Code No.P0720: Output shaft speed sensor system


PROBABLE CAUSES


OPERATION


The output shaft speed sensor detects the speed of parking gear, and sends the pulse signal to A/T-ECU.

DIAGNOSIS CODE SET CONDITIONS


While the engine is running, if any output shaft speed sensor pulse signal is not detected even when the input shaft speed sensor pulse signal is detected (1 drive cycle), code No.P0720 is set.
note Trouble judgement monitoring starts when specified time has passed after engine starting and garage shifting (P/R/N → D).
As the ATF temperature becomes lower, the specified time before the monitoring start gets longer. (ATF temperature 20°C: 2.5 seconds, 0°C: 20 seconds, maximum 60 seconds)

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list
Item 5: Output shaft speed sensor (Refer to data list reference table ).

Q. Is the check result normal?
Go to Step 6.
Go to Step 2.

STEP 2. Measure the resistance at output shaft speed sensor connector.
Disconnect the connector, and measure the resistance between terminal PGB+ line and PBG- line at the sensor side.
OK: 560 - 680 Ω (at 20°C)

Q. Is the check result normal?
Go to Step 3.
Go to Step 10.

STEP 3. Measure the resistance at output shaft speed sensor connector.
Disconnect the connector, and measure the resistance between terminal PGB- line and earth at the wiring harness side.
OK: 2 Ω or less

Q. Is the check result normal?
Go to Step 7.
Go to Step 4.

STEP 4. Check for open circuit in PGB- line between output shaft speed sensor connector and A/T-ECU connector.

Q. Is the check result normal?
Go to Step 5.
Repair the connector(s) or wiring harness.

STEP 5. Shielded wire check
Check the shielded wire for any damage.

Q. Is the check result normal?
Go to Step 6.
Repair the wiring harness.

STEP 6. Check whether the diagnosis code is set again.
Check again if the diagnosis code is set.

Q. Is diagnosis code No.P0720 set?
Replace the A/T-ECU.
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction).

STEP 7. Measure the voltage at output shaft speed sensor connector.
(1)Disconnect the connector, and measure the voltage between terminal PGB+ line and earth at the wiring harness side.
(2)Turn the ignition switch to the ON position.
OK: 4.5 - 5.1 V

Q. Is the check result normal?
Go to Step 11.
Go to Step 8.

STEP 8. Check for open circuit and short circuit in PGB+ line between output shaft speed sensor connector and A/T-ECU connector.

Q. Is the check result normal?
Go to Step 9.
Repair the connector(s) or wiring harness.

STEP 9. Shielded wire check
Check the shielded wire for any damage.

Q. Is the check result normal?
Go to Step 6.
Repair the wiring harness.

STEP 10. Check the input shaft speed sensor
Remove the output shaft speed sensor. Remove deposits such as foreign material or metal chip from the sensor tip, and check the sensor for damage and any faults.

Q. Is the check result normal?
Go to Step 6.
Replace the output shaft speed sensor.

STEP 11. Parking gear inspection
Visually check the parking gear for damage.

Q. Is the check result normal?
Eliminate the cause of the noise.
Replace the parking gear.