Code No.23: Output Shaft Speed Sensor System
OPERATION
The output shaft speed sensor detects the speed of the transfer drive gear and sends the information to the engine-A/T-ECU as a pulse signal.DIAGNOSIS CODE SET CONDITIONS
If the output pulse from the output shaft speed sensor has been lost for one second or more while the vehicle is being driven, it is judged that there is an open circuit or short circuit in the output shaft speed sensor, and diagnosis code 23 is set.If the code No.23 is set four times, the transmission will be fixed in 3rd gear as a fail-safe measure. However, the transmission can be downshifted to 2nd gear by operating the selector lever.
PROBABLE CAUSES
- Malfunction of output shaft speed sensor
- Malfunction of transfer drive gear or driven gear
- Damaged harness wires and connectors
- Malfunction of the engine-A/T-ECU
DIAGNOSIS PROCEDURE
STEP 1. MUT-II/III data list
) <Except for Hong Kong spec.>.Item 02: Input shaft speed sensor (Refer to data list reference table
) <Vehicles for Hong Kong spec.>.Q: Is the check result normal?
YES:
Intermittent malfunction (Refer to GROUP 00 -
How to Cope with Intermittent Malfunction ).NO: Go to Step 2
.STEP 4. Measure the voltage at engine-A/T-ECU connector C-136.
- Connect output shaft speed sensor connector B-20.
- Turn the ignition switch to the ON position.
- Measure the voltage between engine-A/T-ECU connector C-136 terminal No.88 and earth.
OK: 0.5 V or less
Q: Is the check result normal?
YES:
Go to Step 7.NO: Go to Step 5
.STEP 6. MUT-II/III data list
) <Except for Hong Kong spec.>.Item 02: Input shaft speed sensor (Refer to data list reference table
) <Vehicles for Hong Kong spec.>.Q: Is the check result normal?
YES:
Intermittent malfunction (Refer to GROUP 00 -
How to Cope with Intermittent Malfunction ).NO: Replace the engine-A/T-ECU.
STEP 9. Measure the voltage at output shaft speed sensor connector B-20.
- Disconnect the connector, and measure the voltage between terminal 3 and earth at the wiring harness side.
- Turn the ignition switch to the ON position.
OK: System voltage
Q: Is the check result normal?
YES:
Go to Step 12.NO: Go to Step 10
.STEP 12. Measure the voltage at output shaft speed sensor connector B-20.
- Disconnect the connector, and measure the voltage between terminal 2 and earth at the wiring harness side.
- Turn the ignition switch to the ON position.
OK: 4.5 -
4.9 V
Q: Is the check result normal?
YES:
Go to Step 18.NO: Go to Step 13
.STEP 13. Measure the voltage at engine-A/T-ECU connector C-136.
- Disconnect output shaft speed sensor connector B-20.
- Turn the ignition switch to the ON position.
- Measure the voltage between engine-A/T-ECU connector C-136 terminal No.73 and earth.
OK: 4.5 -
4.9 V
Q: Is the check result normal?
YES:
Go to Step 16.NO: Go to Step 14
.STEP 18. Measure the output wave pattern of the output shaft speed sensor at engine-A/T-ECU connector C-136 (using an oscilloscope).
- Shift the selector lever to the D range.
- Accelerate the vehicle to approximately 50 km/h (shift range; 3rd).
- Connect an oscilloscope, and measure the voltage between engine-A/T-ECU connector C-109 terminal No.104 and earth.
OK: A wave pattern such as the one shown on (Check Procedure Using an Oscilloscope) should be output, and the maximum value should be 4.8 V or more and the minimum value should be 0.8 V or less. There should be no noise in the output wave pattern.
(Check Procedure Using an Oscilloscope) should be output, and the maximum value should be 4.8 V or more and the minimum value should be 0.8 V or less. There should be no noise in the output wave pattern.Q: Is the check result normal?
YES:
Go to Step 6.NO: Go to Step 19
.