NO.2 AIR BAG SYSTEM WARNING LIGHT IS ILLUMINATED CONSTANTLY [AIR BAG SYSTEM]

id0803a3812400

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


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.
(See BATTERY INSPECTION [L8, LF].)
2
VERIFY THAT SAS CONTROL MODULE 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.
•  Turn the ignition switch to the LOCK position.
•  Remove the battery cover.
•  Disconnect the negative battery cable and wait for 1 min or more.
•  Are all SAS control module 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 CONTROL MODULE 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 seat connectors.
•  Remove the back trim.
•  Disconnect the driver and passenger-side pre-tensioner seat belt connectors.
•  Disconnect all SAS control module connectors.
•  Disconnect the instrument cluster connector.
•  Is there continuity between SAS control module connector terminal 1R 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 CONTROL MODULE AND INSTRUMENT CLUSTER FOR SHORT TO POWER SUPPLY
•  Connect the negative battery cable.
•  Turn the ignition switch to the 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.
(See INSTRUMENT CLUSTER REMOVAL/INSTALLATION.)
No
Go to the next step.
6
INSPECT POWER SUPPLY CIRCUIT OF SAS CONTROL MODULE (TERMINAL 1W)
•  Turn the ignition switch to the LOCK position.
•  Remove the battery cover.
•  Disconnect the negative battery cable and wait for 1 min or more.
•  Connect all SAS control module connectors.
•  Connect the driver and passenger-side
pre-tensioner seat belt connectors.
•  Connect the driver and passenger-side seat connectors.
•  Connect the passenger-side air bag module connector.
•  Connect the driver-side air bag module connector.
•  Inspect the voltage for PID/DATA monitor IGN_V_2 item using M-MDS.
•  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 the 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 CONTROL MODULE CONNECTOR TERMINAL 1I IS GROUND
•  Turn the ignition switch to the LOCK position.
•  Remove the battery cover.
•  Disconnect the negative battery cable and wait for 1 min or more.
•  Disconnect the clock spring connector.
•  Disconnect the passenger-side air bag module connector.
•  Disconnect the driver and passenger-side seat connectors.
•  Disconnect the driver and passenger-side pre-tensioner seat belt connectors.
•  Disconnect all SAS control module control model connectors.
•  Inspect the wiring harness between SAS control module connector terminal 1I and ground for the following:
―  Short to power supply
―  Open circuit
•  Is the wiring harness normal?
Yes
Replace the SAS control module, then go to the next step.
(See SAS CONTROL MODULE REMOVAL/INSTALLATION.)
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 the LOCK position.
•  Remove the battery cover.
•  Disconnect the negative battery cable and wait for 1 min or more.
•  Connect all SAS control module connectors.
•  Connect the driver and passenger-side
pre-tensioner seat belt connectors.
•  Connect the driver and passenger-side seat 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 the 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.