P1775 (37) - Solenoid Switch Valve Latched In TCC Position

Name of Code:
P1775 (37) - Solenoid Switch Valve Latched in TCC Position

When Monitored:
During an attempted shift into 1st gear.

Set Condition:
This code is set if three unsuccessful attempts are made to get into 1st gear in one given key start.

Theory of Operation:
The solenoid switch valve (SSV) controls the direction of the transmission fluid when the L-R solenoid is energized. The SSV will be in the downshifted position in 1st gear, thus directing the fluid to the L-R clutch circuit. In 2nd, 3rd, and 4th, it will be in the upshifted position and directs the fluid into the torque converter clutch (TCC).

When shifting into 1st gear, a special hydraulic sequence is performed to ensure SSV movement into the downshifted position. The L-R pressure switch is monitored to confirm SSV movement. If movement is not confirmed (the L-R pressure switch does not close), 2nd gear is substituted for 1st.

Transmission Effects:
Transmission will have no 1st gear (2nd gear will be substituted), and no EMCC operation. The MIL will illuminate after 5 minutes of substituted gear operation.

Possible Causes:
- PRNDL indicates a valid OD code in the hydraulic reverse position
- Valve body - Solenoid Switch Valve stuck in TCC position
- High idle speed
- Solenoid malfunction - may also set code P1784 (81)
- L-R Pressure Switch Sense circuit shorted to battery