AF23-5 Automatic Transaxle
AF23-5 AUTOMATIC TRANSAXLEDTC P0722
Test 1-3:
Test 4-10:
Circuit Description with AF23-5 Automatic Transaxle
The output shaft speed (OSS) sensor assembly provides vehicle speed information to the transmission control module (TCM). The OSS sensor assembly is a hall-effect sensor. The sensor is mounted in the transmission case facing the parking lock gear which is splined to the output shaft assembly. As the output shaft and parking lock gear rotate, the toothed parking lock gear produces a square wave voltage signal as the teeth pass through the magnetic field of the sensor. The number of pulses increases 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 A DTC.
Conditions for Running the DTC
Fail Case 1
^ No TR Switch DTC P0705.
^ No TFT DTCs P0711, P0712, or P0713.
^ No ISS DTC P0717.
^ The ignition voltage is 10.5-18 volts.
^ Vehicle speed is 66 km/h (41 mph).
^ Trans. Protection Mode is OFF.
^ The calculated transmission output shaft speed (OSS) is 300 RPM or greater.
^ The transmission is not shifting.
^ If the transmission temperature is greater than 20°C (68°F), the TR Switch has been DRIVE for 2.5 seconds or greater.
^ If the transmission temperature is 0-20°C (32-68°F), the TR Switch has been DRIVE for 10 seconds or greater.
^ It the transmission temperature is less than 0°C (32°F), the TR Switch has been DRIVE for 3 minutes or greater.
Fail Case 2
^ The ignition voltage is 10.5-18 volts.
^ Trans. Protection Mode is OFF.
^ The engine is running.
Conditions for Setting the DTC
Fail Case 1
The TCM does not detect any pulses from the OSS and there are 6,000 pulses from the ISS.
Fail Case 2
The OSS signal circuit is open or shorted for 30 seconds or greater.
Action Taken When the DTC Sets
^ The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL).
^ The TCM turns the Trans. Protection Mode ON. When the Trans. Protection Mode is ON, the following conditions occur:
- The transmission will operate in 5th gear when the transmission is shifted into D or I range and 2nd gear when shifted into L range.
- The line pressure is at maximum.
- The torque converter clutch (TCC) is disabled.
- The TCM freezes the transmission adaptive functions.
^ The TCM calculates the output speed based on the input speed.
^ The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as Freeze Frame and Failure Records.
^ The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as a Failure Record.
^ The TCM stores DTC P0722 in TCM history,
Conditions for Clearing the MIL/DTC
^ The ECM turns OFF the MIL after the third consecutive drive trip in which the TCM does not send a MIL illumination request.
^ A scan tool can clear the MIL/DTC.
^ The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission -related diagnostic fault occurring.
^ The TCM cancels the DTC default actions when the ignition is OFF long enough in order to power down the TCM.
Diagnostic Aids
Ensure the OSS sensor is properly torqued to the transmission housing.