Occupant Classification System (Diagnostics - Introduction): Diagnosis Lexus GS III рестайлинг

HOW TO PROCEED WITH TROUBLESHOOTING

HINT

*: Use the Techstream.

1. VEHICLE BROUGHT TO WORKSHOP NEXT: Go to next step
2. CUSTOMER PROBLEM ANALYSIS Confirm problem symptoms. Refer to «PROBLEM SYMPTOMS TABLE»(ref-386978-S37589423862011022400000) . NEXT: Go to next step
3. PASSENGER AIRBAG ON/OFF INDICATOR CHECK NEXT: Go to next step
4. DTC FOR CHECK (Present and Past DTC)* Check for DTCs. Refer to «DTC CHECK / CLEAR»(ref-386978-S38054453392011022400000) . RESULT: Result Proceed to DTC output occurs A DTC output does not occur B B --> Go to «PROBLEM SYMPTOMS TABLE»(ref-386978-S11502268592011022400000) A: Go to next step
5. DTC CHART NEXT: Go to next step
6. CIRCUIT INSPECTION* NEXT: Go to next step
7. REPAIR NEXT: Go to next step
8. CLEAR DTC (Present and Past DTCs)* Clear DTCs. Refer to «DTC CHECK / CLEAR»(ref-386978-S38054453392011022400000) . NEXT: Go to next step
9. DTC CHECK (Present and Past DTC)* Check for DTCs. RESULT: Result Proceed to DTC output does not occur A DTC output occurs B B --> Go to step 5 A: Go to next step
10. SYMPTOM SIMULATION Check the passenger airbag ON/OFF indicator condition. Refer to «DIAGNOSIS SYSTEM»(ref-386978-S29165495202011022400000) . RESULT Result Proceed to Passenger airbag ON/OFF indicator operates normally A Passenger airbag ON/OFF indicator ("OFF") and SRS warning light come on B B --> Go to step 5 A: Go to next step
11. CONFIRMATION TEST NEXT --> END

PROBLEM SYMPTOMS TABLE

HINT

1. Use the table below to help determine the cause of the problem symptom. 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.

OCCUPANT CLASSIFICATION SYSTEM

Scheme 129

1. CHECK OCCUPANT CLASSIFICATION ECU Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition a17-5 (GND) - Body ground W-B - Body ground Occupant classification ECU ground line Always Below 1 ohms a17-6 (PS) - a17-15 (GPS) P - V Pressure sensor signal line Power switch ON (IG) Below 1 V a17-7 (VPS) - a17-5 (GND) R - W-B Pressure sensor +B line Power switch ON (IG) 4.75 to 5.25 V a17-8 (GBT) - a17-5 (GND) GR - W-B Belt tension sensor ground line Always Below 1 V a17-9 (IG) - a17-5 (GND) L - W-B Occupant classification ECU +B line Power switch ON (IG) 10 to 14 V a17-10 (DIA) - a17-5 (GND) R - W-B Diagnosis (DLC3) Power switch ON (IG) Pulse generation a17-11 (FSR+) - a17-12 (FSR-) L - P Center airbag sensor communication line Power switch ON (IG) Pulse generation a17-12 (FSR-) - a17-5 (GND) P - W-B Center airbag sensor communication line (-) Always Below 1 ohms a17-13 (BSW) - a17-14 (BGND) W - Y Passenger side buckle switch line Power switch ON (IG) Low: 4 to 7 mA Hi: 12 to 18 mA a17-14 (BGND) - a17-5 (GND) Y - W-B Passenger side buckle switch ground line Always Below 1 ohms a17-15 (GPS) - a17-5 (GND) V - W-B Pressure sensor ground line Always Below 1 ohms a17-16 (BT) - a17-5 (GND) BR - W-B Belt tension sensor signal line Power switch ON (IG) Below 1 V a17-17 (VBT) - a17-5 (GND) G - W-B Belt tension sensor +B line Power switch ON (IG) 4.75 to 5.25 V

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1. CHECK DLC3 The ECU uses ISO 15765-4 for communication. The terminal arrangement of the DLC3 complies with SAE J1962 and matches the ISO 15765-4 format. Symbols (Terminal No.) Terminal Description Condition Pulse condition SIL (7) - SG (5) Bus "+" Line During transmission Pulse generation CG (4) - Body ground Chassis Ground Always Below 1 ohms SG (5) - Body ground Signal ground Always Below 1 ohms BAT (16) - Body ground Battery positive Always 10 to 14 V CANH (6) - CANL (14) CAN bus line Power switch OFF* 54 to 69 ohms CANH (6) - BAT (16) HIGH-level CAN bus line Power switch OFF* 6 kohms or higher CANH (6) - CG (4) HIGH-level CAN bus line Power switch OFF* 200 ohms or higher CANL (14) - BAT (16) LOW-level CAN bus line Power switch OFF* 6 kohms or higher CANL (14) - CG (4) LOW-level CAN bus line Power switch OFF* 200 ohms or higher NOTE: *: Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power switch, any other switches, or the doors. If the result is not as specified, the DLC3 may have a malfunction. Repair or replace the harness and connector. HINT: Connect the cable of the Techstream to the DLC3, turn the power switch ON (IG) and attempt to use the Techstream. If the display indicates that a communication error has occurred, there is a problem either with the vehicle or with the Techstream. If communication is normal when the Techstream is connected to another vehicle, inspect the DLC3 of the original vehicle. If communication is still not possible when the Techstream is connected to another vehicle, the problem is probably in the Techstream itself. Consult the Service Department listed in the Techstream's instruction manual.
2. SYMPTOM SIMULATION HINT: The most difficult case in troubleshooting is when no symptoms occur. In such cases, a thorough customer problem analysis must be carried out. Then the same or similar conditions and the environment in which the problem occurred in the customer's vehicle should be simulated. No matter how experienced or skilled a technician may be, if he proceeds to troubleshooting without confirming the problem symptoms, he will likely overlook something important and make a wrong guess at some points in the repair operation. This leads to a standstill in troubleshooting. Vibration method: When vibration seems to be the major cause. HINT: Perform the simulation method only during the primary check period (for approximately 6 seconds after the power switch is turned ON (IG)). Slightly vibrate the part of the sensor considered to be the problem cause with your fingers and check whether the malfunction occurs. HINT: Shaking the relays too strongly may result in open relays. Slightly shake the connector vertically and horizontally. Slightly shake the wire harness vertically and horizontally. The connector joint and fulcrum of the vibration are the major areas to be checked thoroughly.
3. FUNCTION OF PASSENGER AIRBAG ON/OFF INDICATOR Initial check: Turn the power switch ON (IG). The passenger airbag ON/OFF indicator ("ON" and "OFF") comes on for approximately 4 seconds, then goes off for approximately 2 seconds. Approximately 6 seconds after the power switch is turned on (IG), the passenger airbag ON/OFF indicator will show ON or OFF depending on the conditions listed below. Condition ON Indicator OFF Indicator Vacant OFF OFF Adult is seated ON OFF Child is seated OFF ON Child restraint system is set OFF ON Occupant classification system failure OFF ON HINT: The passenger airbag ON/OFF indicator is based on the timing chart below in order to check the indicator light circuit. When the occupant classification system has trouble, both the SRS warning light and the passenger airbag ON/OFF indicator ("OFF") come on. In this case, check the DTCs in "AIRBAG SYSTEM" first.
4. CHECK PASSENGER AIRBAG ON/OFF INDICATOR Turn the power switch ON (IG). Check that the passenger airbag ON/OFF indicator ("ON" and "OFF") comes on for approximately 4 seconds, then goes off for approximately 2 seconds. HINT: Refer to the table in the previous step regarding the passenger airbag ON/OFF indicator when the power switch is turned ON (IG) and approximately 6 seconds pass. See 3 .

DTC CHECK / CLEAR

1. DTC CHECK HINT: When DTC B1650/32 is detected as a result of troubleshooting for "AIRBAG SYSTEM", perform troubleshooting for the "OCCUPANT CLASSIFICATION SYSTEM". Use the Techstream to read and clear DTCs, otherwise the DTCs cannot be read and cleared. Check for DTCs. Connect the Techstream to the DLC3. Turn the power switch ON (IG). Check the DTCs by following the prompts on the Techstream screen. HINT: Refer to the Techstream operator's manual for further details. Clear DTCs. Connect the Techstream to the DLC3. Turn the power switch ON (IG). 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

1. DATA LIST FOR OCCUPANT CLASSIFICATION ECU 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. Turn ON the Techstream. Enter the following menus: Body Electrical / Occupant Detection / Data List. According to the display on Techstream, read the "DATA LIST". OCCUPANT CLASSIFICATION ECU: Tester Display Measurement Item/Range Normal Condition Specified Condition for Zero Point Calibration Diagnostic Note Passenger Classification Passenger classification / NG, AM50, AF05, CHILD or OFF NG: Data is not determined AM50: Adult is seated and seat is in rear position AF05: Adult is seated and seat is in front position CHILD: Child is seated OFF: Vacant OFF - Passenger Buckle SW Buckle switch (passenger side) / SET, UNSET or NG SET: Passenger side seat belt is fastened UNSET: Passenger side seat belt is unfastened NG: Data is not determined UNSET - Pressure sensor output Pressure sensor output / Min.: 0, Max.: 255 0 to 210 (reference value) 0 to 2 - Filtered pressure sensor output Filtered pressure sensor output / Min.: 0, Max.: 255 38 to 240 38 to 75 If value is outside range of Specified Condition for Zero Point Calibration, check whether any objects placed on seat cushion and that seat cushion fitted correctly Thermistor temperature output Thermistor temperature output / Min.: -40°C (-40°F), Max.: 90°C (194°F) -40 to 85°C (-40 to 185°F) 3 to 40°C (36 to 104°F) If value is outside range of Specified Condition for Zero Point Calibration, adjust temperature to proper range by using air conditioner, etc. Weight threshold Weight threshold / Min.: 0, Max.: 255 36 to 67 (reference value) 36 to 67 (reference value) - Filtered belt tension output Filtered belt tension output / Min.: 0, Max.: 255 39 to 229 39 to 64 (no load) - Empty threshold value from the seat factory Empty threshold value from seat factory / Min.: 0, Max.: 255 38 to 75 38 to 75 - Allow threshold Threshold value for adult passenger or not from seat factory / Min.: 0, Max.: 255 43 to 64 (reference value) 43 to 64 (reference value) - Number of Present DTC Number of present trouble codes / Min.: 0, Max.: 255 0 0 - Number of Past DTC Number of past trouble codes / Min.: 0, Max.: 255 0 0

DIAGNOSTIC TROUBLE CODE CHART

HINT

1. When DTC B1650/32 is detected as a result of troubleshooting for the "AIRBAG SYSTEM", perform troubleshooting for the "OCCUPANT CLASSIFICATION SYSTEM" as shown in the chart below.

1. Use Techstream to read and clear the DTC of the occupant classification ECU, otherwise the DTCs cannot be read and cleared.

OCCUPANT CLASSIFICATION SYSTEM