Nissan Maxima Service and Repair Manual: DTC/circuit diagnosis

• U1000 CAN comm circuit

Description CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN-H, CAN-L) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only. DTC Logic DTC DETECTION LOGIC Diagnosis Procedure 1.

• U1010 control unit (CAN)

DTC Logic DTC DETECTION LOGIC U1200 AV CONTROL UNIT DTC Logic U1201 AV CONTROL UNIT DTC Logic U1202 AV CONTROL UNIT DTC Logic

• U1204 AV control unit

DTC Logic Diagnosis Procedure 1.PERFORM THE SELF-DIAGNOSIS Delete the "self-diagnosis" results of "MULTI AV". Turn ignition switch OFF. Turn ignition switch ON. Perform the self-diagnosis again.

• U1205 AV control unit

DTC Logic Diagnosis Procedure 1.PERFORM THE SELF-DIAGNOSIS Delete the "self-diagnosis" results of "MULTI AV". Turn ignition switch OFF. Turn ignition switch ON. Perform the self-diagnosis again. Check that the DTC is detected again.

• U1206 AV control unit

DTC Logic Diagnosis Procedure 1.PERFORM THE SELF-DIAGNOSIS Delete the "self-diagnosis" results of "MULTI AV". Turn ignition switch OFF. Turn ignition switch ON. Perform the self-diagnosis again.

• U1207 AV control unit

DTC Logic Diagnosis Procedure 1.PERFORM THE SELF-DIAGNOSIS Delete the "self-diagnosis" results of "MULTI AV". Turn ignition switch OFF. Turn ignition switch ON. Perform the self-diagnosis again. Check that the DTC is detected again.

• U121D AV control unit

DTC Logic Diagnosis Procedure 1.CHECK PLAYBACK OF A DISK (CD) U121E AV CONTROL UNIT DTC Logic Diagnosis Procedure 1.CHECK PLAYBACK OF A DISK (CD) U1225 AV CONTROL UNIT DTC Logic DTC DETECTION LOGIC U1227 AV CONTROL UNIT DTC Logic Diagnosis Procedure 1.

• U122A AV control unit

DTC Logic Diagnosis Procedure 1.PERFORM THE SELF-DIAGNOSIS When U122A is detected, write configuration data with "MULTI AV" of CONSULT.

• U1232 steering angle sensor

DTC Logic Diagnosis Procedure 1.ADJUST THE PREDICTIVE COURSE LINE CENTER POSITION OF THE STEERING ANGLE SENSOR When U1232 is detected, adjust the predictive course line center position of the steering angle sensor.

• U1243 display unit

DTC Logic Diagnosis Procedure 1.CHECK DISPLAY UNIT POWER SUPPLY AND GROUND CIRCUIT Check display unit power supply and ground circuit 2.CHECK CONTINUITY OF COMMUNICATION CIRCUIT Turn ignition switch OFF. Disconnect display unit connector M142 and AV control unit connector M163. Check continuity between display unit harness connector M142 (A) terminals 9, 10 and AV control unit harness connector M163 (B) terminals 45 and 61 Check continuity between display unit harness connector M142 (A) terminals 9, 10 and ground. 3.CHECK COMMUNICATION SIGNAL Connect display unit connector and AV control unit connector. Turn ignition switch ON.

• U1244 GPS antenna

DTC Logic Diagnosis Procedure 1.GPS ANTENNA CHECK Inspect GPS antenna and antenna feeder for damage or poor connection. 2.CHECK AV CONTROL UNIT VOLTAGE Turn ignition switch ON. Check voltage between AV control unit connector M165 terminal 105 and ground.

• U1263 USB

DTC Logic Diagnosis Procedure 1.CHECK USB HARNESS Visually check USB harness.

• U1300 AV comm circuit

Description U1300 is indicated when malfunction occurs in communication signal of multi AV system. Indicated simultaneously, without fail, with the malfunction of control units connected to AV control unit with communication line. Determine the possible malfunction cause from the table below.

• Power supply and ground circuit

AV CONTROL UNIT AV CONTROL UNIT : Diagnosis Procedure 1.CHECK FUSES Check that the following AV control unit fuses are not blown. 2.POWER SUPPLY CIRCUIT CHECK Disconnect AV control unit connectors M160 and M163. Check voltage between the AV control unit connectors M160 and M163 and ground. 3.GROUND CIRCUIT CHECK Turn ignition switch OFF. Check continuity between AV control unit harness connector M160 and ground. DISPLAY UNIT DISPLAY UNIT : Diagnosis Procedure 1.CHECK FUSES Check that the following display unit fuses are not blown. 2.CHECK POWER SUPPLY CIRCUIT Turn ignition switch to ACC. Check voltage between display unit harness connector M142 and ground 3.

• RGB digital image signal circuit

Description Transmit the image displayed with AV control unit with RGB digital image signal to the display unit. Diagnosis Procedure 1.CHECK CONTINUITY RGB DIGITAL IMAGE SIGNAL CIRCUIT Turn ignition switch OFF. Disconnect display unit connector M151 and AV control unit connector M161. Check continuity between display unit harness connector M151 (A) terminals 27, 28 and AV control unit harness connector M161 (B) terminals 23 and 24. Check continuity between display unit harness connector M151 (A) terminals 27, 28 and ground. 2.CHECK RGB DIGITAL IMAGE SIGNAL Connect display unit connector M151 and AV control unit connector M161. Turn ignition switch ON.

• Composite image signal circuit

Description AV control unit transmits the playback DVD image signal and AUX image signal to the display unit. Diagnosis Procedure 1.CHECK CONTINUITY COMPOSITE IMAGE SIGNAL CIRCUIT Turn ignition switch OFF. Disconnect AV control unit connector M163 and display unit connector M142. Check continuity between AV control unit connector M163 (A) terminal 40 and display unit connector M142 (B) terminal 18. Check continuity between AV control unit connector M163 (A) terminal 40 and ground. 2.CHECK AUX COMPOSITE SIGNAL Connect AV control unit connector M163 and display unit connector M142. Turn ignition switch ON. Check signal between AV control unit harness connector M163 terminal 40 and ground.

• Aux image signal circuit

Description Transmits the image signal of AUX device from auxiliary input jacks to AV control unit. AV control unit transmits the image signal that is input to the display unit. Diagnosis Procedure 1.CHECK CONTINUITY AUX IMAGE SIGNAL CIRCUIT Turn ignition switch OFF. Disconnect auxiliary input jack connector M209 and AV control unit connector M164. Check continuity between auxiliary input jack harness connector M209 (A) terminal 7 and AV control unit harness connector M164 (B) terminal 76 Check continuity between auxiliary input jack harness connector M209 (A) terminal 8 and ground. 2.CHECK AUX IMAGE SIGNAL Connect auxiliary input jack connector M209 and AV control unit connector M164.

• Disk eject signal circuit

Description The eject signal is output to AV control unit when the eject switch of A/C and AV switch assembly is pressed. Diagnosis Procedure 1.CHECK CONTINUITY DISK EJECT SIGNAL CIRCUIT Turn ignition switch OFF. Disconnect A/C and AV switch assembly connector M98 and AV control unit connector M164. Check continuity between A/C and AV switch assembly connector M98 (A) terminal 14 and AV control unit harness connector M164 (B) terminal 82. Check continuity between A/C and AV switch assembly connector M98 (A) terminal 14 and ground. 2.CHECK AV CONTROL UNIT VOLTAGE Connect A/C and AV switch assembly connector M98 and AV control unit connector M164. Turn ignition switch ON.

• Microphone signal circuit

Description Voice signals are transmitted from the microphone to the AV control unit using the microphone signal circuits. Diagnosis Procedure 1.CHECK HARNESS BETWEEN AV CONTROL UNIT AND MICROPHONE Turn ignition switch OFF. Disconnect AV control unit connector and microphone connector. Check continuity between AV control unit harness connector M163 (A) and microphone harness connector R7 (B). Check continuity between AV control unit harness connector M163 (A) and ground. 2.CHECK MICROPHONE POWER SUPPLY Connect AV control unit connector and microphone connector. Turn ignition switch ON. Check voltage between microphone harness connector R7 terminal 4 and ground. 3.

• AMP on signal circuit

Description When the audio system is turned on, a voltage signal is supplied from the AV control unit to the BOSE speaker amp. When this signal is received, the BOSE speaker amp. will turn on. Diagnosis Procedure 1.CHECK AMP ON SIGNAL (BOSE SPEAKER AMP) Turn audio system ON. Check voltage between BOSE speaker amp. harness connector B109 terminal 20 and ground. 2.

• Front door speaker

Description The AV control unit sends audio signals to the BOSE speaker amp. The BOSE speaker amp. amplifies the audio signals before sending them to the front door speakers using the audio signal circuits. Diagnosis Procedure 1.CONNECTOR CHECK Check the AV control unit, BOSE speaker amp. and speaker connectors for the following: Proper connection Damage Disconnected or loose terminals 2.HARNESS CHECK Disconnect BOSE speaker amp. connector B109 and suspect speaker connector. Check continuity between BOSE speaker amp. harness connector B109 (A) and suspect speaker harness connector (B). Check continuity between BOSE speaker amp. harness connector B109 (A) and ground. 3.

• Tweeter

Description The AV control unit sends audio signals to the BOSE speaker amp. The BOSE speaker amp. amplifies the audio signals before sending them to the tweeters using the audio signal circuits. Diagnosis Procedure 1.CONNECTOR CHECK Check the AV control unit, BOSE speaker amp. and speaker connectors for the following: Proper connection Damage Disconnected or loose terminals 2.HARNESS CHECK Disconnect BOSE speaker amp. connector B110 and suspect tweeter connector. Check continuity between BOSE speaker amp. harness connector B110 (A) and suspect tweeter harness connector (B). Check continuity between BOSE speaker amp. harness connector B110 (A) and ground. 3.

• Center speaker

Description The AV control unit sends audio signals to the BOSE speaker amp. The BOSE speaker amp. amplifies the audio signals before sending them to the center speaker using the audio signal circuits. Diagnosis Procedure 1.CONNECTOR CHECK Check the AV control unit, BOSE speaker amp. and speaker connectors for the following: Proper connection Damage Disconnected or loose terminals 2.HARNESS CHECK Disconnect BOSE speaker amp. connector B109 and center speaker connector M130. Check continuity between BOSE speaker amp. harness connector B109 (A) and center speaker harness connector M130 (B). Check continuity between BOSE speaker amp. harness connector B109 (A) and ground. 3.

• Rear door speaker

Description The AV control unit sends audio signals to the BOSE speaker amp. The BOSE speaker amp. amplifies the audio signals before sending them to the rear door speakers using the audio signal circuits. Diagnosis Procedure 1.CONNECTOR CHECK Check the AV control unit, BOSE speaker amp. and speaker connectors for the following: Proper connection Damage Disconnected or loose terminals 2.HARNESS CHECK Disconnect BOSE speaker amp. connectors B109, B110 and suspect speaker connector. Check continuity between BOSE speaker amp. harness connectors B109 (A) and B110 (B) and suspect speaker harness connector (C). Check continuity between BOSE speaker amp.

• Subwoofer

Description The AV control unit sends audio signals to the BOSE speaker amp. The BOSE speaker amp. amplifies the audio signals before sending them to the subwoofers using the audio signal circuits. Diagnosis Procedure 1.CONNECTOR CHECK Check the AV control unit, BOSE speaker amp. and subwoofer connectors for the following: Proper connection Damage Disconnected or loose terminals 2.HARNESS CHECK Disconnect BOSE speaker amp. connector B110 and suspect rear subwoofer connector. Check continuity between BOSE speaker amp. harness connector B110 (A) and suspect rear subwoofer harness connector (B). Check continuity between BOSE speaker amp. harness connector B110 (A) and ground. 3.

• Steering switch

Description When one of the steering wheel audio control switches is pushed, the resistance in the steering wheel audio control switch circuit changes, depending on which button is pushed. Diagnosis Procedure 1.CHECK STEERING WHEEL AUDIO CONTROL SWITCH RESISTANCE Turn ignition switch OFF. Disconnect steering wheel audio control switch connector M88. Check resistance between steering switch connector terminals. 2.CHECK HARNESS BETWEEN COMBINATION SWITCH (SPIRAL CABLE) AND AV CONTROL UNIT Disconnect AV control unit connector M160 and combination switch (spiral cable) connector M30.