Nissan CVT 診斷

Copy from http://forums.trinituner.com/forums/viewtopic.php?t=144013

TCM Self-diagnostic Procedure (No Tools) (Keywords: Nissan CVT, CVT Diagnostic, AT25)

Preparation
1. Turn ignition switch to “OFF” position.
2. Disconnect the throttle position switch harness connector.
3. Turn ignition switch to “ON” position.
4. Check continuity of the closed throttle position switch.Continuity should exist. (verify car is warmed up and throttle plate is closed)
5. Connect the throttle position switch harness connector.
6. Warm up the engine.
7. Turn the ignition switch from ON to OFF two more times, and then turn to OFF.
8. In the “P” position of the selector lever, turn the ignition switch ON, and verify that the CVT warning lamp turns on for about 2 seconds.
9. Turn the ignition switch OFF.
10. Press the brake pedal, and shift the selector lever to the “D” position.
11. Turn the ignition switch ON.
12. Release the brake, and shift the selector lever to the “L” position.
13. Fully depress both brake and accelerator pedals all the way to the floor. Without releasing the brake and accelerator pedals, shift the selector lever to the “D” position.
14. Read the display from the CVT warning lamp to complete the diagnosis.

ON BOARD DIAGNOSTIC SYSTEM DESCRIPTION

Judgement of Self-diagnosis Code via CVT or SPORT indicator lamp*

All judgement flickers are the same: All circuits that can be confirmed by self-diagnosis are OK.


1st judgement flicker is longer than others:

Secondary speed sensor (VEHICLE SPEED SENSOR CVT) circuit is short-circuited or disconnected.

⇒ Go to VEHICLE SPEED SENSOR CVT (SECONDARY SPEED SENSOR) (DTC: 0720), AT-62.


2nd judgement flicker is longer than others:

Primary speed sensor circuit is short-circuited or disconnected.

⇒ Go to PRIMARY SPEED SENSOR (DTC: 0715), AT-59.


3rd judgement flicker is longer than others:

Throttle position sensor circuit is short-circuited or disconnected.

⇒ Go to THROTTLE POSITION SENSOR (DTC: 1705), AT-79.


4th judgement flicker is longer than others:

Step motor circuit is short-circuited or disconnected.

⇒ Go to STEP MOTOR (DTC: 1777), AT-86.


5th judgement flicker is longer than others:

CVT fluid pressure sensor circuit is short-circuited or disconnected.

⇒ Go to CVT FLUID PRESSURE SENSOR (DTC: 1791), AT-94.


6th judgement flicker is longer than others:

Line pressure solenoid valve circuit is short-circuited or disconnected.

⇒ Go to LINE PRESSURE SOLENOID VALVE (DTC: 0745), AT-74.


7th judgement flicker is longer than others:

Lock up solenoid valve circuit is short-circuited or disconnected.

⇒ Go to TORQUE CONVERTER CLUTCH SOLENOID VALVE (DTC: 0740), AT-69.


8th judgement flicker is longer than others:

CVT fluid temperature sensor is disconnected or TCM power source circuit is damaged.

⇒ Go to CVT FLUID TEMPERATURE SENSOR (DTC: 0710) AND TCM POWER SOURCE, AT-54.


9th judgement flicker is longer than others:

Engine speed signal circuit is short-circuited or disconnected.

⇒ Go to ENGINE SPEED SIGNAL (DTC: 0725), AT-66.


10th judgement flicker is longer than others:

When “4th judgement flicker” and/or “6th judgement flicker” is displayed, inspect “STEP MOTOR (DTC: 1777)” and/or “LINE PRESSURE SOLENOID VALVE (DTC: 0745)”.

When neither “4th judgement flicker” nor “6th judgement flicker” are displayed, replace TCM.

⇒ Go to CVT SAFE FUNCTION, AT-99.