Drive Test - Pressure Added for Engagements and Upshifts
The OSC values for HRSH_SHFT to command a slight or moderate increase in hydraulic pressure to test for firmer engagements and upshifts are as follows:
- 0 or OFF - PCM in normal pressure control for shifts and engagements and OSC is cancelled
- 1 or ON - Commands PCM to moderately increase hydraulic pressure during engagements and upshifts
Setting HRSH_SFT to 1 or ON allows the technician to moderately increase the pressure when performing engagements such as P-R, P-D, N-R, N-D, R-D and when performing automatic upshifts. This can provide additional diagnostic information to help the technician determine whether the electronic pressure control system is providing at least limited control (a normal shift would become firmer). Using OSC to control HRSH_SHFT to [1 or ON] should make a softer engagement or shift more normal and an already normal shift or engagement firmer by slightly increasing the pressure. This test should only be used to provide additional diagnostic information and should not be the only scan tool or test to determine a faulty electronic or hydraulic component.