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Occupant Classification System (Diagnostic Codes & Symptom Tests): Diagnosis Lexus GS IV

Airbag 2 illustrations ~3008 words

INSPECTION PROCEDURE

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

HINT

  1. If troubleshooting (wire harness inspection) is difficult to perform, remove the front seat RH installation bolts to see the undersurface of the seat cushion.
  2. In the above case, hold the seat so that it does not fall down. Holding the seat for a long period of time may cause a problem, such as seat rail deformation. Hold the seat up only for as long as necessary.

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

HINT

  1. If troubleshooting (wire harness inspection) is difficult to perform, remove the front seat RH installation bolts to see the undersurface of the seat cushion.
  2. In the above case, hold the seat so that it does not fall down. Holding the seat for a long period of time may cause problems, such as seat rail deformation. Hold the seat up only for as long as necessary.

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

HINT

  1. If troubleshooting (wire harness inspection) is difficult to perform, remove the front seat RH installation bolts to see the undersurface of the seat cushion.
  2. In the above case, hold the seat so that it does not fall down. Holding the seat for a long period of time may cause problems, such as seat rail deformation. Hold the seat up only for as long as necessary.

Scheme 275

Scheme 275: PROCEDURE
Scheme 275: PROCEDURE
  1. CHECK FOR DTC Turn the power switch on (IG), and wait for at least 60 seconds. Clear the DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . HINT: First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor. Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared. Turn the power switch off. Turn the power switch on (IG), and wait for at least 60 seconds. Check for DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . OK DTC B1783 is not output. HINT: DTCs other than DTC B1783 may be output at this time, but they are not related to this check. NG --> See step 2 OK --> See step 13
  2. CHECK CONNECTION OF CONNECTOR Turn the power switch off. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds. Check that the connectors are properly connected to the occupant detection ECU and rear occupant classification sensor RH. OK Connectors are properly connected. NG --> CONNECT CONNECTOR OK: Go to next step
  3. CHECK CONNECTOR Disconnect the connectors from the occupant detection ECU and rear occupant classification sensor RH. Check that the connectors (on the occupant detection ECU side and rear occupant classification sensor RH side) are not damaged. Refer to «DIAGNOSIS SYSTEM [03/2012 - ]»(ref-600447-S30509936882014022400000) . OK Connectors are not deformed or damaged. *1 Rear Occupant Classification Sensor RH *2 Occupant Detection ECU *3 Front Seat Inner Belt Assembly RH NG --> See step 14 OK: Go to next step
  4. CHECK FRONT SEAT INNER BELT ASSEMBLY RH Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds. Turn the power switch on (IG). Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Switch Condition Specified Condition z13-2 - Body ground Power switch on (IG) Below 1 V z13-4 - Body ground z13-6 - Body ground Turn the power switch off. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds. Using service wires, connect terminals 1 and 3, and terminals 2 and 3 of connector C. NOTE: Do not forcibly insert the service wires into the terminals of the connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition z13-2 - z13-6 Always Below 1 ohms z13-4 - z13-6 Disconnect the service wires from connector C. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition z13-2 - z13-6 Always 1 Mohms or higher z13-4 - z13-6 z13-2 - z13-4 z13-2 - Body ground z13-4 - Body ground z13-6 - Body ground TEXT IN ILLUSTRATION *1 Front Seat Inner Belt Assembly RH *2 Rear Occupant Classification Sensor RH *3 Occupant Detection ECU *4 Service Wire *5 Connector C *6 Connector B *a Front view of wire harness connector (to Rear Occupant Classification Sensor RH) *b Front view of wire harness connector (to Occupant Detection ECU) NG --> See step 14 OK: Go to next step
  5. CHECK FOR DTC Connect the connectors to the occupant detection ECU and rear occupant classification sensor RH. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds. Turn the power switch on (IG), and wait for at least 60 seconds. Clear the DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . HINT: First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor. Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared. Turn the power switch off. Turn the power switch on (IG), and wait for at least 60 seconds. Check for DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . OK DTC B1783 is not output. HINT: DTCs other than DTC B1783 may be output at this time, but they are not related to this check. NG --> See step 6 OK --> See step 13
  6. CHECK OCCUPANT DETECTION ECU Turn the power switch off. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds. Replace the occupant detection ECU. Refer to «REMOVAL [03/2012 - ]»(ref-600605-S03598035512014022400000) . HINT: Perform the inspection using parts from a normal vehicle when possible. NEXT: Go to next step
  7. PERFORM ZERO POINT CALIBRATION Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds. Turn the power switch on (IG). Perform the zero point calibration. Refer to «INITIALIZATION [03/2012 - ]»(ref-600447-S01415728602014022400000) . OK "Zero Point Calibration is complete." is displayed. NG --> See step 10 OK: Go to next step
  8. PERFORM SENSITIVITY CHECK Perform the sensitivity check. Refer to «INITIALIZATION [03/2012 - ]»(ref-600447-S01415728602014022400000) . Standard 27 to 33 kg (59.5 to 72.8 lb) NG --> See step 10 OK: Go to next step
  9. CHECK FOR DTC Clear the DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . HINT: First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor. Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared. Turn the power switch off. Turn the power switch on (IG), and wait for at least 60 seconds. Check for DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . OK DTC B1783 is not output. HINT: DTCs other than DTC B1783 may be output at this time, but they are not related to this check. NG --> See step 10 OK --> END (OCCUPANT DETECTION ECU WAS DEFECTIVE)
  10. CHECK FRONT SEAT ADJUSTER ASSEMBLY RH (REAR OCCUPANT CLASSIFICATION SENSOR RH) Turn the power switch off. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds. Replace the front seat adjuster assembly RH. for Standard Seat Type. Refer to «REMOVAL [03/2012 - ]»(ref-600608-S36428769182014022400000) for Luxury Seat Type. Refer to «REMOVAL [03/2012 - ]»(ref-600608-S14483777922014022400000) HINT: Perform the inspection using parts from a normal vehicle when possible. NEXT: Go to next step
  11. PERFORM ZERO POINT CALIBRATION Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds. Turn the power switch on (IG). Perform the zero point calibration. Refer to «INITIALIZATION [03/2012 - ]»(ref-600447-S01415728602014022400000) . OK "Zero Point Calibration is complete." is displayed. NEXT: Go to next step
  12. PERFORM SENSITIVITY CHECK Perform the sensitivity check. Refer to «INITIALIZATION [03/2012 - ]»(ref-600447-S01415728602014022400000) . Standard 27 to 33 kg (59.5 to 72.8 lb) NEXT --> END (FRONT SEAT ADJUSTER ASSEMBLY RH [REAR OCCUPANT CLASSIFICATION SENSOR RH] WAS DEFECTIVE)
  13. USE SIMULATION METHOD TO CHECK. Refer to «DIAGNOSIS SYSTEM [03/2012 - ]»(ref-600447-S30509936882014022400000)
  14. REPLACE FRONT SEAT INNER BELT ASSEMBLY RH. Refer to «REMOVAL [03/2012 - ]»(ref-600659-S00218149932014022400000)

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

HINT

  1. If troubleshooting (wire harness inspection) is difficult to perform, remove the front RH seat installation bolts to see the undersurface of the seat cushion.
  2. In the above case, hold the seat so that it does not fall down. Holding the seat for a long period of time may cause problems, such as seat rail deformation. Hold the seat up only for as long as necessary.

Scheme 276

Scheme 276: PROCEDURE
Scheme 276: PROCEDURE
  1. CHECK FOR DTC Turn the power switch on (IG), and wait for at least 60 seconds. Clear the DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . HINT: First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor. Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared. Turn the power switch off. Turn the power switch on (IG), and wait for at least 60 seconds. Check for DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . OK DTC B1790 is not output. HINT: DTCs other than DTC B1790 may be output at this time, but they are not related to this check. NG --> See step 2 OK --> See step 11
  2. CHECK CONNECTION OF CONNECTOR Turn the power switch off. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds. Check that the connectors are properly connected to the occupant detection ECU and center airbag sensor. OK Connectors are properly connected. NG --> CONNECT CONNECTOR OK: Go to next step
  3. CHECK CONNECTOR Disconnect the connectors from the center airbag sensor and occupant detection ECU. Check that the connectors (on the center airbag sensor side and occupant detection ECU side) are not damaged. Refer to «DIAGNOSIS SYSTEM [03/2012 - ]»(ref-600447-S30509936882014022400000) . OK Connectors are not deformed or damaged. TEXT IN ILLUSTRATION *1 Occupant Detection ECU *2 Center Airbag Sensor Assembly NG --> REPLACE HARNESS AND CONNECTOR OK: Go to next step
  4. CHECK CENTER AIRBAG SENSOR CIRCUIT Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds. Turn the power switch on (IG). Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Switch Condition Specified Condition z12-7 (FSR+) - Body ground Power switch on (IG) Below 1 V z12-4 (FSR-) - Body ground Turn the power switch off. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds. Using a service wire, connect terminals 9 (FSR+) and 17 (FSR-) of connector B. NOTE: Do not forcibly insert the service wire into the terminals of the connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition z12-7 (FSR+) - z12-4 (FSR-) Always Below 1 ohms Disconnect the service wire from connector B. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition z12-7 (FSR+) - z12-4 (FSR-) Always 1 Mohms or higher z12-7 (FSR+) - Body ground z12-4 (FSR-) - Body ground TEXT IN ILLUSTRATION *1 Occupant Detection ECU *2 Center Airbag Sensor Assembly *3 Connector E *4 Connector B *5 Service Wire *a Front view of wire harness connector (to Occupant Detection ECU) *b Rear view of wire harness connector (to Center Airbag Sensor Assembly) NG --> See step 10 OK: Go to next step
  5. CHECK FOR DTC Connect the connectors to the occupant detection ECU and center airbag sensor. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds. Turn the power switch on (IG), and wait for at least 60 seconds. Clear the DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . HINT: First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor. Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared. Turn the power switch off. Turn the power switch on (IG), and wait for at least 60 seconds. Check for DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . OK DTC B1790 is not output. HINT: DTCs other than DTC B1790 may be output at this time, but they are not related to this check. NG --> See step 6 OK --> See step 13
  6. CHECK OCCUPANT DETECTION ECU Turn the power switch off. Disconnect the cable from the negative (-) auxiliary battery terminal, and wait for at least 90 seconds. Replace the occupant detection ECU. Refer to «REMOVAL [03/2012 - ]»(ref-600605-S03598035512014022400000) . HINT: Perform the inspection using parts from a normal vehicle when possible. NEXT: Go to next step
  7. PERFORM ZERO POINT CALIBRATION Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds. Turn the power switch on (IG). Perform the zero point calibration. Refer to «INITIALIZATION [03/2012 - ]»(ref-600447-S01415728602014022400000) . OK "Zero Point Calibration is complete." is displayed. NEXT: Go to next step
  8. PERFORM SENSITIVITY CHECK Perform the sensitivity check. Refer to «INITIALIZATION [03/2012 - ]»(ref-600447-S01415728602014022400000) . Standard 27 to 33 kg (59.5 to 72.8 lb) NEXT: Go to next step
  9. CHECK FOR DTC Clear the DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . HINT: First clear the DTCs stored in the occupant detection ECU, and then clear the DTCs stored in the center airbag sensor. Use the Techstream to clear the DTCs of the occupant detection ECU, otherwise the DTCs cannot be cleared. Turn the power switch off. Turn the power switch on (IG), and wait for at least 60 seconds. Check for DTCs. Refer to «DTC CHECK / CLEAR [03/2012 - ]»(ref-600447-S14231737302014022400000) . OK DTC B1790 is not output. HINT: DTCs other than DTC B1790 may be output at this time, but they are not related to this check. NG --> See step 12 OK --> END (OCCUPANT DETECTION ECU WAS DEFECTIVE)
  10. CHECK FRONT SEAT INNER BELT ASSEMBLY RH Disconnect the front seat inner belt assembly RH connector from the floor wire. Connect the cable to the negative (-) auxiliary battery terminal, and wait for at least 2 seconds. Turn the power switch on (IG). Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Switch Condition Specified Condition T4-1 (FSR+) - Body ground Power switch on (IG) Below 1 V T4-4 (FSR-) - Body ground Turn the power switch off. Disconnect the connector from the occupant detection ECU. Using a service wire, connect terminals 7 (FSR+) and 4 (FSR-) of connector E. NOTE: Do not forcibly insert the service wire into the terminals of the connector. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition T4-1 (FSR+) - T4-4 (FSR-) Always Below 1 ohms Disconnect the service wire from connector E. Measure the resistance according to the value(s) in the table below. Standard Resistance Tester Connection Condition Specified Condition T4-1 (FSR+) - T4-4 (FSR-) Always 1 Mohms or higher T4-1 (FSR+) - Body ground T4-4 (FSR-) - Body ground TEXT IN ILLUSTRATION *1 Front Seat Inner Belt Assembly RH *2 Floor Wire *3 Occupant Detection ECU *4 Center Airbag Sensor Assembly *5 Service Wire *6 Connector E *7 Connector D *a Front view of wire harness connector (to Occupant Detection ECU) *b Front view of wire harness connector (to Floor Wire) NG --> See step 14 OK --> REPLACE FLOOR WIRE
  11. USE SIMULATION METHOD TO CHECK. Refer to «DIAGNOSIS SYSTEM [03/2012 - ]»(ref-600447-S30509936882014022400000)
  12. REPLACE CENTER AIRBAG SENSOR ASSEMBLY. Refer to «REMOVAL [03/2012 - ]»(ref-600605-S37458183002014022400000)
  13. USE SIMULATION METHOD TO CHECK. Refer to «DIAGNOSIS SYSTEM [03/2012 - ]»(ref-600447-S30509936882014022400000)
  14. REPLACE FRONT SEAT INNER BELT ASSEMBLY RH. Refer to «REMOVAL [03/2012 - ]»(ref-600659-S00218149932014022400000)

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

HINT

  1. If troubleshooting (wire harness inspection) is difficult to perform, remove the front seat RH installation bolts to see the undersurface of the seat cushion.
  2. In the above case, hold the seat so that it does not fall down. Holding the seat for a long period of time may cause problems, such as seat rail deformation. Hold the seat up only for as long as necessary.

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] . Inspect the fuses for circuits related to this system before performing the following inspection procedure.

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

Note. When disconnecting the cable, some systems need to be initialized after the cable is reconnected. Refer to INITIALIZATION [03/2012 - ] .

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