DTC P0720[FN4A-EL]

id0502a1809800


ZY, LF

DTC P0720

Vehicle speed sensor (VSS) circuit malfunction
DETECTION CONDITION
•  Vehicle speed signal is not input after the following conditions are met and 4.5 s or more have passed.
―  D range switch ON
―  Engine coolant temperature 60 °C {140 °F} or more
―  Turbine speed 1,500 rpm or more
Diagnostic support note:
•  This is a continuous monitor (CCM).
•  The MIL illuminates if the PCM detects the above malfunction conditions during the first drive cycle.
•  The PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
•  FREEZE FRAME DATA is available.
•  The AT warning light illuminates.
•  The DTC is stored in the PCM memory.
POSSIBLE CAUSE
•  VSS malfunction
•  Main relay malfunction
•  Open circuit in wiring harness between VSS terminal B and PCM terminal 1AX (ZY)/1J (LF)
•  Short to ground in wiring harness between VSS terminal B and PCM terminal 1AX (ZY)/1J (LF)
•  Open circuit in wiring harness between VSS terminal A and main relay
•  Short to ground in wiring harness between VSS terminal A and main relay
•  Open circuit in wiring harness between VSS terminal C and body ground
•  Damaged connectors between VSS and PCM
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
•  Has the FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT VSS CONNECTOR FOR POOR CONNECTION
•  Turn the ignition switch to the LOCK position.
•  Disconnect the VSS connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is the connection normal?
Yes
Go to the next step.
No
Repair or replace the pin or connector, then go to Step 11.
4
INSPECT VSS POWER CIRCUIT FOR OPEN CIRCUIT
•  Verify that the VSS connector is disconnected.
•  Turn the ignition switch to the ON position (engine off).
•  Inspect the voltage between VSS terminal A (wiring harness-side) and ground.
•  Is the voltage B+?
Yes
Go to Step 6.
No
Go to the next step.
5
INSPECT VSS POWER CIRCUIT FOR SHORT TO GROUND
•  Turn the ignition switch to the LOCK position.
•  Inspect for continuity between VSS terminal A (wiring harness-side) and ground.
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 11.
6
INSPECT VSS GROUND CIRCUIT FOR OPEN CIRCUIT
•  Verify that the VSS connector is disconnected.
•  Inspect for continuity between VSS (wiring harness-side) terminal C and ground.
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 11.
7
INSPECT PCM CONNECTOR FOR POOR CONNECTION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is the connection normal?
Yes
Go to the next step.
No
Repair or replace the pin or connector, then go to Step 11.
8
INSPECT VEHICLE SPEED SIGNAL CIRCUIT FOR OPEN CIRCUIT
•  Disconnect the PCM connector and VSS connector.
•  Inspect for continuity between VSS terminal B and PCM terminal 1AX (ZY)/1J (LF).
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 11.
9
INSPECT VEHICLE SPEED SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Verity that the VSS connector and PCM connector are disconnected.
•  Inspect for continuity between PCM terminal 1AX (ZY)/1J (LF) and body ground.
•  Is there continuity?
Yes
Repair or replace the wiring harness, then go to the next step.
No
Replace the VSS, then go to the next step.
(See VEHICLE SPEED SENSOR (VSS) REMOVAL/INSTALLATION[FN4A-EL].)
10
INSPECT VEHICLE SPEED SENSOR
•  Inspect the VSS.
•  Is VSS normal?
Yes
Go to the next step.
No
Repair or replace the VSS, then go to Step 11.
11
VERIFY TROUBLESHOOTING OF DTC P0720 COMPLETED
•  Make sure to reconnect all the disconnected connectors.
•  Clear the DTC from the memory using the M-MDS.
•  Drive the vehicle under the following conditions for 4.5 s or more while monitoring PIDs.
―  Engine coolant temp (ECT PID): 60 °C {140 °F} or more
―  Drive in D or M range
―  Frequency of input/turbine speed sensor: 800 Hz or more
•  Is the PENDING CODE present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION[ZJ, ZY, Z6].)
(See PCM REMOVAL/INSTALLATION[LF, L3].)
No
No concern is detected. Go to the next step.
12
VERIFY AFTER REPAIR PROCEDURE
•  Perform the "After Repair Procedure".
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE[FN4A-EL].)
No
DTC troubleshooting completed.


Z6

DTC P0720

Vehicle speed sensor (VSS) circuit malfunction
DETECTION CONDITION
•  Vehicle speed signal is not input after the following conditions are met and 4.5 s or more have passed.
―  D range switch ON
―  Engine coolant temperature 60 °C {140 °F} or more
―  Turbine speed 1,500 rpm or more
Diagnostic support note:
•  This is a continuous monitor (CCM).
•  The MIL illuminates if the PCM detects the above malfunction conditions during the first drive cycle.
•  The PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
•  FREEZE FRAME DATA is available.
•  The AT warning light illuminates.
•  The DTC is stored in the PCM memory.
POSSIBLE CAUSE
•  VSS malfunction
•  Open circuit in wiring harness between VSS terminal B and PCM terminal 1AY
•  Short to ground in wiring harness between VSS terminal B and PCM terminal 1AY
•  Open circuit in wiring harness between VSS terminal A and PCM terminal 1BC
•  Short to ground in wiring harness between VSS terminal A and PCM terminal 1BC
•  Open circuit in wiring harness between VSS terminal C and body ground
•  Damaged connectors between VSS and PCM
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA HAS BEEN RECORDED
•  Has the FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
3
INSPECT VSS CONNECTOR FOR POOR CONNECTION
•  Turn the ignition switch to the LOCK position.
•  Disconnect the VSS connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is the connection normal?
Yes
Go to the next step.
No
Repair or replace the pin or connector, then go to Step 11.
4
INSPECT VSS POWER CIRCUIT FOR OPEN CIRCUIT
•  Verify that the VSS connector is disconnected.
•  Turn the ignition switch to the ON position (engine off).
•  Inspect the voltage between VSS terminal A (wiring harness-side) and ground.
•  Is the voltage B+?
Yes
Go to Step 6.
No
Go to the next step.
5
INSPECT VSS POWER CIRCUIT FOR SHORT TO GROUND
•  Turn the ignition switch to the LOCK position.
•  Inspect for continuity between VSS terminal A (wiring harness-side) and ground.
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 11.
6
INSPECT VSS GROUND CIRCUIT FOR OPEN CIRCUIT
•  Verify that the VSS connector is disconnected.
•  Inspect for continuity between VSS (wiring harness-side) terminal C and ground.
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 11.
7
INSPECT PCM CONNECTOR FOR POOR CONNECTION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is the connection normal?
Yes
Go to the next step.
No
Repair or replace the pin or connector, then go to Step 11.
8
INSPECT VEHICLE SPEED SIGNAL CIRCUIT FOR OPEN CIRCUIT
•  Disconnect the PCM connector and VSS connector.
•  Inspect for continuity between VSS terminal B and PCM terminal 1AY.
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 11.
9
INSPECT VEHICLE SPEED SIGNAL CIRCUIT FOR SHORT TO GROUND
•  Verity that the VSS connector and PCM connector are disconnected.
•  Inspect for continuity between PCM terminal 1AY and body ground.
•  Is there continuity?
Yes
Repair or replace the wiring harness, then go to the next step.
No
Replace the VSS, then go to the next step.
(See VEHICLE SPEED SENSOR (VSS) REMOVAL/INSTALLATION[FN4A-EL].)
10
INSPECT VEHICLE SPEED SENSOR
•  Inspect the VSS.
•  Is VSS normal?
Yes
Go to the next step.
No
Repair or replace the VSS, then go to Step 11.
11
VERIFY TROUBLESHOOTING OF DTC P0720 COMPLETED
•  Make sure to reconnect all the disconnected connectors.
•  Clear the DTC from the memory using the M-MDS.
•  Drive the vehicle under the following conditions for 4.5 s or more while monitoring PIDs.
―  Engine coolant temp (ECT PID): 60 °C {140 °F} or more
―  Drive in D or M range
―  Frequency of input/turbine speed sensor: 800 Hz or more
•  Is the PENDING CODE present?
Yes
Replace the PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION[ZJ, ZY, Z6].)
No
No concern is detected. Go to the next step.
12
VERIFY AFTER REPAIR PROCEDURE
•  Perform the "After Repair Procedure".
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE[FN4A-EL].)
No
DTC troubleshooting completed.