Source Voltage Drop

SOURCE VOLTAGE DROP

CIRCUIT DESCRIPTION

Detection Item:

The SRS is equipped with a voltage-increase circuit (DC-DC converter) in the airbag sensor center when the source voltage drops. When the battery voltage drops, the voltage-increase circuit (DC-DC converter) increases the voltage of the SRS to normal voltage.
The diagnosis system malfunction display for this circuit is different from other circuits. When the SRS warning lamp remains on and the DTC is a normal code, a source voltage drop is indicated.
Malfunctions in this circuit are not recorded in the airbag sensor center. When the source voltage returns to normal, the SRS warning lamp automatically turns off.

Wiring Diagram:

Step 1-2:

Step 3:

INSPECTION PROCEDURE

CAUTION: Be sure to perform the following procedures before troubleshooting to avoid unexpected airbag and seat belt pretensioner activation.

a. Turn the ignition switch OFF.
b. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.
c. Disconnect the connectors from the airbag sensor center.
d. Disconnect the connector from the horn button.
e Disconnect the connector from the front passenger airbag.
f. Disconnect the connector from the front seat airbag LH.
g. Disconnect the connector from the front seat airbag RH.
h. Disconnect the connector from the front seat outer belt LH.
i. Disconnect the connector from the front seat outer belt RH.