Vehicles using electric/rear EM780 engine list:

Symptoms:
- Reduced electric motor power or loss of drive from the rear EM780 motor
- Warning lights on the dashboard related to electric drive or powertrain faults
- Unusual noises or vibrations from the rear axle area
- Inconsistent regenerative braking performance
- Overheating warnings or thermal derating during high load or extended driving

Diagnosis:
- Use Mercedes-Benz diagnostic tools (e.g., Xentry) to read fault codes specific to the EM780 motor and inverter
- Check for software updates or recalls related to the electric drive system
- Inspect wiring harnesses and connectors for corrosion, damage, or poor contact, especially around the rear motor and inverter
- Perform thermal imaging or temperature checks to identify overheating components
- Test motor insulation resistance and inverter functionality using specialized EV diagnostic equipment

Fixes:
- Update or reflash the motor control software to the latest version to resolve known bugs or improve performance
- Repair or replace damaged wiring harnesses and connectors to ensure reliable electrical connections
- Replace faulty inverter modules or motor components if diagnostics indicate hardware failure
- Clean and maintain cooling systems for the motor and inverter to prevent overheating
- Reset fault codes after repairs and perform test drives to confirm resolution

Prevention:
- Regularly schedule maintenance checks focusing on the electric drive system, including software updates
- Avoid prolonged high-load driving conditions that can cause thermal stress on the motor and inverter
- Keep the vehicle’s cooling system in optimal condition to prevent overheating of electric components
- Promptly address any dashboard warnings related to the electric drive to avoid further damage
- Use authorized service centers familiar with Mercedes-Benz EQ models for repairs and diagnostics to ensure proper handling of the EM780 system