B1794

SUPPLEMENTAL RESTRAINT SYSTEM: OCCUPANT CLASSIFICATION SYSTEM (for Separate Seat Type): B1794: Open in Occupant Classification ECU Battery Positive Line
B1794 - Open in Occupant Classification ECU Battery Positive Line

DESCRIPTION

DTC B1794 is set when a malfunction is detected in the occupant classification ECU.





HINT
* When DTC B1650/32 is detected as a result of troubleshooting the supplemental restraint system, perform troubleshooting for DTC B1794 of the occupant classification system.
* Use the Techstream to check for DTCs of the occupant classification ECU, otherwise the DTCs cannot be read.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK DTC

(a) Turn the ignition switch to the ON position.

(b) Clear any DTCs stored in the memory Occupant Classification System (for Separate Seat Type).

HINT
* First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.
* Use the Techstream to clear the DTCs of the occupant classification ECU, otherwise the DTCs cannot be cleared.

(c) Turn the ignition switch to the LOCK position, and wait for at least 10 seconds.

(d) Turn the ignition switch to the ON position.

(e) Using the Techstream, check for DTCs of the occupant classification ECU Occupant Classification System (for Separate Seat Type).

OK:

DTC B1794 is not output.

HINT
DTCs other than B1794 may be output at this time, but they are not related to this check.

OK -- USE SIMULATION METHOD TO CHECK
NG -- Continue to next step.

2. CHECK CONNECTION OF CONNECTORS

(a) Turn the ignition switch to the LOCK position.

(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

(c) Check that the connectors are properly connected to the center airbag sensor assembly and the occupant classification ECU.

OK:

The connectors are properly connected.

NG -- CONNECT CONNECTORS
OK -- Continue to next step.

3. CHECK CONNECTORS

(a) Check that the connectors (on the occupant classification ECU side) are not damaged Electronic Circuit Inspection Procedure.

OK:

The connectors are not deformed or damaged.

NG -- REPAIR OR REPLACE WIRE HARNESS
OK -- Continue to next step.

4. CHECK WIRE HARNESS (SOURCE VOLTAGE)

(a) Turn the ignition switch to the LOCK position.





(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

(c) Disconnect the O5 connector from the occupant classification ECU.

(d) Connect the negative (-) terminal cable to the battery.

(e) Turn the ignition switch to the ON position.

(f) Measure the voltage and resistance.

Standard resistance:





Standard voltage:





NG -- REPAIR OR REPLACE WIRE HARNESS OR BATTERY
OK -- Continue to next step.

5. CHECK DTC

(a) Turn the ignition switch to the LOCK position.

(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

(c) Connect the connectors to the occupant classification ECU.

(d) Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.

(e) Turn the ignition switch to the ON position.

(f) Clear any DTCs stored in the memory Occupant Classification System (for Separate Seat Type).

HINT
* First clear DTCs stored in the occupant classification ECU and then in the center airbag sensor assembly.
* Use the Techstream to clear the DTCs of the occupant classification ECU, otherwise the DTCs cannot be cleared.

(g) Turn the ignition switch to the LOCK position, and wait for at least 10 seconds.

(h) Turn the ignition switch to the ON position.

(i) Using the Techstream, check for DTCs of the occupant classification ECU Occupant Classification System (for Separate Seat Type).

OK:

DTC B1794 is not output.

HINT
DTCs other than B1794 may be output at this time, but they are not related to this check.

OK -- USE SIMULATION METHOD TO CHECK
NG -- Continue to next step.

6. REPLACE OCCUPANT CLASSIFICATION ECU

(a) Turn the ignition switch to the LOCK position.

(b) Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.

(c) Replace the occupant classification ECU Removal.

HINT
Perform the inspection using parts from a normal vehicle when possible.

NEXT -- Continue to next step.

7. PERFORM ZERO POINT CALIBRATION

(a) Connect the negative (-) terminal cable to the battery.

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to the ON position.

(d) Using the Techstream, perform the zero point calibration Occupant Classification System (for Separate Seat Type).

OK:

"Zero Point Calibration is complete." is displayed on the Techstream.

NEXT -- Continue to next step.

8. PERFORM SENSITIVITY CHECK

(a) Using the Techstream, perform the sensitivity check Occupant Classification System (for Separate Seat Type).

Standard:

27 to 33 kg (59.52 to 72.75 lb)

NEXT -- END