OSCGEAR in DRIVE MODE

WARNING: This page is about a different car, the 2006 Mercury Grand Marquis and 2006 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.

The OSC function is used to test the transmission gear changes. The advantage of using OSC for changing gears is to allow the technician to easily test a specific gear and/or upshift or downshift that has been identified as the customer complaint. When using OSC to command a shift change, the PCM should command the correct or normal pressure for that shift. The transmission will remain in the gear that OSC has commanded until OSC commands another gear or OSC is cancelled.

The OSC functions for the OSCGEAR parameter allow the technician to choose the following options:

1 - Directs PCM to command 1st gear
2 - Directs PCM to command 2nd gear
3 - Directs PCM to command 3rd gear
4 - Directs PCM to command 4th gear
XXX - Cancels OSC command for GEAR (returns to normal operation)

The vehicle requirements must be met when sending the OSC value for GEAR. If the vehicle requirements are not met when sending the OSC value, an error message will appear. When the error message is received, OSC is aborted and must be restarted. After the OSC value for GEAR is sent, if the vehicle requirements are no longer met, the error message will not appear but the OSC value will be cancelled by the PCM (monitor corresponding PID). The OSC value XXX may be sent anytime to cancel OSC.

It is recommended to use the OSCTCC parameter in OSC to first turn OFF the converter clutch when testing the transmission gear changes. This will allow the technician to evaluate just the gear changes. If the torque converter clutch is not turned off, then the PCM may command the torque converter clutch to lock during a shift. This could make it more difficult for the technician to determine whether a bad shift is the result of the torque converter engaging or the actual gear change.

The vehicle requirements for sending a OSCGEAR value is as follows:

Engine is running
Gear selector is in OVERDRIVE
Vehicle speed is greater than 3 km/h (2 mph)
Vehicle speed must be lower than 48 km/h (30 mph) to command a downshift to 1st gear
Vehicle speed must be lower than 97 km/h (60 mph) to command a downshift to 2nd gear
Vehicle speed must be lower than 145 km/h (90 mph) to command a downshift to 3rd gear
Vehicle speed must be greater than 48 km/h (30 mph) to command an upshift to 4th gear