamp Is Blinking
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    
    HINT:
    
    When checking each item, the height control OFF indicator lamp should come on for 1 sec.
    
    Fig 15: Check Item Specification (1 Of 2)
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    
    Fig 16: Check Item Specification (2 Of 2)
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  7. Using SST, connect the 3rd terminal of the SST check wire to terminal TC in DLC3.
    SST 09843-18040
    
    Fig 17: Connecting 3Rd Terminal Of SST Check Wire To Terminal TC In DLC3
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  8. Read the number of blinks of the height control OFF indicator lamp.
    HINT:
    - As an example, the blinking patterns of normal code and code 82 are shown in the illustration.
    - If 2 or more malfunctions are indicated at the same time, the lowest numbered code is displayed first.
    - When DTC is not output, check the TC terminal circuit TC TERMINAL CIRCUIT .
      
      Fig 18: Reading Number Of Blinks Of Height Control Off Indicator Lamp
      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  9. Check the malfunction using the code table on the next page.
    
    Fig 19: Identifying Input Signal Check Mode (Test Mode)
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Ending the Input Signal Check Mode (Test Mode) using SST check wire.
  SST 09843-18040
  1. With the ignition switch to OFF, disconnect the SST check wire from the terminals of DLC3 and then turn the ignition switch ON.
3. Procedure for Sensor Test Mode (Test Mode) using the hand-held tester.
  1. Make sure the ignition switch OFF.
  2. Set each of the check items to the condition in Operation (A) on the previous page.
  3. Connect the hand-held tester to DLC3.
  4. Turn the ignition switch ON.
  5. Select the SIGNAL CHECK mode on the hand-held tester.
  6. Set each of the check items to the condition in Operation (B) on the previous page.
    HINT:
    
    In step (6), all signals can be checked together.
  7. Read the DTCs by following the prompts on the tester screen.
  HINT:
  
  Refer to the hand-held tester operator's manual for further details.
  
  DTC from input signal check
  
  If a malfunction code is displayed during the test mode DTC check, check the circuit listed for that code. For details of each code, refer to DTC No." in the chart.
  
  Fig 20: DTC From Input Signal Check Specification (1 Of 2)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  Fig 21: DTC From Input Signal Check Specification (2 Of 2)
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
CHECK DAMPING FORCE CONTROLLING CONDITION (USING SST CHECK WIRE)
1. Checking the damping force controlling condition using the SST check wire.
  SST 09843-18040
  1. Using SST, connect terminals TS and CG of DLC3 with the ignition switch at OFF (Test Mode).
  2. Start the engine.
    Under this condition, the absorber control actuator position is 1 (Soft).
  3. Starting from the above mentioned position, as the brake pedal is depressed, the absorber control actuator position increases (1 --> 2 --> 3 --> ... 15 --> 16). At this time, bounce the vehicle and check that the shock absorber becomes harder.
    
    Fig 22: Connecting Terminals TS And CG Of DLC3 With Ignition Switch At Off (Test Mode)
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  HINT:
  - To hold the absorber control actuator at a specific position, adjust it to the position using the above mentioned procedure, and then increase the vehicle speed to over 5 km/h.
    After that speed is reached, the absorber control actuator position does not change until the ignition switch is turned to OFF.
  - If the absorber control actuator does not operate, inspect the absorber control actuator circuit and the suspension control ECU.
FAIL-SAFE FUNCTION
1. In the normal control operation, if there is short or open in the sensors, actuators, etc., the suspension control ECU suspends the damping force control operation and the vehicle height control operation.