B1791

DTC B1791 Collision Detection Signal Line Malfunction

DESCRIPTION

DTC Detections Conditions:

The center airbag sensor assembly communication circuit consists of the occupant classification ECU and the center airbag sensor assembly.

DTC B1791 is set when a malfunction is detected in the center airbag sensor assembly communication circuit.

HINT:
- When DTC B1650/32 is detected as a result of troubleshooting for the supplemental restraint system, check the DTCs stored in the occupant classification ECU, and perform troubleshooting for those DTCs first.
- Use the intelligent tester to check for DTCs of the occupant classification ECU, otherwise the DTC cannot be read.

Wiring Diagram:

INSPECTION PROCEDURE

CAUTION: In order to prevent unexpected airbag deployment, disconnect the following connectors before inspecting parts such as wire harnesses, if the application of tester probes to the center airbag sensor assembly connector is necessary.

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 connectors from the center airbag sensor assembly.
d. Disconnect the connectors from the steering pad assembly.
e. Disconnect the connector from the front passenger airbag assembly.
f. Disconnect the connector from the front seat outer belt assembly LH.
g. Disconnect the connector from the front seat outer belt assembly RH.

HINT: Skip the following steps if side and curtain shield airbags are not fitted.

h. Disconnect the connector from the front seat side airbag assembly LH.
i. Disconnect the connector from the front seat side airbag assembly RH.
j. Disconnect the connector from the curtain shield airbag assembly LH.
k. Disconnect the connector from the curtain shield airbag assembly RH.

HINT:
- If troubleshooting (wire harness inspection) is difficult to perform, remove the front RH seat assembly installation bolts to see the under surface of the seat cushion.
- In the case, hold the seat so that it does not tip over. Holding the seat up for a long period of time may cause problems, such as seat rail deformation. Hold the seat up only for as long as necessary.

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