Nissan Maxima Service and Repair Manual: DTC/circuit diagnosis

• Power supply and ground circuit

BCM BCM : Diagnosis Procedure 1. CHECK FUSE AND FUSIBLE LINK Check if the following BCM fuses or fusible link are blown. 2. CHECK POWER SUPPLY CIRCUIT Turn ignition switch OFF. Disconnect BCM. Check voltage between BCM harness connector and ground. 3. CHECK GROUND CIRCUIT Check continuity between BCM harness connector and ground. BCM : Special Repair Requirement 1. REQUIRED WORK WHEN REPLACING BCM Initialize control unit. POWER WINDOW MAIN SWITCH POWER WINDOW MAIN SWITCH : Diagnosis Procedure 1. CHECK POWER SUPPLY CIRCUIT Turn ignition switch ON. Check voltage between main power window and door lock/ unlock switch connectors D7 (A) terminal 10 and D8 (B) terminal 19 and ground. 2.

• Rear power window switch

Description BCM supplies power. Rear power window motor operates when rear power window switch is activated. Component Function Check Rear Power Window Switch 1. CHECK REAR POWER WINDOW MOTOR FUNCTION Check that rear power window motor operates from rear power window switch. Diagnosis Procedure 1. CHECK REAR POWER WINDOW SWITCH Check rear power window switch 2. CHECK REAR POWER WINDOW SWITCH INPUT SIGNAL Turn ignition switch OFF. Disconnect rear power window switch connector. Turn ignition switch ON. Check voltage between rear power window switch connector and ground. 3. CHECK HARNESS CONTINUITY (REAR POWER WINDOW SWITCH LH) Turn ignition switch OFF.

• Power window motor

DRIVER SIDE DRIVER SIDE : Description Door glass moves UP/DOWN by receiving the signal from main power window and door lock/unlock switch. DRIVER SIDE : Component Function Check 1. CHECK FRONT POWER WINDOW MOTOR LH Check that front power window motor LH operates with main power window and door lock/unlock switch. DRIVER SIDE : Diagnosis Procedure 1. CHECK FRONT POWER WINDOW MOTOR LH Check front power window motor LH 2. CHECK MAIN POWER WINDOW AND DOOR LOCK/UNLOCK SWITCH OUTPUT SIGNAL Disconnect front power window motor LH connector. Turn ignition switch ON. Check voltage between front power window motor LH connector D9 terminals 1, 2 and ground. 3.

• Encoder

DRIVER SIDE DRIVER SIDE : Description Detects condition of the front power window motor LH operation and transmits to main power window and door lock/unlock switch as pulse signal. DRIVER SIDE : Component Function Check 1. CHECK ENCODER OPERATION Check that front door glass LH performs AUTO open/close operation normally when operating main power window and door lock/unlock switch. DRIVER SIDE : Diagnosis Procedure 1.CHECK ENCODER OPERATION Turn ignition switch ON. Check signal between main power window and door lock/unlock switch connector D7 terminals 9, 13 and ground with oscilloscope. 2.

• Door switch

Description Detects front door open/close condition. Component Function Check 1.CHECK FUNCTION With CONSULT Check front door switches DOOR SW-DR and DOOR SW-AS in Data Monitor mode with CONSULT. Diagnosis Procedure 1.CHECK FRONT DOOR SWITCH INPUT SIGNAL Turn ignition switch OFF. Check signal between BCM connector and ground with oscilloscope. 2.CHECK FRONT DOOR SWITCH CIRCUIT Disconnect BCM connector. Check continuity between BCM connector and front door switch connector. Check continuity between BCM connector and ground. 3.CHECK FRONT DOOR SWITCH 4.CHECK INTERMITTENT INCIDENT Component Inspection 1.CHECK FRONT DOOR SWITCH Turn ignition switch OFF. Disconnect front door switch connector.

• Door key cylinder switch

Description The main power window and door lock/unlock switch detects condition of the door key cylinder switch and transmits to BCM as the LOCK or UNLOCK signal. Component Function Check 1.CHECK DOOR KEY CYLINDER SWITCH INPUT SIGNAL Check KEY CYL UN-SW, KEY CYL UN-SW in "DATA MONITOR" mode for "POWER DOOR LOCK SYSTEM" with CONSULT. Diagnosis Procedure 1.CHECK DOOR KEY CYLINDER SWITCH INPUT SIGNAL Turn ignition switch ON. Check voltage between main power window and door lock/ unlock switch connector and ground 2.CHECK DOOR KEY CYLINDER SIGNAL CIRCUIT Turn ignition switch OFF.

• Power window serial link

POWER WINDOW MAIN SWITCH POWER WINDOW MAIN SWITCH : Description Main power window and door lock/unlock switch, power window and door lock/unlock switch RH and BCM communicate via the power window serial link. The keyless power window down signal is transmitted from BCM to main power window and door lock/ unlock switch and power window and door lock/unlock switch RH. The following signals are transmitted from main power window and door lock/unlock switch to power window and door lock/unlock switch RH: Front door window RH operation Power window control by key cylinder switch Power window lock switch Retained accessory power operation POWER WINDOW MAIN SWITCH : Component Function Check 1.

• Power window lock switch

Component Function Check 1. CHECK POWER WINDOW LOCK Activate the power window lock switch and verify that the front power window RH, rear power window LH and rear power window RH are inoperative. Component Inspection 1. CHECK POWER WINDOW LOCK SWITCH Disconnect main power window and door lock/unlock switch connectors. Check continuity between main power window and door lock/unlock switch (lock operation). Check continuity between main power window and door lock/unlock switch (unlock operation). Special Repair Requirement 1. PERFORM INITIALIZATION PROCEDURE Perform initialization procedure. 2.