Pinpoint Test E : OSS (Output Shaft Speed) Sensor: Notes
Refer to Transmission Controls - TorqShift 6 for schematic and connector information.
Normal Operation
The OSS sensor is a Hall-effect type sensor that provides a signal to the PCM that changes in frequency as the rotating speed of the output shaft ring gear varies. The PCM also compares the OSS sensor signal with the TSS sensor signal to determine the gear ratio provided by the rear planetary gearset. The PCM uses the OSS sensor signal as an input for its strategies for shifts and TCC operation. The PCM also uses the OSS sensor signal for transmission fault detection and diagnostics. DTC s are set. When the DTC P0720 is set, the module goes into failsafe mode cutting off the voltage to the transmission solenoids which revert to full line pressure, with the following gears only available, P, R, N, and 5M.
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| P0720 | Output Shaft Speed Sensor Circuit | DTC P0720 sets when vehicle conditions (mainly turbine speed) indicate that OSS output should be present. Electrical failures of the OSS wiring or a failure of the sensor itself can cause this failure. Hydraulic/mechanical failure of the transmission that results in no vehicle movement in Reverse or 1st gear may also cause DTC P0720 to set. Verify the transmission operation before starting this pinpoint test. |
| P0721 | Output Shaft Speed Sensor Circuit Range/Performance | Unrealistic change in the OSS sensor signal, erratic or intermittently no output. |
| P0722 | Output Shaft Speed Sensor Circuit No Signal | No input from the OSS sensor. |
- Wiring, terminals or connectors
- OSS sensor
- PCM
- Excessive transmission slippage (No vehicle movement in 1st or Reverse)