Occupant Classification System (diagnostics - Introduction) (except Phv) Toyota Prius PHV pre-III

PRECAUTION

Note. When disconnecting the cable from the negative (-) battery terminal, initialize the following systems after the cable is reconnected. System Name See Procedure Advanced Parking Guidance System Refer to INITIALIZATION

1. GENERAL PRECAUTION Perform zero point calibration and sensitivity check if any of the following conditions occur: The occupant classification ECU is replaced. Accessories (seatback tray and seat cover, etc.) are installed. The front passenger seat is removed from the vehicle. The passenger airbag ON/OFF indicator ("OFF") comes on when the front passenger seat is not occupied. The vehicle is brought to the workshop for repair due to an accident or a collision.

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SYSTEM DESCRIPTION

1. GENERAL In the occupant classification system, the occupant classification ECU calculates the weight of the occupant based on signals from the occupant classification sensors. This system recognizes the occupant as a child if it detects a weight of less than 36 kg (79.3 lb), and disables the front passenger airbag and front seat belt pretensioner RH. This system is mainly comprised of 4 occupant classification sensors that detect the load on the front passenger seat. The occupant classification ECU controls the system, and the passenger airbag ON/OFF indicator indicates the ON/OFF condition of the front passenger airbag and front seat belt pretensioner RH.

HOW TO PROCEED WITH TROUBLESHOOTING

HINT

1. Use the following procedure to troubleshooting the occupant classification system.
2. *: 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»(/toyota/prius-phv/pre-iii-2010-2011/remont/restraints-control-systems/#occupant-classification-system-diagnostics-introduction-except-phv__problem-symptoms-table) . NEXT: Go to next step
3. PASSENGER AIRBAG ON/OFF INDICATOR CHECK NEXT: Go to next step
4. DTC CHECK (Present and History DTCs) Check for DTCs. Result Result Proceed to DTC is output. A DTC is not output. B B --> GO TO PROBLEM SYMPTOMS TABLE 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 DTCS (Present and History DTCs)* Clear the DTCs. NEXT: Go to next step
9. DTC CHECK (Present and History DTCs)* Check for DTCs. 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»(/toyota/prius-phv/pre-iii-2010-2011/remont/restraints-control-systems/#occupant-classification-system-diagnostics-introduction-except-phv__diagnostic-trouble-code-chart) A: Go to next step
10. SYMPTOM SIMULATION Check the passenger airbag ON/OFF indicator condition. 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 DIAGNOSTIC TROUBLE CODE CHART. Refer to «DIAGNOSTIC TROUBLE CODE CHART»(/toyota/prius-phv/pre-iii-2010-2011/remont/restraints-control-systems/#occupant-classification-system-diagnostics-introduction-except-phv__diagnostic-trouble-code-chart) A: Go to next step
11. CONFIRMATION TEST NEXT --> END

INITIALIZATION

Note. Make sure that the front passenger seat is not occupied before performing the operation.

HINT

Perform zero point calibration and sensitivity check if any of the following conditions occur

1. The occupant classification ECU is replaced.
2. Accessories (seatback tray and seat cover, etc.) are installed.
3. The front passenger seat is removed from the vehicle.
4. The passenger airbag ON/OFF indicator ("OFF") comes on when the front passenger seat is not occupied.
5. The vehicle is brought to the workshop for repair due to an accident or a collision.

1. ZERO POINT CALIBRATION Zero point calibration procedure HINT: Make sure that zero point calibration has finished normally, and then perform the sensitivity check. Check that all of the following conditions are met: The vehicle is parked on a level surface. No objects are placed on the front passenger seat. The front passenger seat belt buckle switch is off. Adjust the seat position according to the table below. Adjustment Item Position Slide Direction Rearmost position Reclining Angle Upright position Headrest Height Lowest position Lifter Height Lowest position 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: Body Electrical/Occupant Detection/Utility/Zero Point Calibration. Perform zero point calibration by following the prompts on the Techstream screen. HINT: Refer to the Techstream operator's manual for further details. If zero point calibration does not complete, replace the front seat cushion spring assembly. OK "Zero Point Calibration is complete." is displayed.
2. SENSITIVITY CHECK Sensitivity check procedure 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: Body Electrical/Occupant Detection/Utility/Sensitivity Check. Perform sensitivity check by following the prompts on the Techstream screen. HINT: Refer to the Techstream operator's manual for further details. Confirm that the initial sensor reading is within the specified range. Standard -3.2 to 3.2 kg (-7.0 to 7.0 lb) Place a 30 kg (66.1 lb) weight (e.g. a 30 kg (66.1 lb) of lead mass) onto the front passenger seat. Confirm that sensitivity is within the specified range. Standard 27 to 33 kg (59.5 to 72.8 lb) HINT: When performing sensitivity check, use a solid metal weight (the check result may not appear properly if a liquid weight is used). If sensitivity deviates from the specified range, retighten the bolts of the front passenger seat without deforming the seat rail. After performing this procedure, if sensitivity is not within the specified range, replace the Front seat cushion spring assembly.

PROBLEM SYMPTOMS TABLE

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.

OCCUPANT CLASSIFICATION SYSTEM

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1. OCCUPANT CLASSIFICATION ECU Terminal No. (Symbol) Wiring Color Terminal Description Condition Specification W3-1 (+B) - W3-3 (GND) W - W-B Battery Always 11 to 14 V W3-2 (DIA) - W3-3 (GND) GR - W-B Diagnosis (DLC3) Power switch on (IG) Pulse generation W3-3 (GND) - Body ground W-B - Body ground Ground Always Below 1 V W3-4 (FSR-) - W3-3 (GND) LG - W-B Center airbag sensor assembly communication line Always Below 1 V W3-5 (BGND) - W3-3 (GND) P - W-B Passenger side buckle switch ground line Always Below 1 V W3-7 (IG) - W3-3 (GND) B - W-B Power source Power switch on (IG) 11 to 14 V W3-8 (FSR+) - W3-4 (FSR-) L - LG Center airbag sensor assembly communication line Power switch on (IG) Pulse generation W3-9 (BSW) - W3-5 (BGND) G - P Passenger side buckle switch line Always Pulse generation W2-1 (SGD1) - W3-3 (GND) G - W-B Front occupant classification sensor LH ground line Always Below 1 V W2-2 (SGD2) - W3-3 (GND) LG - W-B Front occupant classification sensor RH ground line Always Below 1 V W2-3 (SGD3) - W3-3 (GND) W - W-B Rear occupant classification sensor LH ground line Always Below 1 V W2-4 (SGD4) - W3-3 (GND) BR - W-B Rear occupant classification sensor RH ground line Always Below 1 V W2-5 (SVC3) - W2-3 (SGD3) GR - W Rear occupant classification sensor LH power supply line Power switch on (IG) 4.9 to 5.1 V W2-6 (SVC4) - W2-4 (SGD4) V - BR Rear occupant classification sensor RH power supply line Power switch on (IG) 4.9 to 5.1 V W2-7 (SIG1) - W2-1 (SGD1) P - G Front occupant classification sensor LH signal line Power switch on (IG), a load applied to front occupant classification sensor LH 0 to 5.1 V W2-8 (SIG2) - W2-2 (SGD2) L - LG Front occupant classification sensor RH signal line Power switch on (IG), a load applied to front occupant classification sensor RH 0 to 5.1 V W2-9 (SIG3) - W2-3 (SGD3) SB - W Rear occupant classification sensor LH signal line Power switch on (IG), a load applied to rear occupant classification sensor LH 0 to 5.1 V W2-10 (SIG4) - W2-4 (SGD4) B - BR Rear occupant classification sensor RH signal line Power switch on (IG), a load applied to rear occupant classification sensor RH 0 to 5.1 V W2-11 (SVC1) - W2-1 (SGD1) R - G Front occupant classification sensor LH power supply line Power switch on (IG) 4.9 to 5.1 V W2-12 (SVC2) - W2-2 (SGD2) W - LG Front occupant classification sensor RH power supply line Power switch on (IG) 4.9 to 5.1 V

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1. CHECK DLC3 Check the DLC3. Refer to «GENERAL INFORMATION»(/toyota/prius-phv/pre-iii-2010-2011/remont/hoistjack/#introduction-except-phv) .
2. 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 indicate ON or OFF depending on the conditions listed below. Front Passenger Seat Condition Passenger Airbag ON/OFF Indicator SRS Warning Light ON Indicator OFF Indicator Vacant OFF OFF OFF Adult is seated. ON OFF OFF Child is seated. OFF ON OFF Child restraint system is set. OFF ON OFF Occupant classification system failure OFF ON ON HINT: The passenger airbag ON/OFF indicator illuminates 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 passenger airbag ON/OFF indicator ("OFF") come on. In this case, check the DTCs in the airbag system first.
3. 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 previous step regarding the passenger airbag ON/OFF indicator when the power switch is turned on (IG) and approximately 6 seconds elapse.

DTC CHECK/CLEAR

1. DTC CHECK 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: Body Electrical/Occupant Detection/Trouble Codes. Check the DTCs by following the prompts on the Techstream screen. HINT: Refer to the Techstream operator's manual for further details.
2. DTC CLEAR 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: Body Electrical/Occupant Detection/Trouble Codes. Clear the DTCs by following the prompts on the Techstream screen. HINT: Refer to the Techstream operator's manual for further details.

FAIL-SAFE CHART

1. FAIL SAFE FUNCTION The following chart shows the status of the controls when the system is normal and malfunctioning. 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 turned on (IG), the passenger airbag ON/OFF indicator will indicate ON or OFF depending on the conditions listed below. Condition ON Indicator OFF Indicator Front Passenger Airbag Front Seat Side Airbag RH Front Seat Belt Pretensioner RH Curtain Shield Airbag RH Adult is seated ON OFF o o o o Child is seated OFF ON X o o o Vacant OFF OFF X o X o Failure OFF ON X o o o HINT: o: Deployable X: Not deployable

DATA LIST/ACTIVE TEST

1. 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. 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: Body Electrical/Occupant Detection/Data List. Check the values by referring to the table below. Tester Display Measurement Item/Range Normal Condition Diagnostic Note IG Switch Power switch condition/ ON: Power switch on (IG) OFF: Power switch off ON/OFF - Passenger Buckle SW Passenger side buckle switch/ Set: The seat belt is fastened Unset: The seat belt is not fastened NG: Data is not determined Set/Unset - Passenger Classification Passenger classification/ AM50: Adult (more than 54 kg (119.1 lb)) is seated AF05: Adult (36 to 54 kg (79.4 to 119.1 lb)) is seated Child: Child (less than 36 kg (79.3 lb)) is seated CRS: Child restraint system is installed (less than 32 kg (70.6 lb) and passenger side buckle switch is on) OFF: Vacant AM50/AF05/Child/CRS/OFF - Sensor Range Info Sensor range information/ OK: The value of a sensor is within the range NG: The value of a sensor is over the range OK - FL Sensor Range Info Front left sensor range information/ OK: Sensor range is -17 to 27 kg (-37.5 to 59.5 lb) Min.: Less than -17 kg (-37.5 lb) Max.: More than 27 kg (59.5 lb) OK - FR Sensor Range Info Front right sensor range information/ OK: Sensor range is -17 to 27 kg (-37.5 to 59.5 lb) Min.: Less than -17 kg (-37.5 lb) Max.: More than 27 kg (59.5 lb) OK - RL Sensor Range Info Rear left sensor range information/ OK: Sensor range is -17 to 37 kg (-37.5 to 81.6 lb) Min.: Less than -17 kg (-37.5 lb) Max.: More than 37 kg (81.6 lb) OK - RR Sensor Range Info Rear right sensor range information/ OK: Sensor range is -17 to 37 kg (-37.5 to 81.6 lb) Min.: Less than -17 kg (-37.5 lb) Max.: More than 37 kg (81.6 lb) OK - FL Sensor Voltage Front left sensor voltage/ Min.: 0 V Max.: 19.8 V 0 to 5 V - FR Sensor Voltage Front right sensor voltage/ Min.: 0 V Max.: 19.8 V 0 to 5 V - RL Sensor Voltage Rear left sensor voltage/ Min.: 0 V Max.: 19.8 V 0 to 5 V - RR Sensor Voltage Rear right sensor voltage/ Min.: 0 V Max.: 19.8 V 0 to 5 V - FL Sensor Weight Info Front left sensor weight information/ Min.: -17 kg (-37.5 lb) Max.: 27 kg (59.5 lb) -17 to 27 kg (-37.5 to 59.5 lb) - FR Sensor Weight Info Front right sensor weight information/ Min.: -17 kg (-37.5 lb) Max.: 27 kg (59.5 lb) -17 to 27 kg (-37.5 to 59.5 lb) - RL Sensor Weight Info Rear left sensor weight information/ Min.: -17 kg (-37.5 lb) Max.: 37 kg (81.6 lb) -17 to 37 kg (-37.5 to 81.6 lb) - RR Sensor Weight Info Rear right sensor weight information/ Min.: -17 kg (-37.5 lb) Max.: 37 kg (81.6 lb) -17 to 37 kg (-37.5 to 81.6 lb) - Total Weight Information Total weight information/ Min.: -68 kg (-149.9 lb) Max.: 128 kg (282.2 lb) -68 to 128 kg (-149.9 to 282.2 lb) - Number of Present DTC Number of present DTC recorded/ Min.: 0, Max.: 255 0 - Number of Past DTC Number of past DTC recorded/ Min.: 0, Max.: 255 0

DIAGNOSTIC TROUBLE CODE CHART

If a trouble code is displayed during the DTC check, check the circuit listed for the code in the table below (proceed to the reference listed for that circuit).

HINT

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.

OCCUPANT CLASSIFICATION SYSTEM

See also:
• INITIALIZATION
• Trouble in Passenger Airbag ON/OFF Indicator
• GENERAL INFORMATION
• PROBLEM SYMPTOMS TABLE
• DIAGNOSTIC TROUBLE CODE CHART