P0720

DTC P0720 VEHICLE SPEED SENSOR-A/T (REVOLUTION SENSOR)







Description
The revolution sensor detects the revolution of the output shaft parking pawl lock gear and emits a pulse signal. The pulse signal is sent to the TCM which converts it into vehicle speed.

TCM TERMINALS AND REFERENCE VALUE:

ON BOARD DIAGNOSIS LOGIC:

DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PROCEDURE

CAUTION: Always drive vehicle at a safe speed.
Be careful not to rev engine into the red zone on the tachometer.

NOTE: If "DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE" has been previously conducted, always turn ignition switch OFF and wait at least 5 seconds before conducting the next test. After the repair, perform the following procedure to confirm the malfunction is eliminated.










With CONSULT-II
1. Turn ignition switch ON and select "DATA MONITOR" mode for "A/T" with CONSULT-II.
2. Drive vehicle and check for an increase of "VHCL/S SE-MTR" value.
If the check result is NG, go to "DTC Vehicle Speed Sensor-MTR; Diagnostic Procedure". Vehicle Speed Sensor MTR
If the check result is OK, go to following step.

3. Select "DATA MONITOR" mode for "ENGINE" with CONSULT-II.
4. Start engine and maintain the following conditions for at least 5 consecutive seconds.

VHCL SPEED SE:.....30 km/h (19 MPH) or more
THRTL POS SEN:.....More than 1.2V
Selector lever:.......D position (O/D ON)
Driving condition:.....Driving the vehicle uphill (increased engine load) will help maintain the driving conditions required for this test.

If the check result is NG, go to "P1705; Diagnostic Procedure" P1705
If the check result is OK, go to following step.

5. Maintain the following conditions for at least 5 consecutive seconds.
CMPS-RPM (REF):.........3,500 rpm or more
THRTL POS SEN ............More than 1.2V
Selector lever:...........D position (O/D ON)
Driving condition:.............Driving the vehicle uphill (increased engine load) will help maintain the driving conditions required for this test.


With GST
Follow the procedure "With CONSULT-II".

AT - VSSA/T:

Diagnostic Procedure
1. CHECK REVOLUTION SENSOR

OK or NG?

OK >> GO TO 2
NG >> Repair or replace revolution sensor.

2. CHECK INPUT SIGNAL

With CONSULT-II
1. Start engine.
2. Select "TCM INPUT SIGNALS" in "DATA MONITOR" mode for "A/T" with CONSULT-II.







3. Read out the value of "VHCL/S SE-A/T" while driving.
Check the value changes according to driving speed.


Without CONSULT-II
1. Start engine.







2. Check voltage between TCM connector M78 terminal 29 (B/R) and ground while driving. (Measure with AC range.)

Voltage:
At 0 km/h (0 MPH) 0V
At 30 km/h (19 MPH) 1V or more
(Voltage rises gradually in response to vehicle speed.)

OK or NG?

OK >>GO TO 3

NG >> Check the following items:
- Harness for short or open between TCM and revolution sensor (Main harness)
- Harness for short or open between revolution sensor and ECM (Main harness)
- Ground circuit for ECM

3. CHECK DTC
Perform Diagnostic Trouble Code (DTC) confirmation procedure.
OK or NG?

OK >> INSPECTION END.

NG >>
1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.




REVOLUTION SENSOR / Component Inspection
For removal, refer to "Revolution Sensor Replacement"










Check resistance between terminals 1 and 2.