P0A1A: Motor Generator A - Performance
10 vehicles · 2 makes · $200-$6,500 repair
Most Reported On
P0A1A is an OBD-II diagnostic trouble code meaning “Motor Generator A - Performance.” This is a hybrid/electric powertrain code indicating a performance problem with motor-generator 'A' — typically the generator portion of the hybrid drive that produces electricity and helps start the engine. The hybrid control system monitors this motor-generator and its control electronics (inside the inverter assembly), and sets this code when the unit doesn't perform as commanded. It often points to a fault in the motor-generator control circuit, a current sensor, or the inverter/intelligent power module. You'll usually see a warning light and may experience reduced hybrid performance or a disabled hybrid system. This code is most commonly reported on 2019-2025 Audi A6 (Premium, Premium Plus, Prestige), 2019-2025 Audi A7 (Premium, Premium Plus, Prestige), and 2021-2025 Mercedes-Benz S-Class (S500, S580), plus 7 other vehicles, with repair costs ranging from $200 to $6,500.
Common Causes
Typical Repair Cost
Based on 11 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.
Diagnostic Tools
To diagnose P0A1A, you'll need an OBD-II scanner. Here are our recommendations at every price point.
ANCEL AD310 Classic OBD-II Scanner
by ANCEL
A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).
- Read & clear engine codes
- View freeze frame data
- I/M readiness status
- No batteries or app needed
BlueDriver Pro Bluetooth Scanner
by BlueDriver
Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.
- Enhanced diagnostics (ABS, SRS, transmission)
- Repair Reports with verified fixes
- Smog check readiness
- Free app (iOS & Android)
LAUNCH CRP123X OBD-II Scanner
by LAUNCH
A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.
- Engine, transmission, ABS, SRS diagnostics
- Live data stream & graphing
- AutoVIN for vehicle identification
- Free lifetime updates via Wi-Fi
Autel MaxiCOM MK808S Diagnostic Tool
by Autel
Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.
- All-system diagnostics (25+ modules)
- Bi-directional control & active tests
- Oil reset, EPB, BMS, TPMS, injector coding
- 7-inch touchscreen with Android OS
As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.
Vehicles Affected (10)
48V Mild Hybrid System Faults
MMI Infotainment and 48V Mild Hybrid System Issues
48V Mild Hybrid System Faults and Start-Stop Issues
48V Mild Hybrid System Belt-Alternator-Starter (BAS) Failure
48V Mild Hybrid System Battery Degradation
48V Mild Hybrid Battery Issues
Battery Drain from 48V System
48V Mild-Hybrid Battery Degradation and Faults
48V Integrated Starter-Generator / DC-DC Converter Failure Causing Sudden Power Loss and No-Restart
48-Volt Integrated Starter-Generator / DC-DC Converter Failure Causing Warning Messages, Limp Mode, or No Restart
48V Mild-Hybrid / Integrated Starter-Generator Failure Causing No-Start and Power Loss
FAQ
What does P0A1A mean?
P0A1A stands for "Motor Generator A - Performance." This is a hybrid/electric powertrain code indicating a performance problem with motor-generator 'A' — typically the generator portion of the hybrid drive that produces electricity and helps start the engine. The hybrid control system monitors this motor-generator and its control electronics (inside the inverter assembly), and sets this code when the unit doesn't perform as commanded. It often points to a fault in the motor-generator control circuit, a current sensor, or the inverter/intelligent power module. You'll usually see a warning light and may experience reduced hybrid performance or a disabled hybrid system.
What are the most common causes of P0A1A?
The most common causes of P0A1A are: Faulty motor-generator (MG) control circuit or current sensor in the inverter, Failed inverter / intelligent power module (IPM), Damaged or shorted high-voltage motor wiring or connectors, Internal fault in motor-generator A, Corroded or loose control-circuit connectors, Outdated or corrupted hybrid control software, Faulty hybrid/motor-generator control module (ECU). The specific cause varies by vehicle.
How much does it cost to fix P0A1A?
Repair costs for P0A1A range from $200 to $6,500, depending on the vehicle and root cause.
Which vehicles are affected by P0A1A?
Au7o has documented P0A1A across 10 vehicle models from 2 manufacturers: Audi, Mercedes-Benz.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.