System Description

WARNING: This page is about a different car, the 2011 Toyota Matrix. However, it is still accessible from the selected car via links, so may be relevant.

The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd or 4th (O/D) gear).

Then the ECM compares the actual gear with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves, valve body or automatic transaxle (clutch, brake or gear etc.).

Fig 1: Identifying Pressure Control Solenoid With Graph

DTC No.	DTC Detection Condition	Trouble Area
P0776	The gear required by the ECM does not match the actual gear when driving (2-trip detection logic)	Shift solenoid valve SL2 remains open or closed Valve body is blocked Automatic transaxle (clutch, brake or gear etc.)