Inspection Procedure

1. Turn the ignition switch to the ON position, and wait for at least 10 seconds.
2. Check the DTCs (See DTC CHECK / CLEAR  ).

   Result: 

   A: DTCs B1771 and B1795 are output. 

   B: DTC B1795 is output. 

   HINT:

   Codes other than DTC B1771 and B1795 may be output at this time, but they are not related to this check.

A: GO TO DTC B1771 

B: Go to Next Step 

1. Measure the resistance of the ECU-B fuse.

   Standard resistance: 

   Below 1 Ω 

NG: REPLACE FUSE 

OK : Go to Next Step 

1. Turn the ignition switch to the LOCK position.
2. Disconnect the negative (-) terminal cable from the battery.
3. Disconnect the connector from the occupant classification ECU.
4. Connect the negative (-) terminal cable to the battery.
5. Turn the ignition switch to the ON position.
6. Measure the voltage according to the value(s) in the table below.
   Fig 1: Identifying Ignition Switch Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard voltage 

   WIRE HARNESS (SOURCE VOLTAGE) VOLTAGE
   
   

   Tester connection	Condition	Specified condition
   O4-1 (+B) - Body ground	Always	10 to 14 V
   O4-7 (IG) - Body ground	Ignition switch ON	10 to 14 V

7. Turn the ignition switch to the LOCK position.
8. Measure the resistance according to the value(s) in the table below.

   Standard resistance 

   WIRE HARNESS (SOURCE VOLTAGE) RESISTANCE
   
   

   Tester connection	Condition	Specified condition
   O4-3 (GND) - Body ground	Always	Below 1 Ω

NG: REPAIR OR REPLACE WIRE HARNESS 

OK : Go to Next Step 

1. Turn the ignition switch to the LOCK position.
2. Disconnect the negative (-) terminal cable from the battery.
3. Replace the occupant classification ECU (See REMOVAL  ).

   HINT:

   Perform the inspection using parts from a normal vehicle if possible.

1. Connect the negative (-) terminal cable to the battery.
2. Connect the intelligent tester to the DLC3.
3. Turn the ignition switch to the ON position.
4. Using the intelligent tester, perform "Zero point calibration" (See INITIALIZATION  ).

   OK: The "COMPLETED" is displayed. 

1. Using the intelligent tester, perform "Sensitivity check" (See INITIALIZATION  ).

   Standard values: 27 to 33 kg (59.52 to 72.75 lb) 

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