Drive Motor Inverter Performance Issue
The P0A79 code indicates a performance problem with the drive motor inverter, which converts DC battery power to AC for the electric motor. This can cause reduced power, stalling, or inability to drive. The issue may stem from faulty inverter components, wiring problems, or software glitches.
1. Symptoms You Will Notice
- Reduced motor power
- Vehicle may not start or move
- Check engine light illuminated
2. Most Common Causes
- Failed inverter module for motor 'B'
- Inverter overheating due to cooling system failure
- Deteriorated IGBTs (insulated-gate bipolar transistors) in the inverter
- Faulty inverter temperature sensor
- Corrosion or damage to high-voltage inverter connections
- Wiring or connector issues between the inverter and control unit
- High-voltage battery degradation affecting inverter performance
- Outdated or corrupted inverter software
3. Step-by-Step Diagnosis
Step 1: Scan for additional codes and check freeze frame data.
Step 2: Inspect inverter wiring and connectors for damage or corrosion.
Step 3: Perform inverter performance test using manufacturer-specific scan tool.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not safe. The vehicle may lose power or stall unexpectedly, posing a safety risk.
How much does it cost to fix?▼
Diagnosis typically costs $50-$150. Repair costs vary widely; inverter replacement can exceed $1,000.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.