Nissan Altima (L32) 2007-2012 Service Manual: On board diagnostic (OBD) system

Trouble Diagnosis Introduction

CAUTION: • Do not use electrical test equipment on any circuit related to the SRS unless instructed to do so in this Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harness connectors.

• Keep ground connections clean.

DIAGNOSIS FUNCTION

The SRS self-diagnosis results can be read by using “AIR BAG” warning lamp and/or CONSULT-III.

The User mode is exclusively prepared for the customer (driver). This mode warns the driver of a system malfunction through the operation of the “AIR BAG” warning lamp.

The Diagnosis mode allows the technician to locate and inspect the malfunctioning part.

The mode applications for the “AIR BAG” warning lamp and CONSULT-III are as follows:

HOW TO PERFORM TROUBLE DIAGNOSES FOR QUICK AND ACCURATE REPAIR

A good understanding of the malfunction conditions can make troubleshooting faster and more accurate.

In general, each customer feels differently about a malfunction. It is important to fully understand the symptoms or conditions for a customer complaint.

Information From Customer

WHAT - Vehicle model

WHEN - Date, Frequencies

WHERE - Road conditions

HOW - Operating conditions, Symptoms

Preliminary Check

Check that the following parts are in good order.

• Battery

• Fuse

• System component-to-harness connections

SRS Operation Check

DIAGNOSTIC PROCEDURE 1

Checking SRS Operation Using “AIR BAG” Warning Lamp—User Mode

1. Turn the ignition switch from OFF to ON, and check that the air bag warning lamp blinks.

2. Compare the SRS air bag warning lamp blinking pattern with the examples.

SRS Air bag warning lamp examples

DIAGNOSTIC PROCEDURE 2

1. Connect CONSULT-III.

2. Diagnostic code is displayed on "SELF-DIAG [CURRENT]".

If no malfunction is detected on "SELF-DIAG [CURRENT]", but malfunction is detected in "SRS Operation Check" using the "AIR BAG" warning lamp, the following cases may exist: • "SELF-DIAG [PAST]" memory might not be erased.

• The SRS system malfunctions intermittently.

Perform DIAGNOSTIC PROCEDURE 4. Refer to SRC-14, "Self-Diagnosis Function (Without CONSULTIII)".

Trouble Diagnosis without CONSULT-III

DIAGNOSTIC PROCEDURE 6

Inspect SRS Malfunction Using "AIR BAG" Warning Lamp—Diagnosis Mode

NOTE: SRS will not enter Diagnosis mode if no malfunction is detected in User mode.

1. Turn ignition switch ON.

2. After “AIR BAG” warning lamp lights for 7 seconds, turn ignition switch OFF within 1 second.

3. Wait more than 3 seconds.

4. Repeat steps 1 to 3 two more times (3 times total).

5. Turn ignition switch ON.

SRS is now in Diagnosis mode. Refer to SRC-70, "Trouble Diagnosis without CONSULT-III".

CONSULT-III Function (AIR BAG)

CONSULT-III can display each diagnostic item using the diagnostic test modes shown following.

Self-Diagnosis Function (Without CONSULT-III)

• The reading of these results is accomplished using one of two modes —“User mode” and “Diagnosis mode”.

• After a malfunction is repaired, turn the ignition switch OFF for at least one second, then back ON. Diagnosis mode returns to the User mode. At that time, the self-diagnostic result is cleared.

HOW TO CHANGE SELF-DIAGNOSIS MODE

DIAGNOSTIC PROCEDURE 3

Final Check of SRS Using CONSULT-III—Diagnosis Mode

1. Connect CONSULT-III.

2. If no DTC is detected on “SELF-DIAG [CURRENT]”, repair of SRS is completed. Go to step 3.

If any DTC is detected on “SELF-DIAG [CURRENT]”, the malfunctioning part has not been repaired completely or another malfunctioning part is being detected. Perform DIAGNOSTIC PROCEDURE 2. Refer to SRC-12, "SRS Operation Check".

3. Touch “ERASE”.

NOTE: Touch “ERASE” to clear the memory of the malfunction (“SELF-DIAG [PAST]”).

If the memory of the malfunction in “SELF-DIAG [PAST]” is not erased, the User mode shows the system malfunction by the operation of the warning lamp even if the malfunction is repaired completely.

4. Touch “BACK” key of CONSULT-III. Touch “SELF-DIAG [PAST]”.

5. Check that no malfunction is detected on “SELF-DIAG [PAST]”.

6. Touch “BACK” key of CONSULT-III to return to User mode from Diagnosis mode.

7. Turn ignition switch OFF and then turn off and disconnect CONSULT-III.

8. Go to SRC-12, "SRS Operation Check".

DIAGNOSTIC PROCEDURE 4

Check SRS Repair History

1.CONSIDER POSSIBILITY THAT SELF-DIAGNOSTIC RESULT WAS NOT ERASED AFTER REPAIR

Check repair history of the SRS.

Have any previous repairs been made to the SRS? YES >> Self-diagnostic result “SELF-DIAG [PAST]” (previously stored in the memory) might not be erased after repair. Perform DIAGNOSTIC PROCEDURE 3. Refer to SRC-14, "Self-Diagnosis Function (Without CONSULT-III)".

NO >> Perform DIAGNOSTIC PROCEDURE 2. Refer to SRC-12, "SRS Operation Check".