NO.2 AIR BAG SYSTEM WARNING LIGHT IS ILLUMINATED CONSTANTLY


BHE080301046W03

2

Air bag system warning light is illuminated constantly.

DETECTION CONDITION

Malfunction in air bag system warning light circuit (open circuit or short to power supply).

POSSIBLE CAUSE

• Weak battery
• SAS unit malfunction
• Instrument cluster (circuit board) malfunction
• No connection in SAS unit connector
• Poor contact in instrument cluster connector (24-pin)
• Open or short to power supply circuit in wiring harness between instrument cluster and SAS unit
• Poor contact at terminals 1T, 1X and/or 1W of SAS unit connector
• Poor contact in wiring harness between terminal 1X of SAS unit connector and ground
• Poor contact in wiring harness between battery and terminal 1W of SAS unit

Diagnostic Procedure

• When performing an asterisked (*) troubleshooting inspection, slightly shake the wiring harness and connectors while performing the inspection to discover whether poor contact points are the cause of any intermittent malfunction. If there is a problem, verify that connectors, terminals and wiring harness are connected correctly and undamaged.

STEP

INSPECTION

ACTION

1

INSPECT BATTERY

• Measure the voltage of battery.
• Is the voltage 9 V or more?
Yes
Go to the next step.
No
Battery is weak.
Inspect charge/discharge system, then go to Step 9.
2

VERIFY THAT SAS UNIT CONNECTOR IS CONNECTED

Warning
• Handling the air bag system components improperly can accidentally deploy the air bag modules and pre-tensioner seat belts, which may seriously injure you. Read the service warnings and cautions before handling the air bag system components.
(See SERVICE WARNINGS.)
(SeeSERVICE CAUTIONS.)
• Turn the ignition switch to LOCK position.
• Disconnect the negative battery cable and wait for 1 min or more.
• Turn up the floor covering.
• Are all SAS unit connectors securely connected?
Yes
Go to the next step.
No
Reconnect the connector properly, then go to Step 9.
* 3

INSPECT WIRING HARNESS BETWEEN SAS UNIT AND INSTRUMENT CLUSTER FOR CONTINUITY

• Remove the column cover.
• Disconnect the clock spring connector.
• Remove the glove compartment.
• Disconnect the passenger-side air bag module connector.
• Disconnect the driver and passenger-side side air bag module connectors.
• Disconnect the driver and passenger-side curtain air bag module connectors.
• Remove the rear door lower trims.
• Disconnect the driver- and passenger-side pre-tensioner seat belt connectors.
• Partially peel back the floor covering.
• Disconnect all SAS unit connectors.
• Disconnect the instrument cluster connector.
• Is there continuity between SAS unit connector terminal 1T and instrument cluster connector terminal 2K?
Yes
Go to the next step.
No
Replace the wiring harness, then go to Step 9.
* 4

INSPECT WIRING HARNESS BETWEEN SAS UNIT AND INSTRUMENT CLUSTER FOR SHORT TO POWER SUPPLY

• Connect the negative battery cable.
• Turn the ignition switch to ON position.
• Measure the voltage at instrument cluster connector terminal 2K.
• Is the voltage 9 V or more?
Yes
Replace the wiring harness, then go to Step 9.
No
Go to the next step.
5

CHECK TO SEE WHETHER MALFUNCTION IS IN AIR BAG SYSTEM WARNING LIGHT IN INSTRUMENT CLUSTER

• Connect instrument cluster connector terminal 2K to ground, then reconnect the connector
• Does the air bag system warning light illuminate with ignition switch ON?
Yes
Replace the instrument cluster, then go to Step 9.
No
Go to the next step.
6

INSPECT POWER SUPPLY CIRCUIT OF SAS UNIT (TERMINAL 1W)

• Turn the ignition switch to LOCK position.
• Disconnect the negative battery cable and wait for 1 min or more.
• Connect all SAS unit connectors.
• Connect the driver and passenger-side pre-tensioner seat belt connectors.
• Connect the driver and passenger-side curtain air bag module connectors.
• Connect the driver and passenger-side side air bag module connectors.
• Connect the passenger-side air bag module connector.
• Connect the clock spring connector.
• Inspect the voltage for PID/DATA monitor RCM_VOLT item using WDS or equivalent.
• Is the voltage of at least one terminal 9 V or more?
Yes
Go to the Step 8.
No
Go to the next step.
7

INSPECT WIRING HARNESS BETWEEN BATTERY AND FUSE BLOCK

• Connect the negative battery cable.
• Turn the ignition switch to ON position.
• Measure the voltage at instrument cluster connector terminal 1G.
• Is the voltage 9 V or more?
Yes
Go to the next step.
No
Repair the wiring harnesses, then go to Step 9.
8

VERIFY THAT SAS UNIT CONNECTOR TERMINAL 1X IS GROUND

• Turn the ignition switch to LOCK position.
• Disconnect the negative battery cable and wait for 1 min or more.
• Remove the column cover.
• Disconnect the clock spring connector.
• Remove the glove compartment.
• Disconnect the passenger-side air bag module connector.
• Disconnect the driver and passenger-side side air bag module connectors.
• Disconnect the driver and passenger-side curtain air bag module connectors.
• Remove the rear door lower trims.
• Disconnect the driver and passenger-side pre-tensioner seat belt connectors.
• Partially peel back the floor covering.
• Disconnect all SAS unit control model connectors.
• Inspect the wiring harness between SAS unit connector terminal 1X and ground for the following:
– Short to power supply
– Open circuit
• Is the wiring harness okay?
Yes
Replace the SAS unit, then go to the next step.
No
Replace the wiring harnesses, then go to the next step.
9

CONFIRM THAT MALFUNCTION SYMPTOMS DO NOT RECUR AFTER REPAIR

• Turn the ignition switch to LOCK position.
• Disconnect the negative battery cable and wait for 1 min or more.
• Connect all SAS unit connectors.
• Connect the driver and passenger-side pre-tensioner seat belt connectors.
• Connect the driver and passenger-side curtain air bag module connectors.
• Connect the driver and passenger-side side air bag module connectors.
• Connect the passenger-side air bag module connector.
• Connect the clock spring connector.
• Connect the instrument cluster connector.
• Connect the negative battery cable.
• Turn the ignition switch to ON position.
• Does the air bag system warning light operate properly?
Yes
Complete troubleshooting, then explain repairs to customer.
No
Recheck malfunction symptoms, then repeat from Step 1 if malfunction recurs.