Circuit Description
WARNING: This page is about a different car, the 2003 Buick Regal and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
The 1-2 shift solenoid valve controls transmission fluid pressure acting on the 1-2 shift valves to position the valves for the appropriate gear. The 1-2 shift solenoid valve is a normally-open exhaust valve located on the control valve body. A fused circuit supplies ignition voltage to the 1-2 shift solenoid valve. The PCM commands the solenoid ON or OFF by switching the ground path. When the 1-2 shift solenoid valve is commanded ON, the PCM senses low voltage. When the 1-2 shift solenoid valve is commanded OFF, the PCM senses high voltage.
If the PCM detects a continuous open, short to ground or short to power in the 1-2 shift solenoid valve circuit, then DTC P0753 sets. DTC P0753 is a type "B" DTC.