P0750: OBD-II code P0750 flags an electrical fault at shift solenoid A — the TCM can't reliably switch the solenoid to command a gear change.

Symptoms

• Check engine light is on; the transmission may not shift into certain gears or shift harshly.
• The vehicle may enter limp mode stuck in a single gear (typically 3rd or 4th) as a protective measure.
• Harsh or delayed engagement into drive or specific gears when the solenoid fails to actuate.

Common causes

• A failed shift solenoid A with an open or shorted internal coil.
• Damaged wiring or a corroded connector at the transmission solenoid pack.
• A failed TCM solenoid driver circuit — less common but possible.

What to do?

Command shift solenoid A on and off with a scan tool. Measure the solenoid's coil resistance (usually 20-40 Ω). Test the wiring between the TCM and the solenoid. Replace the solenoid pack if the coil is out of spec.