What does it mean?
P1751 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Transmission Shift Solenoid 'A' Circuit Malfunction .
Symptoms
- MIL (check engine lamp) on with a transmission warning
- One shift missing or arriving very late, often with an RPM flare
- Harsh, banging change into a particular gear
- Limp mode limiting the transmission to a single gear
- Poor acceleration and higher than normal fuel consumption
Likely causes
- Open or shorted shift solenoid A winding
- High resistance connection, corroded terminal or a broken wire in the drive circuit
- ATF leaking into the case connector and corroding the pins
- Solenoid stuck by varnish or a particle held in its seat
- Sticking shift valve in a worn valve body bore
- Contaminated fluid and a restricted filter reducing apply pressure
- Module driver stage failure, only after the solenoid and wiring test good
How to fix it
- Check fluid level, colour and smell before touching the electrical side
- Compare commanded gear with calculated gear ratio on live data during a road test
- Command shift solenoid A with a scan tool and confirm the gear ratio responds
- Measure solenoid resistance at the case connector and compare with specification
- Check the drive circuit for continuity, short to ground and short to battery
- Drop the pan and inspect the solenoid, its screen and the filter for debris
- Replace the solenoid or valve body after verification, then road test through all gears