P3046critical severityPowertrain
DCT Mechatronic Unit Internal Fault
on 2012 Tesla Model S 85 kWh Single Motor RWD · RWD
What this code means
The mechatronic unit (combined TCM and hydraulic valve body in DCT transmissions) has detected an internal electronic or hydraulic fault.
Symptoms
- Check Engine Light
- Transmission warning light
- Multiple gear selection faults
- Erratic shifting behavior
- Limp mode in fixed gear
- Loss of drive intermittently
Common causes
- Mechatronic electronic board failure
- Internal solenoid failure
- Hydraulic valve body wear
- Pressure accumulator leak
- Temperature sensor within unit failed
Diagnostic steps
- Read mechatronic unit internal fault codes
- Check hydraulic fluid level in mechatronic
- Monitor solenoid commands vs responses
- Test temperature sensor readings
- Perform mechatronic self-test sequence
Repair notes
Replace or rebuild mechatronic unit. Some manufacturers offer refurbished units. Requires special filling and bleeding procedures.
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Other Powertrain codes on this vehicle
P0070
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P0071
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P0072
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P0073
Ambient Air Temperature Sensor Circuit High
P0115
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ECT Sensor 1 Circuit Range/Performance
P0117
ECT Sensor 1 Circuit Low Input
P0118
ECT Sensor 1 Circuit High Input
P0119
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P0125
Insufficient Coolant Temperature for Closed Loop Fuel Control