P1728high severityPowertrain
Transmission Slip Error
on 2021 Ford Mustang Mach-E Standard Range Dual Motor AWD · RWD
What this code means
The PCM/TCM has detected excessive transmission slip. The actual gear ratio does not match the expected ratio, indicating the transmission is slipping during operation.
Symptoms
- Check Engine Light
- Transmission slipping during acceleration
- RPM flare between shifts
- Harsh shifting
- Reduced fuel economy
- Transmission overheating
Common causes
- Low transmission fluid
- Worn clutch packs
- Faulty shift solenoids
- Valve body issue
- Torque converter failure
- Contaminated transmission fluid
Diagnostic steps
- Check transmission fluid level and condition (color, smell)
- Monitor transmission slip with scan tool
- Check line pressure
- Inspect shift solenoid operation
- Perform transmission fluid and filter service
Repair notes
Check fluid level first. Perform fluid and filter service. If slip persists, internal transmission repair or rebuild likely needed.
Other Powertrain codes on this vehicle
P0070
Ambient Air Temperature Sensor Circuit
P0071
Ambient Air Temperature Sensor Range/Performance
P0072
Ambient Air Temperature Sensor Circuit Low
P0073
Ambient Air Temperature Sensor Circuit High
P0115
Engine Coolant Temperature (ECT) Sensor 1 Circuit
P0116
ECT Sensor 1 Circuit Range/Performance
P0117
ECT Sensor 1 Circuit Low Input
P0118
ECT Sensor 1 Circuit High Input
P0119
ECT Sensor 1 Circuit Intermittent
P0125
Insufficient Coolant Temperature for Closed Loop Fuel Control