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2-3 Shift Solenoid Valve

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The 2-3 shift solenoid valve is a normally open exhaust valve that is attached to the valve body. The PCM controls the solenoid by grounding the solenoid through an internal quad driver. The 2-3 shift solenoid valve is on in 3rd and 4th gear. When commanded on, the 2-3 shift solenoid valve redirects fluid to act on the 2-3 shift valve. See SHIFT SOLENOID VALVE STATE & GEAR RATIO  table.

There are 2 PCM related DTCs associated with the 2-3 shift solenoid valve: P0756 and P0758.

The PCM monitors the 2-3 shift solenoid circuit for an open or short to ground condition. If the PCM detects an open or short to ground condition, then DTC P0758 sets. If the PCM detects an incorrect gear ratio, then DTC P0756 sets. When DTC P0758 or P0756 sets, the PCM commands maximum line pressure, freezes shift adapts from being updated, and inhibits 3-2 downshifts.

SHIFT SOLENOID VALVE STATE & GEAR RATIO

Gear 1-2 Shift Solenoid 2-3 Shift Solenoid Gear Ratio
1st On Off 2.48:1
2nd Off Off 1.48:1
3rd Off On 1.00:1
4th On On .75:1
Reverse On Off 2.08:1