Nissan Maxima Service and Repair Manual: P0703 brake switch B

Description

BCM detects ON/OFF state of the stop lamp switch and transmits the data to the TCM via CAN communication by converting the data to a signal.

DTC Logic

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

CAUTION: Always drive vehicle at a safe speed.

NOTE: Immediately after performing any "DTC CONFIRMATION PROCEDURE", always turn ignition switch OFF.

Then wait at least 10 seconds before performing the next test.

1.CHECK DTC DETECTION

With CONSULT

1.  Turn ignition switch ON.
2.  Start engine.
3.  Drive vehicle for at least 3 consecutive seconds.
4.  Perform "Self Diagnostic Results" in "TRANSMISSION".

Diagnosis Procedure

Regarding Wiring Diagram information, refer to TM-126, "Wiring Diagram".

1.CHECK STOP LAMP SWITCH CIRCUIT

1.  Check and adjust the installation position of stop lamp switch. Refer to BR-14, "Inspection and Adjustment".
2.  Disconnect BCM connector.
3.  Check voltage between BCM vehicle side harness connector terminal and ground.

2.CHECK HARNESS BETWEEN STOP LAMP SWITCH AND BCM (PART 1)

1.  Disconnect stop lamp switch connector.
2.  Check continuity between stop lamp switch vehicle side harness connector terminal and BCM vehicle side harness connector terminal.

3.CHECK HARNESS BETWEEN STOP LAMP SWITCH AND BCM (PART 2)

Check continuity between BCM vehicle side harness connector terminal and ground.

4.CHECK STOP LAMP SWITCH

Check stop lamp switch. Refer to TM-48, "Component Inspection (Stop Lamp Switch)".

5.CHECK BCM

With CONSULT

1.  Turn ignition switch OFF.
2.  Connect BCM connector.
3.  Turn ignition switch ON.
4.  Select "BRAKE SW 1" in "Data Monitor" in "BCM" and verify the proper operation of ON/OFF. Refer to BCS-41, "Reference Value".

6.DETECT MALFUNCTIONING ITEMS

Check TCM connector pin terminals for damage or loose connection with harness connector.

Component Inspection (Stop Lamp Switch)

1.CHECK STOP LAMP SWITCH

Check continuity between stop lamp switch connector terminals.