DTC P0720

BHE050201026W13

DTC P0720

Vehicle speed sensor (VSS) malfunction (open circuit/short to ground)

DETECTION CONDITION

• While driving in D range at turbine speed of 2,000 rpm or more (25.5 s or more after shifting to D range), vehicle speed signal is 5 km/h {3 mph} or less for 3.5 s or more.

Diagnostic support note:

• This is a continuous monitor (CCM).
• MIL illuminates if TCM detects the above malfunction condition during the first drive cycle.
• PENDING CODE is not available.
• FREEZE FRAME DATA is available.
• AT warning light illuminates.
• DTC is stored in TCM memory.

POSSIBLE CAUSE

• VSS malfunction
• Short to ground in wiring harness between VSS terminal A and TCM terminal 2K
• Open circuit in wiring harness between VSS terminal A and TCM terminal 2K
• Open circuit in wiring harness between VSS terminal B and ignition switch (IG1)
• Open circuit in wiring harness between VSS terminal C and body ground
• Damaged connectors between VSS and TCM
• TCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1

VERIFY FREEZE FRAME DATA HAS BEEN RECORDED

• Has 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 REPAIR INFORMATION AVAILABILITY

• Verify related Service Bulletins and/or on-line repair information availability.
• Is any related repair information available?
Yes
Perform repair or diagnosis according to the available repair 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).
• Are the connector and terminals normal?
Yes
Go to the next step.
No
Repair or replace the connector and/or terminal, then go to Step 10.
4

INSPECT VSS POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT

• Turn the ignition switch to the ON position (engine off).
• Inspect the voltage at VSS connector terminal B.
• Is the terminal voltage B+?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 10.
5

INSPECT VSS GROUND CIRCUIT FOR OPEN CIRCUIT

• Turn the ignition switch to the LOCK position.
• Inspect for continuity between the VSS (wiring harness-side) terminal C and body ground.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 10.
6

INSPECT TCM CONNECTOR FOR POOR CONNECTION

• Disconnect the TCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Are the connector and terminals normal?
Yes
Go to the next step.
No
Repair or replace the connector and/or terminal, then go to Step 10.
7

INSPECT VSS SIGNAL CIRCUIT FOR OPEN CIRCUIT

• Inspect for continuity between the VSS (wiring harness-side) terminal A and TCM (wiring harness-side) terminal 2K.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 10.
8

INSPECT VSS SIGNAL CIRCUIT FOR SHORT TO GROUND

• Inspect for continuity between the VSS (wiring harness-side) terminal A and body ground.
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 10.
9

INSPECT VSS

• Inspect the VSS.
• Is the VSS normal?
Yes
Go to the next step.
No
Replace the VSS, then go to the next step.
10

VERIFY TROUBLESHOOTING OF DTC P0720 COMPLETED

• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the TCM memory using the WDS or equivalent.
• Drive the vehicle with vehicle speed of 5 km/h {3 mph} or less and turbine speed of 2,000 rpm or more for 3.5 s or more
• Is the same DTC present?
Yes
Replace the TCM, then go to the next step.
No
Go to the next step.
11

VERIFY AFTER REPAIR PROCEDURE

• Perform the "After Repair Procedure".
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.