Automatic Transaxle: Overview Nissan Maxima A34

SYSTEM 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 line, CAN L line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.

For details, refer to CAN COMMUNICATION .

Scheme 9

1. The pressure control solenoid valve A controls linear line pressure by control signal from TCM and line pressure for clutches and brakes to reduce shift shock.
2. This pressure control solenoid valve A controls the pressure regulator valve as the signal pressure and adjusts the pressure of the operating oil discharged from the oil pump to the line pressure most appropriate to the driving state.

DESCRIPTION

The MIL is located on the instrument panel.

Scheme 10

1. The MIL will light up when the ignition switch is turned "ON" without the engine running. This is a bulb check. If the MIL does not light up, refer to «WARNING LAMPS»(ref-233665-S40203573012006052600000) or see «MALFUNCTION INDICATOR LAMP (MIL)»(ref-233647-S20189250822006052600000) .
2. When the engine is started, the MIL should go off. If the MIL remains on, the on board diagnostic system has detected an engine system malfunction.

1. The road test inspects overall performance of the A/T and analyzes possible malfunction causes.
2. The road test is perform in the following three stages.

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1. Check before engine is started. Refer to «CHECK BEFORE ENGINE IS STARTED»(ref-233658-S34186835432006052600000) .
2. Check at idle. Refer to «CHECK BEFORE ENGINE IS STARTED»(ref-233658-S34186835432006052600000) .
3. Cruise test Inspect all the items from Part 1 to Part 3. Refer to «CRUISE TEST - PART 1»(ref-233658-S03113890602006052600000) , «CRUISE TEST - PART 2»(ref-233658-S37443881382006052600000) and «CRUISE TEST - PART 3»(ref-233658-S23851303172006052600000) . Before beginning the road test, check the test procedure and inspection items. Test all inspection items until the symptom is uncovered. Diagnose NG items when all road tests are complete.

Operation procedure

1. Perform "CONSULT-II SETTING PROCEDURE". Refer to «CONSULT-II SETTING»(ref-233658-S00109389242006052600000) .
2. Touch "DATA MONITOR". NOTE: When malfunction is detected, CONSULT-II performs REAL-TIME DIAGNOSIS. Also, any malfunction detected while in this mode will be displayed at real time.

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Note. Approximately 10 seconds after the operation is begun, "TEST IS STOPPED" will be displayed.

As a method for locating the suspect system, when the self-diagnostics start signal is input, the memory for the malfunction location is output and the A/T CHECK indicator lamp flashes to display the corresponding DTC.

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 malfunction 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 line, CAN L line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.

The vehicle speed sensor MTR signal is transmitted from unified meter and A/C amp. to TCM by CAN communication line. The signal functions as an auxiliary device to the revolution sensor when it is malfunctioning. The TCM will then use the vehicle speed sensor MTR signal.

The TCM consists of a microcomputer and connectors for signal input and output and for power supply. The TCM controls the A/T.

Scheme 17

1. The park/neutral position (PNP) switch includes a transmission position switch.
2. The transmission range switch detects the selector lever position and sends a signal to the TCM.
3. TCM judges the selector lever position by the park/neutral position (PNP) switch signal. TCM SPECIFICATION Selector lever PNP switch A PNP switch B PNP switch C PNP switch PA PNP switch PN P ON OFF OFF ON ON R ON ON OFF OFF OFF N OFF ON OFF ON ON D OFF ON ON OFF OFF

The A/T fluid temperature sensor detects the A/T fluid temperature and sends a signal to the TCM.

The A/T fluid temperature sensor detects the A/T fluid temperature and sends a signal to the TCM.

The engine speed signal is sent from the ECM to the TCM.

1. This malfunction will not be detected while the A/T CHECK indicator lamp is indicating another self-diagnosis malfunction.
2. This malfunction is detected when the torque converter clutch does not lock up as instructed by the TCM. This is not caused by electrical malfunction (circuits open or shorted) but by mechanical malfunction such as control valve sticking, improper solenoid valve operation, malfunctioning oil pump or torque converter clutch, etc.

1. Shift solenoid valves are installed directly in control valve body. The shift solenoid valves operates of ON and OFF by the control signal from TCM. Combinations of 5 shift solenoid valves, A, B, C, D and E, shifts gear positions.
2. The shift solenoid valve A is a normally open, ON-OFF type solenoid. GEAR POSITION SPECIFICATION Gear position D 1 , M 1 D 2 , M 2 D 3 , M 3 D 4 , M 4 D 5 , M 5 Reverse Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) OFF (Open) OFF (Open) OFF (Open)

1. Shift solenoid valves are installed directly in control valve body. The shift solenoid valves operates of ON and OFF by the control signal from TCM. Combinations of 5 shift solenoid valves, A, B, C, D and E, shifts gear positions.
2. The shift solenoid valve B is a normally closed, ON-OFF type solenoid. GEAR POSITION SPECIFICATION Gear position D 1 , M 1 D 2 , M 2 D 3 , M 3 D 4 , M 4 D 5 , M 5 Reverse Shift solenoid valve B ON (Open) OFF (Closed) OFF (Closed) OFF (Closed) ON (Open) OFF (Closed)

1. Shift solenoid valves are installed directly in control valve body. The shift solenoid valves operates of ON and OFF by the control signal from TCM. Combinations of 5 shift solenoid valves, A, B, C, D and E, shifts gear positions.
2. The shift solenoid valve C is a normally closed, ON-OFF type solenoid. GEAR POSITION SPECIFICATION Gear position D 1 , M 1 D 2 , M 2 D 3 , M 3 D 4 , M 4 D 5 , M 5 Reverse Shift solenoid valve C ON (Open) ON (Open) ON (Open) OFF (Closed) OFF (Closed) ON (Open)

1. This malfunction will not be detected while the A/T CHECK indicator lamp is indicating another self-diagnosis malfunction.
2. This is not caused by electrical malfunction (circuits open or shorted) but by mechanical malfunction such as control valve sticking, improper solenoid valve operation, etc.
3. Shift solenoid valves are installed directly in control valve body. The shift solenoid valves operates of ON and OFF by the control signal from TCM. Combinations of 5 shift solenoid valves, A, B, C, D and E, shifts gear positions.
4. The shift solenoid valve C is a normally closed, ON-OFF type solenoid.

GEAR POSITION SPECIFICATIONS

1. Shift solenoid valves are installed directly in control valve body. The shift solenoid valves operates of ON and OFF by the control signal from TCM. Combinations of 5 shift solenoid valves, A, B, C, D and E, shifts gear positions.
2. The shift solenoid valve D is a normally open, ON-OFF type solenoid. GEAR POSITION SPECIFICATIONS Gear position D 1 , M 1 D 2 , M 2 D 3 , M 3 D 4 , M 4 D 5 , M 5 Reverse Shift solenoid valve D OFF (Open) OFF (Open) ON (Closed) ON (Closed) ON (Closed) OFF (Open)

1. Shift solenoid valves are installed directly in control valve body. The shift solenoid valves operates of ON and OFF by the control signal from TCM. Combinations of 5 shift solenoid valves, A, B, C, D and E, shifts gear positions.
2. The shift solenoid valve E is a normally closed, ON-OFF type solenoid. GEAR POSITION SPECIFICATIONS Gear position D 1 M 1 D 2 , M 2 D 3 , M 3 D 4 , M 4 D 5 , M 5 Reverse Shift solenoid valve E OFF (Closed) ON (Open) OFF (Closed) OFF (Closed) OFF (Closed) OFF (Closed) ON (Open) NOTE: The condition of shift solenoid valve E is ON (Open) with shifting D 2 --> D 3 and D 3 --> D 4 .

1. This malfunction will not be detected while the A/T CHECK indicator lamp is indicating another self-diagnosis malfunction.
2. This malfunction is detected when the A/T does not shift as instructed by the TCM. This is not caused by electrical malfunction (circuits open or shorted) but by mechanical malfunction such as control valve sticking, improper solenoid valve operation, etc.

Manual mode switch is installed in A/T device. It sends manual mode switch, shift up and shift down switch signals to TCM.

TCM sends the switch signals to unified meter and A/C amp. by CAN communication line. Then manual mode switch position is indicated on the A/T indicator. For inspection, refer to POSITION INDICATOR .

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When the power supply to the TCM is cut "OFF", for example because the battery is removed, and the self diagnostics memory function stops, malfunction is detected.

This DTC is displayed with other DTCs regarding ECM. Perform the trouble diagnosis for other DTCs displayed. Refer to TROUBLE DIAGNOSIS .

When this DTC is detected, lock-up operation and learning control are canceled.

1. Park/neutral position (PNP) switch The park/neutral (PNP) switch assembly includes a transmission range switch. The transmission range switch detects the selector lever position and sends a signal to the TCM.
2. Stop lamp switch signal Detects the brake pedal state (stop lamp switch is ON or OFF) and sends a signal via CAN communication line to the TCM.
3. Closed throttle position signal ECM judges throttle opening based on a signal from accelerator pedal position sensor, and sends the signal via CAN communication line to TCM.

Scheme 19

1. CHECK PARK/NEUTRAL POSITION (PNP) SWITCH CIRCUIT Check the park/neutral position (PNP) switch circuit. Refer to «DTC P0705 PARK/NEUTRAL POSITION SWITCH»(ref-233658-S12835449912006052600000) . OK or NG OK: GO TO 2 . NG: Repair or replace damaged parts.
2. CHECK STOP LAMP SWITCH CIRCUIT Perform self-diagnosis for ABS actuator and electric unit (control unit). Refer to «TROUBLE DIAGNOSIS»(ref-233669-S18639308772006052600000) (with ABS), «TROUBLE DIAGNOSIS»(ref-233669-S23745466562006052600000) (with TCS/ABS) or «TROUBLE DIAGNOSIS»(ref-233669-S21199278182006092900000) (with VDC/TCS/ABS). OK or NG OK: GO TO 3 . NG: Repair or replace damaged parts.
3. CHECK CLOSED THROTTLE POSITION SIGNAL CIRCUIT Perform self-diagnosis for ECM. Refer to «EMISSION-RELATED DIAGNOSTIC INFORMATION»(ref-233647-S40440847742006052600000) . OK or NG OK: GO TO 4 . NG: Repair or replace damaged parts.
4. CHECK DATA MONITOR (WITH CONSULT-II) With CONSULT-II Turn ignition switch "ON". (Do not start engine.) Select "A/T" with "DATA MONITOR" mode in CONSULT-II. Depress or release accelerator pedal and read out ON/OFF signaling action of the "CLSD THL POS". Depress or release brake pedal and read out ON/OFF signaling action of the "BRAKE SW". OK or NG OK: GO TO 7 . NG: GO TO 5 .
5. CHECK TCM Check TCM input/output signal. Refer to «TCM INPUT/OUTPUT SIGNAL REFERENCE VALUES»(ref-233658-S42079046452006052600000) . If NG, recheck TCM pin terminals for damage or loose connection with harness connector. OK or NG OK: GO TO 6 . NG: Repair or replace damaged parts.
6. CHECK CAN COMMUNICATION LINE Check the CAN communication line. Refer to «DTC U1000 CAN COMMUNICATION LINE»(ref-233658-S17861994372006052600000) . OK or NG OK: GO TO 7 . NG: Repair or replace damaged parts.
7. CHECK SYMPTOM Check again. OK or NG OK: INSPECTION END NG: Replace the TCM.

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1. The electrical key interlock mechanism also operates as a shift lock: With the key switch turned to ON, the selector lever cannot be shifted from "P" (parking) to any other position unless the brake pedal is depressed. With the key removed, the selector lever cannot be shifted from "P" to any other position. The key cannot be removed unless the selector lever is placed in "P".
2. The shift lock and key interlock mechanisms are controlled by the ON-OFF operation of the shift lock solenoid and by the operation of the rotator and slider located inside the key cylinder.

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