DT Codes . com
DTC - Diagnostic Trouble Codes information

P0757

Powertrain Codes

P0757 - GMC - 2-3 Shift Solenoid Stuck On

Symptoms

- Engine Light ON (or Service Engine Soon Warning Light) - Transmission will not shift gears.

Possible Causes

- Low transmission fluid level - Dirty transmission fluid - Faulty 2-3 Shift Solenoid valve - 2-3 Shift Solenoid harness or connectors - 2-3 Shift Solenoid circuit is open or shorted

When Detected

The P0757 code is detected when the gear required by the ECM does not match the actual gear when vehicle is driven.

Tech Notes

When the a transmission solenoid is stuck on, in most cases the problem is not the electrical part of the solenoid; the problem is foreign material obstructing the mechanical function of the solenoid or the flow of the fluid through the transmission valve body. If the transmission fluid is very dirty, it is recommend changing the transmission fluid and if possible removing the transmission pan for further diagnosis. Excessive debris or metal particles on the transmission pan could be an indication that there is a transmission mechanical failure and that the transmission will need to be rebuilt or replaced.

Description

2-3 shift solenoid valve is turned ON or OFF by the Transmission Control Module (TCM) in response to signals sent from the park/neutral position (PNP) switch, vehicle speed and Engine Control Module (ECM) (throttle opening). Gears will then be shifted to the optimum position.