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For 1990-2009 cars only
Makes 🢒 Holden 🢒 2005 🢒 Commodore Berlina 🢒 DTC 🢒 DTC P0722

DTC P0722 V6

DTC Description

This diagnostic procedure supports DTC P0722 Vehicle Speed Sensor Circuit Low Voltage.

Circuit Description

The vehicle speed sensor (VSS) provides vehicle speed information to the transmission control module (TCM). The VSS is a permanent magnet generator. The sensor is mounted in the extension housing facing the rear internal gear which is splines to the output shaft assembly. As the output shaft and internal gear rotate, the toothed rotor of the internal gear produces AC voltage as the rotor teeth pass through the magnetic field of the sensor. The AC voltage level and the number of pulses increase as the speed of the vehicle increases. The TCM converts the voltage to vehicle speed. The TCM uses the output shaft speed signal to determine shift timing and torque converter clutch (TCC) scheduling.

If the TCM detects no vehicle speed when there is engine speed in a drive gear range, then DTC P0722 sets. DTC P0722 is a type B DTC.

Refer to Automatic Transmission Controls Schematics , Automatic Transmission Inline 20-Way Connector End View, Automatic Transmission Internal Connector End Views , Automatic Transmission Control Module Connector End Views , and Automatic Transmission Related Connector End Views to aid in diagnosis.

Conditions for Running the DTC
    • No DTCs P0723, P1810, P1815 or P1816.
    • Ignition voltage is 8-18 V.
    • TFT is -40 to +150°C.
    • The engine run time is greater than 5 seconds.
    • The throttle position is greater than 12 percent.
    • The engine torque is 108-882 N·m.

Conditions for Setting the DTC

The transmission output shaft speed is less than 50 RPM for 3 seconds.

Action Taken When the DTC Sets
    • The TCM illuminates the check powertrain icon during the second consecutive trip in which the Conditions for Setting the DTC are met.
    • The TCM commands maximum line pressure.
    • The TCM freezes transmission adaptive functions.
    • The TCM calculates vehicle speed from the automatic transmission engine RPM. and commanded gear.
    • At the time of the first failure, the TCM records the operating conditions when the conditions for setting the DTC are met. The TCM stores this information as a Failure Record.
    • At the time of the second failure, the ECM records the operating conditions when the conditions for setting the DTC are met. The ECM stores this information as a Freeze Frame.
    • The TCM stores DTC P0722 in TCM history.

Conditions for Clearing the DTC
    • The ECM turns off the check powertrain icon after the sixth consecutive drive trip in which the TCM does not send a check powertrain icon illumination request.
    • Tech 2 can clear the DTC.
    • The TCM clears the DTC from TCM history is the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring.
    • The TCM cancels the default actions when the ignition is off long enough in order to power down the TCM.

Diagnostic Aids
    • Inspect the rear internal gear teeth for damage.
    • Visually inspect the VSS for cracks or damage.
    • Ensure the VSS is properly torqued to the extension housing.

Test Description

The following numbers refer to the step numbers in the diagnostic table:

2 Disable the traction control system when performing this step. When the ignition key is cycled off and then cycled back on, the traction control system defaults to on.

3 Checks the VSS for correct resistance.

4 Checks if the VSS and associated circuits are shorted to ground.

5 Checks the VSS produces an AC voltage when the output shaft is rotated.

6 Checks the integrity of the circuits between the TCM and the VSS.

Step

Action

Yes

No

1

Has the Diagnostic System Check been performed?

Go to Step 2

Refer to Diagnostic System Check - Automatic Transmission

2
  1. Connect Tech 2 to the DLC.
  2. Turn on the ignition, with the engine off.

    3. Important: Before clearing the DTC, use the Tech 2 Freeze Frame/Failure Record in order to record the transmission parameters at the time the DTC set. Using Tech 2 to clear the DTC(s) erases the Freeze Frame/Failure records from the TCM.

  3. On Tech 2 select: Transmission/Automatic Transmission/Diagnostic Trouble Codes/Freeze Frame.
  4. Select the relevant DTC and note the parameters at the time of the DTC setting.
  5. On Tech 2 select: Diagnostic Trouble Codes/Clear Engine and Transmission DTCs.
  6. Follow the instructions on Tech 2 and clear the DTCs.
  7. Raise and support the rear axle assembly, refer to Section 0A General Information.
  8. Start the engine.
  9. Disable the traction control system.
  10. Place the transmission in any drive range.
  11. On Tech 2 select: Data Display/Transmission Data.

With the drive wheels rotating, does the Tech 2 AT Output Speed parameter increase with the drive wheel speed?

Check for an intermittent fault in the circuit, refer to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3
  1. Turn off the ignition.
  2. Disconnect connector B83-X1 from the sensor.
  3. Using a multimeter set to measure resistance, probe across the speed sensor pins A and B.

Does the multimeter display 976-2354 Ω?

Go to Step 4

Go to Step 6

4
  1. Using a multimeter set to measure resistance, probe between connector B83-X1 pin A and a known ground.
  2. Using a multimeter set to measure resistance, probe between connector B83-X1 pin B and a known ground.

Does the multimeter display greater than 50 kΩ in both instances?

Go to Step 5

Go to Step 6

5
  1. Place the transmission in neutral.
  2. Using a multimeter set to measure AC voltage, probe across the speed sensor pins A and B.
  3. Rotate a rear wheel by hand.

Does the multimeter display 0.3 V AC?

Go to Step 6

Go to Step 7

6
  1. Disconnect connector A112-X1 from the TCM.
  2. Test circuits 400 and 401 for the following conditions:
    3. • Short to ground
    • Open circuit
    • Short together

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the vehicle speed sensor, refer to Vehicle Speed Sensor Replacement.

Did you complete the replacement?

Go to Step 9

--

8

Replace the TCM, refer to Transmission Control Module Replacement.

Did you complete the replacement?

Go to Step 9

--

9

Perform the following procedure in order to verify the repair:

  1. On Tech 2 select: Diagnostic Trouble Codes/Clear Engine and Transmission DTCs.
  2. Follow the instructions on Tech 2 and clear any DTCs.
  3. Operate the vehicle so the transmission output speed is greater than 500 RPM for 3 seconds.
  4. On Tech 2 select: Diagnostic Trouble Codes/Read DTC Information.

Has DTC P0722 set?

Go to Step 2

Go to Step 9

10

On Tech 2 select: Diagnostic Trouble Codes/Read DTC Information.

Does Tech 2 display any DTCs you have not diagnosed?

Refer to Diagnostic Trouble Code (DTC) List/Type

System OK

When all diagnosis and repairs are completed, check the system for correct operation.