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

Name of code: $37 (P1775) - Solenoid Switch 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/TCC solenoid is energized. 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 valve stuck in TCC position
- High idle speed
- Solenoid malfunction - L-R pressure switch will not close
- L-R Pressure Switch Sense circuit shorted to battery