Using Output State Control (OSC) and Accessing PIDs
To confirm that the output state control (OSC) value was sent by the scan tool and the PCM has accepted the OSC substitution, a corresponding PID or PIDs for each OSC parameter should be monitored. Additional PIDs should be monitored to help the technician adequately diagnose the transaxle.
The following is a list of OSC parameters and their corresponding PIDs:
| OSC Parameter | Corresponding PID | PID Description |
|---|---|---|
| SSA | SSA | Shift Solenoid A Commanded ON/OFF |
| SSB | SSB | Shift Solenoid B Commanded ON/OFF |
| EPC | EPC | Pressure Control A Commanded Pressure (psi) |
| SSC | SSC | Shift Solenoid C Commanded Duty Cycle (%) |
| SSD | SSD | Shift Solenoid D Commanded Duty Cycle (%) |
| SSE | SSE | Shift Solenoid E Commanded Duty Cycle (%) |
| GEAR | GEAR | Commanded Trans Gear (Use In DRIVE) |
| GEAR | OSCGEAR | Gear Commanded Control Status Requested By OSC: PCM = Scheduled by PCM, OSC not in control 1 = 1st gear commanded by OSC 2 = 2nd gear commanded by OSC 3 = 3rd gear commanded by OSC 4 = 4th gear commanded by OSC |
| TCC | TCC | Torque Converter Commanded Duty Cycle |
| TCC | OSCTCC | Torque Converter Control Status Requested By OSC: PCM = Scheduled by PCM, OSC not in control OFF = TCC commanded OFF by OSC ON = TCC commanded ON by OSC |
| FIRM_SFT | FIRMSFT | Firm Shift Control Status Requested By OSC: OFF = FIRM SHIFT MODE not commanded by OSC ON = FIRM SHIFT MODE commanded by OSC |
To confirm that the OSC substitution occurred, command the OSC value and monitor the corresponding PID value. If the value of the corresponding PID is the same as the value sent from OSC, then the OSC substitution was successful.
The following general PID list may be of use to the technician when exercising OSC:
| PIDs | PID DESCRIPTION |
|---|---|
| BPP | Brake Pedal Position (BPP)/Brake Switch ON/OFF |
| GEARTOP | Highest Gear Permitted |
| RPM | Engine Revolutions Per Minute |
| TR | Transmission Range Sensor (Present Position) |
| TCCRAT | Torque Converter Speed Ratio (RPM/TSS) |
| TR_1 | Digital Transmission Range Sensor TR1, 1 = switch open 0 = switch closed |
| TR_2 | Digital Transmission Range Sensor TR2, 1 = switch open 0 = switch closed |
| TR_3 | Digital Transmission Range Sensor TR3, 1 = switch open 0 = switch closed |
| TR_4 | Digital Transmission Range Sensor TR4, 1 = switch open 0 = switch closed |
| TFT | Transmission Fluid Temperature (°F) |
| VSS | Vehicle Speed (MPH) |