P1783critical severityPowertrain
Transmission Overtemperature Condition
on 2021 Ford Mustang Mach-E Extended Range Dual Motor AWD · AWD
What this code means
The PCM/TCM has detected that the transmission fluid temperature has exceeded the safe operating range. Excessive transmission heat accelerates fluid breakdown and causes accelerated wear of internal components.
Symptoms
- Check Engine Light
- Transmission temperature warning light
- Harsh shifting
- Transmission slipping
- Possible limp mode
- Burning fluid smell
Common causes
- Low transmission fluid level
- Contaminated or degraded fluid
- Faulty transmission cooler
- Blocked transmission cooler lines
- Heavy towing or hauling
- Torque converter clutch not engaging (keeping fluid hot)
- Internal transmission failure
Diagnostic steps
- Check transmission fluid level and condition immediately
- Pull over and allow transmission to cool if actively overheating
- Inspect transmission cooler and lines for blockage or damage
- Check for TCC-related DTCs (P1740-P1744)
- Verify cooling system is functioning
Repair notes
Stop driving if transmission is overheating. Check fluid level. Service transmission cooler. Replace fluid and filter. Address any TCC issues.
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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