DTC Advanced Diagnostics: P0731: General Description

Courtesy of HONDA, U.S.A., INC.

Two-way clutch position required to shift in each shift position/mode 

*: Possible to shift regardless of the two-way clutch position

The two-way clutch switches forward and reverse by switching to one-way clutch function that idles one side and lock function that disables idle both sides. The two-way clutch switches forward and reverse by driving two-way clutch actuator valve with shift solenoid valves A, B, and D, and clutch pressure control solenoid valve B. The two-way clutch switching position is monitored by the two-way clutch actuator valve stroke sensor which measures the stroke position of the two-way clutch actuator valve. The two-way clutch position that is required to shift in each shift position/mode is shown in the table. The detection is performed to guarantee the vehicle start in case the gear changes to neutral that is expected to be 1st gear due to the malfunction of one-way clutch function. If the value difference between the mainshaft speed sensor and the countershaft speed sensor is a specified value when steady driving at 1st gear and actual torque converter slip rate is in a specified range and the value of transmission fluid pressure sensor F is a specified value for a specified time, the transmission control module (TCM) determines the condition as neutral when it is expected to be 1st gear and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type