P0787 GMC Shift/Timing Solenoid Low

Possible causes

– Low transmission fluid level
– Dirty transmission fluid
– Faulty shifting solenoid valve
– Shifting solenoid valve harness is open or shorted
– Shifting solenoid valve circuit poor electrical connection

What about the obd code?

Code P0787 GMC is detected when the Engine Control Module (ECM) detects short in solenoid valve ST circuit 4 times when solenoid valve ST is operated

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)

P0787 GMC Description

Shift solenoid valve ST is switched ON OFF by a signal from Engine Control Module (ECM) so that let in or out timing of 2nd brake is adjusted by operating orifice control valve. Therefore, shift solenoid valve ST operates when letting in or out reverse clutch.