Adaptive Variable Suspension System (Diagnostics - Introduction): Diagnosis Lexus GS IV

HOW TO PROCEED WITH TROUBLESHOOTING [03/2012 - ]

HINT

Use these procedures to troubleshoot the adaptive variable suspension system.

*: Use the Techstream.

1. VEHICLE BROUGHT TO WORKSHOP NEXT: Go to next step
2. PROBLEM SYMPTOM CONFIRMATION NEXT: Go to next step
3. INSPECT BATTERY VOLTAGE Standard voltage 11 to 14 V If the voltage is below 11 V, recharge or replace the battery before proceeding. NEXT: Go to next step
4. CHECK ECUS CONNECTED TO CAN BUS* Check the ECUs connected to the CAN bus. Refer to «DIAGNOSIS SYSTEM [03/2012 - ]»(ref-600620-S06280412312014022400000) . RESULT Result Proceed to No malfunction appears A Malfunction appears B B --> GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING). Refer to «HOW TO PROCEED WITH TROUBLESHOOTING [03/2012 - ]»(ref-600588-S38298476802014022400000) A: Go to next step
5. CHECK FOR DTC (ADAPTIVE VARIABLE SUSPENSION SYSTEM)* Check for DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600439-S15340138032014022400000) . RESULT Result Proceed to DTC is not output A DTC is output B B --> GO TO DIAGNOSTIC TROUBLE CODE CHART. Refer to «DIAGNOSTIC TROUBLE CODE CHART [03/2012 - ]»(ref-600439-S01865027742014022400000) A: Go to next step
6. PROBLEM SYMPTOM TABLE RESULT Result Proceed to Fault is not listed in problem symptoms table A Fault is listed in problem symptoms table B B --> Go to step 9 A: Go to next step
7. OVERALL ANALYSIS AND TROUBLESHOOTING* Data List / Active Test. Refer to «DATA LIST / ACTIVE TEST [03/2012 - ]»(ref-600439-S10820339722014022400000) Terminals of ECU. Refer to «TERMINALS OF ECU [03/2012 - ]»(ref-600439-S16403189122014022400000) NEXT: Go to next step
8. REPAIR OR REPLACE NEXT: Go to next step
9. CONFIRMATION TEST NEXT --> END

Scheme 1

Scheme 2

Scheme 3

1. CHECK ABSORBER CONTROL ACTUATOR OPERATION Using SST, connect the terminals 12 (TS) and 4 (CG) of the DLC3. SST: 09843-18040 Turn the power switch on (IG). Check that the "SPORT S+" indicator in the multi-information display is blinking in the Test Mode blinking pattern. HINT: If the "SPORT S+" indicator in the multi-information display does not blink, inspect the "SPORT S+" indicator. Refer to «DIAGNOSIS SYSTEM [03/2012 - ]»(ref-600439-S19860584002014022400000) . TEXT IN ILLUSTRATION *a Blinking Pattern in Test Mode *b 0.125 Seconds Check absorber control actuator operation. Starting from the SOFT position, depress the brake pedal. Using Techstream, check that the absorber control actuator position increases by 2 steps each time the brake pedal is depressed (1 (SOFT) --> 3 --> 5 --> 7 --> 9 --> 11 --> 15 --> 17 (HARD)). At this time, bounce the vehicle and check that the shock absorber is becoming harder. HINT: Every time the brake pedal is depressed, the absorber control actuator rotates in the hard to soft direction in 15° intervals up to a maximum angle of 120°. If the absorber control actuator does not operate, inspect the absorber control actuator circuit and absorber control actuator installation condition. Trouble Area See procedure Absorber control actuator circuit Refer to «DTC C1731: Front Damping Force Control Actuator RH Circuit Malfunction; DTC C1732: Front Damping Force Control Actuator LH Circuit Malfunction; DTC C1733: Rear Damping Force Control Actuator RH Circuit Malfunction; DTC C1734: Rear Damping Force Control Actuator LH Circuit Malfunction»(ref-600636-S14596684452014022400000) Front absorber control actuator installation condition Refer to «INSTALLATION [03/2012 - ]»(ref-600637-S26148668942014022400000) Rear absorber control actuator installation condition Refer to «INSTALLATION [03/2012 - ]»(ref-600637-S41051594262014022400000) TEXT IN ILLUSTRATION *a Shift Range *b 15° *c 120° *d SOFT *e HARD Turn the power switch off. Disconnect SST from terminals 12 (TS) and 4 (CG) of the DLC3. Turn the power switch on (IG). HINT: If the power switch remains on (IG) after SST is removed from DLC3, the vehicle will remain in the previously initialized Test Mode.

TEST MODE PROCEDURE [03/2012 - ]

1. TEST MODE PROCEDURE NOTE: After replacing the absorber control ECU, it is necessary to perform registration of vehicle identification information. Vehicle identification information is automatically acquired when the system enters test mode. When vehicle identification information has not been acquired, the "SPORT S+" indicator in the multi-information display blinks at 1-second intervals (1 second on and 1 second off). After vehicle identification information is acquired, the "SPORT S+" indicator in the multi-information display blinks at 0.125-second intervals (0.125 seconds on and 0.125 seconds off). HINT: When entering test mode, the absorber control ECU stores all the test mode DTCs first. After completing the check for each test mode item, the test mode DTCs whose deletion conditions are met are cleared. The test mode DTCs for some items may not be cleared when only a certain signal is inspected. When the system returns to normal mode, all the test mode DTCs will be cleared. Turn the power switch off. Connect the Techstream to the DLC3. Turn the power switch on (IG). Turn the Techstream on. Enter the following menus: Chassis / Air suspension / Utility / Signal Check. Confirm that the system is in test mode by checking that the "SPORT S+" indicator in the multi-information display blinks at 0.125-second intervals (0.125 seconds on and 0.125 seconds off). Read the test mode DTCs by following the prompts on the Techstream screen. After completing test mode, disconnect the Techstream and turn the power switch off.
2. TEST MODE DTC CHART HINT: When entering test mode, the absorber control ECU stores all the test mode DTCs. If the deletion conditions for a test mode DTC are met, it is cleared. If a trouble code is output during the test mode DTC check, check the circuit listed for that code. For details of each code, refer to the "See" for the respective DTC in the chart. DTC Code Detection Item Trouble Area Deletion Condition See C1796 Front acceleration sensor RH circuit malfunction Absorber control ECU (houses front acceleration sensor RH) The vehicle is stationary on a level surface and an acceleration sensor value that is within -1.96 to 1.96 m/s 2 is received from the acceleration sensor for 1 second or more. Refer to «DTC C1715: Front Acceleration Sensor RH Malfunction; DTC C1716: Front Acceleration Sensor LH Malfunction; DTC C1717: Rear Acceleration Sensor Malfunction; DTC C1796: Front Acceleration Sensor RH Malfunction (Test Mode DTC); DTC C1797: Front Acceleration Sensor LH Malfunction (Test Mode DTC); DTC C1798: Rear Acceleration Sensor Malfunction (Test Mode DTC)»(ref-600636-S27033949762014022400000) C1797 Front acceleration sensor LH circuit malfunction Front acceleration sensor LH Front acceleration sensor LH circuit Absorber control ECU C1798 Rear acceleration sensor circuit malfunction Rear acceleration sensor Rear acceleration sensor circuit Absorber control ECU

PROBLEM SYMPTOMS TABLE [03/2012 - ]

HINT

1. Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.
2. Inspect the fuses and relays related to this system before inspecting the suspected areas below.

ADAPTIVE VARIABLE SUSPENSION SYSTEM

Scheme 4

1. CHECK ABSORBER CONTROL ECU TEXT IN ILLUSTRATION *a Component with harness connected (Absorber Control ECU) - - HINT: Inspect the connectors from the back side while the connectors are connected. Check the operation of a particular valve by listening for operating sounds or by using the Data List. Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition A37-9 (SBL3) - Body ground R Front acceleration sensor LH power source Power switch on (IG) 4.75 to 5.25 V A37-10 (SGL3) - Body ground BR Front acceleration sensor LH ground Always Below 1 ohms A37-18 (SGFL) - Body ground LG Front acceleration sensor LH Power switch on (IG) 0 to 5 V N105-3 (B) - Body ground B IG power supply Power switch on (IG) 11 to 14 V N105-5 (GND) - Body ground W-B Ground Always Below 1 ohms N105-7 (CANH) - N105-8 (CANL) G - LG CAN communication line Power switch off 54 to 69 ohms N105-16 (SGR3) - Body ground LG Rear acceleration sensor ground Always Below 1 ohms N105-17 (SBR3) - Body ground BR Rear acceleration sensor power source Power switch on (IG) 4.75 to 5.25 V N105-26 (SGRR) - Body ground Y Rear acceleration sensor Power switch on (IG) 0 to 5 V

DIAGNOSIS SYSTEM [03/2012 - ]

1. DIAGNOSIS SYSTEM DTCs (normal mode) DTCs are stored in the absorber control ECU and output by using the Techstream. Refer to the DTC check procedure. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600439-S15340138032014022400000) . Test mode By switching from normal mode to test mode, it is possible to inspect the front acceleration sensor and rear acceleration sensor. Refer to «TEST MODE PROCEDURE [03/2012 - ]»(ref-600439-S13383850182014022400000) .
2. CHECK INDICATOR LIGHT Turn the power switch on (IG). Check that the "SPORT S+" indicator in the multi-information display is displayed for approximately 1.5 seconds after the combination meter initialization. If the indicator check result is not normal, proceed to troubleshooting for the indicator. Refer to «PROBLEM SYMPTOMS TABLE [03/2012 - ]»(ref-600439-S39927517902014022400000) .

DTC CHECK / CLEAR [03/2012 - ]

1. CHECK FOR DTC Turn the power switch off. Connect the Techstream to the DLC3. Turn the power switch on (IG). Turn the Techstream on. Enter the following menus: Chassis / Air suspension / Trouble Codes. Read the DTCs by following the prompts on the tester screen. HINT: Refer to the Techstream operator's manual for further details. Refer to "Diagnostic Trouble Code Chart" for DTC information. Refer to «DIAGNOSTIC TROUBLE CODE CHART [03/2012 - ]»(ref-600439-S01865027742014022400000) .
2. CLEAR DTC HINT: After repairing the malfunctions, clear the DTCs. Turn the power switch off. Connect the Techstream to the DLC3. Turn the power switch on (IG). Turn the Techstream on. Enter the following menus: Chassis / Air suspension / Trouble Codes. Clear the DTCs by following the prompts on the Techstream screen. HINT: Refer to the Techstream operator's manual for further details.

DATA LIST / ACTIVE TEST [03/2012 - ]

1. READ DATA LIST HINT: Using the Techstream to read the Data List allows the values or states of switches, sensors, actuators and other items to be read without removing any parts. This non-intrusive inspection can be very useful because intermittent conditions or signals may be discovered before parts or wiring is disturbed. Reading the Data List information early in troubleshooting is one way to save diagnostic time. NOTE: In the table below, the values listed under "Normal Condition" are reference values. Do not depend solely on these reference values when deciding whether a part is faulty or not. Warm up the engine. Turn the power switch off. Connect the Techstream to the DLC3. Turn the power switch on (IG). Turn the Techstream on. Enter the following menus: Chassis / Air suspension / Data List. According to the display on the Techstream, read the Data List. AIR SUSPENSION Tester Display Measurement Item/Range Normal Condition Diagnostic Note (Up&Down)G Sensor FR Front acceleration sensor RH (up and down)/ Min.: -1045.29 m/s 2 Max.: 1045.26 m/s 2 -0.98 to 0.98 m/s 2 when stationary The value changes when the vehicle (front RH) is bounced. (Up&Down)G Sensor FL Front acceleration sensor LH (up and down)/ Min.: -1045.29 m/s 2 Max.: 1045.26 m/s 2 -0.98 to 0.98 m/s 2 when stationary The value changes when the vehicle (front LH) is bounced. (Up&Down)G Sensor Rear Rear acceleration sensor (up and down)/ Min.: -1045.29 m/s 2 Max.: 1045.26 m/s 2 -0.98 to 0.98 m/s 2 when stationary The value changes when the vehicle (rear) is bounced. Gravity Sensor(Side to Side) Acceleration sensor (side to side)/ Min.: -1176.37 m/s 2 Max.: 1176.33 m/s 2 Changes depending on acceleration generated when turning - Stop Light Switch Stop light switch/ ON or OFF ON: Brake pedal depressed OFF: Brake pedal released - SPORT Switch Drive mode select switch/ ON or OFF ON: SPORT S+ mode OFF: Not in SPORT S+ mode - HV Ready HV ready/ ON or OFF ON: Ready on OFF: Ready off - TC Terminal TC terminal/ ON or OFF ON: DTC output OFF: DTC not output - TS Terminal TS terminal/ ON or OFF ON: During test mode OFF: During normal mode - IG Power Source Voltage ECU power supply voltage/ Min.: 0.0 V Max.: 25.5 V 11 to 14 V (Actual ECU power supply voltage): Power switch on (IG) - Steering Angle Steering sensor reading/ Min.: -49152.0 deg Max.: 49150.5 deg Actual steering angle Steering wheel turned left: reading increases Steering wheel turned right: reading decreases - FR Wheel Speed Front speed sensor RH reading/ Min.: 0 km/h (0 mph) Max.: 255 km/h (159 mph) Actual vehicle speed No large fluctuations when driving at a constant speed. FL Wheel Speed Front speed sensor LH reading/ Min.: 0 km/h (0 mph) Max.: 255 km/h (159 mph) Actual vehicle speed No large fluctuations when driving at a constant speed. RR Wheel Speed Rear speed sensor RH reading/ Min.: 0 km/h (0 mph) Max.: 255 km/h (159 mph) Actual vehicle speed No large fluctuations when driving at a constant speed. RL Wheel Speed Rear speed sensor LH reading/ Min.: 0 km/h (0 mph) Max.: 255 km/h (159 mph) Actual vehicle speed No large fluctuations when driving at a constant speed. Driving Torque Driving torque/ Min.: -1024 Nm Max.: 1023 Nm - - Damper Step FR Damper step (front RH)/ Min.: 1 step Max.: 255 step 1 to 17 step - Damper Step FL Damper step (front LH)/ Min.: 1 step Max.: 255 step 1 to 17 step - Damper Step RR Damper step (rear RH)/ Min.: 1 step Max.: 255 step 1 to 17 step - Damper Step RL Damper step (rear LH)/ Min.: 1 step Max.: 255 step 1 to 17 step - Max Damper Step FR Max. damper step (front RH)/ Min.: 0 step Max.: 255 step 17 step - Max Damper Step FL Max. damper step (front LH)/ Min.: 0 step Max.: 255 step 17 step - Max Damper Step RR Max. damper step (rear RH)/ Min.: 0 step Max.: 255 step 17 step - Max Damper Step RL Max. damper step (rear LH)/ Min.: 0 step Max.: 255 step 17 step - Adaptive Variable Suspension(AVS) Mode Adaptive variable suspension system (AVS) mode/ NORMAL, COMFORT, SEMI CO, SEMI SP or SPORTS NORMAL: Not in SPORT S+ mode SPORTS: SPORT S+ mode - Compatible Constant Information Information used to change the compatible constant Min.: 0 Max.: 255 - - Identical Constant Information Information used to change the identical constant Min.: 0 Max.: 255 - - Design Constant Information Information used to change the design constant Min.: 0 Max.: 255 - - AVS Control Information FR AVS control information (front wheel RH) Min.: 0 Max.: 255 - - AVS Control Information FL AVS control information (front wheel LH) Min.: 0 Max.: 255 - - AVS Control Information RR AVS control information (rear wheel RH) Min.: 0 Max.: 255 - - AVS Control Information RL AVS control information (rear wheel LH) Min.: 0 Max.: 255 - - Number of Trouble Codes Number of DTCs stored/ Min.: 0 Max.: 255 0
2. PERFORM ACTIVE TEST HINT: Using the Techstream to perform Active Tests allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Tests early in troubleshooting is one way to save diagnosis time. Data List information can be displayed while performing Active Tests. Warm up the engine. Turn the power switch off. Connect the Techstream to the DLC3. Turn the power switch on (IG). Turn the Techstream on. Enter the following menus: Chassis / Air suspension / Active Test. According to the display on the Techstream, perform the Active Test. AIR SUSPENSION Tester Display Test Part Control Range Diagnostic Note Damper Step FR Changes damper step (front RH) 1 to 17 Step The shock absorber hardens as the damper step increases. Damper Step FL Changes damper step (front LH) 1 to 17 Step The shock absorber hardens as the damper step increases. Damper Step RR Changes damper step (rear RH) 1 to 17 Step The shock absorber hardens as the damper step increases. Damper Step RL Changes damper step (rear LH) 1 to 17 Step The shock absorber hardens as the damper step increases.

DIAGNOSTIC TROUBLE CODE CHART [03/2012 - ]

HINT

1. If no abnormality is found when inspecting parts, inspect the absorber control ECU and ground points for poor contact.
2. If a trouble code is output during the DTC check, check the trouble areas listed for the DTC. For details of each code, refer to the "See" for the respective DTC in the DTC chart.
3. When 2 or more DTCs are output, perform circuit inspections one by one until the problem is identified.
4. Inspect the fuses and relays before investigating the trouble areas as shown in the table below.

ADAPTIVE VARIABLE SUSPENSION SYSTEM