Nissan Altima (L32) 2007-2012 Service Manual: P1723 CVT speed sensor function

Description

The vehicle speed sensor CVT [output speed sensor (secondary speed sensor)] detects the revolution of parking gear and generates a pulse signal. The pulse signal is sent to the TCM, which converts it into vehicle speed.

The input speed sensor (primary speed sensor) detects the primary pulley revolution speed and sends a signal to the TCM.

DTC Logic

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

CAUTION: Always drive vehicle at a safe speed.

NOTE: If “DTC CONFIRMATION PROCEDURE” has been previously performed, always turn ignition switch OFF.

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

1.CHECK DTC DETECTION

1. Turn ignition switch ON.

2. Select “DATA MONITOR”.

3. Start engine and maintain the following conditions for at least 5 consecutive seconds.

Is “P1723 CVT SPD SEN/FNCTN” detected? YES >> Go to TM-178, "Diagnosis Procedure".

NO >> Check intermittent incident. Refer to GI-42, "Intermittent Incident".

Diagnosis Procedure

1.CHECK STEP MOTOR FUNCTION

Perform “SELF-DIAG RESULTS” mode for “TRANSMISSION”.

Is “P1778 STEP MOTR/FNC” detected? YES >> Repair or replace damaged parts. Refer to TM-187, "DTC Logic".

NO >> GO TO 2.

2.CHECK OUTPUT SPEED SENSOR (SECONDARY SPEED SENSOR) SYSTEM

Check output speed sensor (secondary speed sensor) system. Refer to TM-138, "DTC Logic".

Is the inspection result normal?

YES >> GO TO 3.

NO >> Repair or replace damaged parts.

3.CHECK INPUT SPEED SENSOR (PRIMARY SPEED SENSOR) SYSTEM

Check input speed sensor (primary speed sensor) system. Refer to TM-135, "DTC Logic".

Is the inspection result normal? YES >> GO TO 4.

NO >> Repair or replace damaged parts.

4.CHECK ENGINE SPEED SIGNAL SYSTEM

Check engine speed signal system. Refer to TM-142, "DTC Logic".

Is the inspection result normal? YES >> GO TO 5.

NO >> Repair or replace damaged parts.

5.DETECT MALFUNCTIONING ITEMS

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

Is the inspection result normal? YES >> Replace TCM. Refer to TM-254, "Exploded View".

NO >> Repair or replace damaged parts.