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Up to 08/2009





SUPPLEMENTAL RESTRAINT SYSTEMS: AIRBAG SYSTEM: SRS Warning Light Remains ON
- SRS Warning Light Remains ON

DESCRIPTION

The SRS warning light is located on the combination meter assembly.

When the SRS is normal, the SRS warning light comes on for approximately 6 seconds after the power switch is turned from off to on (IG), and then goes off automatically.

If there is a malfunction in the SRS, the SRS warning light comes on to inform the driver of a problem.

When terminals TC and CG of the DLC3 are connected, the DTC is displayed by blinking of the SRS warning light.

The SRS is equipped with a voltage-increase circuit (DC-DC converter) in the center airbag sensor assembly 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. In addition, when the voltage drops, the SRS waning light will illuminate.

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

The signal to illuminate the SRS warning light is transmitted from the center airbag sensor assembly to the combination meter assembly through the CAN communication system.

WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK SRS WARNING LIGHT OPERATION

(a) Check the SRS warning light operation approximately 6 seconds after the power switch is turned on (IG).

Result:





B -- CHECK CAN COMMUNICATION SYSTEM
A -- Continue to next step.

2. CHECK BATTERY VOLTAGE

(a) Measure the battery voltage with the power switch off.

Standard Voltage:

11 to 14 V

NG -- INSPECT CHARGING SYSTEM AND BATTERY
OK -- Continue to next step.

3. CHECK CONNECTOR

(a) Turn the power switch off.

(b) Disconnect the cable from the negative (-) battery terminal.

NOTICE:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(c) Check that the connector is properly connected to the center airbag sensor assembly.

OK:

The connector is properly connected.

HINT
If the connector is not connected securely, reconnect the connector and proceed to the next inspection.

(d) Disconnect the connector from the center airbag sensor assembly.

(e) Check that the terminal of the connector is not damaged.

OK:

The terminal is not deformed or damaged.

NG -- REPLACE WIRE HARNESS
OK -- Continue to next step.

4. CHECK WIRE HARNESS (CENTER AIRBAG SENSOR ASSEMBLY - BODY GROUND)

(a) Connect the cable to the negative (-) battery terminal.





(b) Turn the power switch on (IG).

(c) Operate all components of the electrical system (defogger, wipers, headlights, heater blower, etc.).

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





(e) Turn the power switch off.

(f) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPLACE WIRE HARNESS
OK -- Continue to next step.

5. CHECK SRS WARNING LIGHT

(a) Turn the power switch on (IG).

(b) Check the SRS warning light condition.

OK:

After the primary check period, the SRS warning light goes off for approximately 10 seconds and turns back on.

HINT
The primary check period is approximately 6 seconds after the power switch is turned on (IG).

NG -- REPLACE COMBINATION METER ASSEMBLY Removal

OK -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal

6. CHECK CAN COMMUNICATION SYSTEM

(a) Use the Techstream to check if the CAN communication system is functioning normally.

HINT
* Refer to Bus Check for the CAN communication system Diagnosis System.
* The center airbag sensor assembly is connected to the CAN communication system. Therefore, before starting troubleshooting, make sure to check that there is no trouble in the CAN communication system.

Result:





B -- GO TO CAN COMMUNICATION SYSTEM How to Proceed With Troubleshooting
A -- Continue to next step.

7. CHECK BATTERY VOLTAGE

(a) Measure the battery voltage with the power switch off.

Standard Voltage:

11 to 14 V

NG -- INSPECT CHARGING SYSTEM AND BATTERY
OK -- Continue to next step.

8. CHECK CONNECTOR

(a) Turn the power switch off.

(b) Disconnect the cable from the negative (-) battery terminal.

NOTICE:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(c) Check that the connector is properly connected to the center airbag sensor assembly.

OK:

The connector is properly connected.

HINT
If the connector is not connected securely, reconnect the connector and proceed to the next inspection.

(d) Disconnect the connector from the center airbag sensor assembly.

(e) Check that the terminal of the connector is not damaged.

OK:

The terminal is not deformed or damaged.

NG -- REPLACE WIRE HARNESS
OK -- Continue to next step.

9. CHECK WIRE HARNESS (CENTER AIRBAG SENSOR ASSEMBLY - BODY GROUND)

(a) Connect the cable to the negative (-) battery terminal.





(b) Turn the power switch on (IG).

(c) Operate all components of the electrical system (defogger, wipers, headlights, heater blower, etc.).

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





(e) Turn the power switch off.

(f) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPLACE WIRE HARNESS
OK -- Continue to next step.

10. CHECK CONNECTOR

(a) Disconnect the cable from the negative (-) battery terminal.

NOTICE:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(b) Check that the connector is properly connected to the combination meter assembly.

OK:

The connector is properly connected.

HINT
If the connector is not connected securely, reconnect the connector and proceed to the next inspection.

(c) Disconnect the connector from the combination meter assembly.

(d) Check that the terminal of the connector is not damaged.

OK:

The terminal is not deformed or damaged.

NG -- REPLACE WIRE HARNESS
OK -- Continue to next step.

11. CHECK WIRE HARNESS (COMBINATION METER ASSEMBLY - BODY GROUND)

(a) Connect the cable to the negative (-) battery terminal.





(b) Turn the power switch on (IG).

(c) Measure the voltage according to the value(s) in the table below.

Standard Voltage:





(d) Turn the power switch off.

(e) Measure the resistance according to the value(s) in the table below.

Standard Resistance:





Text in Illustration





NG -- REPLACE WIRE HARNESS
OK -- Continue to next step.

12. CHECK SRS WARNING LIGHT

(a) Disconnect the cable from the negative (-) battery terminal.

NOTICE:
Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(b) Connect the connector to the combination meter assembly.

(c) Connect the cable to the negative (-) battery terminal.

(d) Turn the power switch on (IG).

(e) Check the SRS warning light condition.

OK:

After the primary check period, the SRS warning light goes off for approximately 10 seconds and turns back on.

HINT
The primary check period is approximately 6 seconds after the power switch is turned on (IG).

NG -- REPLACE COMBINATION METER ASSEMBLY Removal

OK -- REPLACE CENTER AIRBAG SENSOR ASSEMBLY Removal
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