Nissan Altima (L32) 2007-2012 Service Manual: P1574 ASCD Vehicle speed sensor

Description

The ECM receives two vehicle speed signals via the CAN communication line. One is sent from combination meter, and the other is from TCM (Transmission control module). The ECM uses these signals for ASCD control.

Refer to EC-1090, "System Diagram" for ASCD functions.

DTC Logic

DTC DETECTION LOGIC

NOTE: • If DTC P1574 is displayed with DTC UXXXX, first perform the trouble diagnosis for DTC UXXXX.

• If DTC P1574 is displayed with DTC P0607, first perform the trouble diagnosis for DTC P0607. Refer to EC-1378, "DTC Logic".

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON.

3. Turn ignition switch OFF and wait at least 10 seconds.

>> GO TO 2.

2.PERFORM DTC CONFIRMATION PROCEDURE

1. Start engine (ESP switch OFF).

2. Drive the vehicle at more than 40 km/h (25 MPH).

CAUTION: Always drive vehicle at a safe speed.

If a road test is expected to be easier, it is unnecessary to lift the vehicle.

3. Check DTC.

Is DTC detected? YES >> Go to EC-1421, "Diagnosis Procedure".

NO >> INSPECTION END

Diagnosis Procedure

1.CHECK DTC WITH TCM

Check DTC with TCM. Refer to TM-117, "Diagnosis Description".

Is the inspection result normal? YES >> GO TO 2.

NO >> Perform trouble shooting relevant to DTC indicated.

2.CHECK DTC WITH “ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)”

Refer to BRC-223, "DTC No. Index".

Is the inspection result normal? YES >> GO TO 3.

NO >> Repair or replace malfunctioning part.

3.CHECK COMBINATION METER FUNCTION

Refer to MWI-95, "DTC Index".

>> INSPECTION END