DTC Always Normal

SOURCE VOLTAGE DROP

CIRCUIT DESCRIPTION




The SRS is equipped with a voltage-increase circuit (DC-DC converter) in the air bag sensor assembly center in case the source voltage drops.

When the battery voltage drops, the voltage-increase circuit (DC-DC converter) functions to increase the voltage of the SRS to normal voltage.

A malfunction in this circuit is displayed differently from other codes. The source voltage drop is indicated when the SRS warning light comes on without showing any DTCs.

A malfunction in this circuit is not recorded in the air bag sensor assembly center. The SRS warning light automatically goes off when the source voltage returns to normal.

Wiring Diagram:

Step 1 - 2:

Step 3 - 4:

INSPECTION PROCEDURE

CAUTION: Be sure to perform the following procedures before troubleshooting to avoid unexpected air bag deployment.

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 air bag sensor assembly center.
d. Disconnect the connectors from the horn button assembly.
e. Disconnect the connectors from the front passenger air bag assembly.
f. w/ Side air bag: Disconnect the connector from the front seat air bag assembly LH.
g. w/ Side air bag: Disconnect the connector from the front seat air bag assembly RH.
h. w/ Curtain shield air bag: Disconnect the connector from the curtain shield air bag assembly LH.
i. w/ Curtain shield air bag: Disconnect the connector from the curtain shield air bag assembly RH.
j. Disconnect the connector from the front seat outer belt assembly LH.
k. Disconnect the connector from the front seat outer belt assembly RH.