⚠️ Important Notice

By accepting, you confirm you have read and agree to our Terms of Use and Privacy Policy.

Your IP address and browser information will be recorded as proof of this acknowledgement. This data is retained for 12 months.

Mercedes W221 S500 Alternator Failure — Battery Warning — Mercedes-Benz S-Class 2006 | MyCarFault
⚪ UNSOLVED No confirmed fix yet · Be the first to help

Mercedes W221 S500 Alternator Failure — Battery Warning

Mercedes-Benz S-Class 2006 M273 5.0
On This Page: 🔧 All Repairs ⚠️ Avoid These 🔗 Similar Faults
⚡ Quick Summary
Severity Level
Medium
Safe to Drive?
✅ Safe to Drive
Safety Impact
No direct safety impact reported by owners
Urgency Level
🟡 Monitor Closely

The alternator on M273-powered W221 S500 fails at high mileage, leaving the car running on battery power. The red battery warning illuminates and electrical systems begin to fail within 20-40 minutes. The alternator is accessible but labour-intensive on the V8. Replacement unit costs £300-600; fitting adds £200-400.

Repair / Solution

No confirmed fixes yet. Share yours below.

⚠️ Wrong Diagnosis?

No commonly reported misdiagnoses for this fault yet. If you have replaced a part that did not fix this Mercedes-Benz S-Class 2006 problem, submit a wrong diagnosis report — it helps other drivers avoid the same costly mistake.

🚗 More About This Vehicle

📋 All Mercedes-Benz S-Class fault reports → 🚘 All Mercedes-Benz fault reports → 🔧 Browse all fault reports →
Explore more Mercedes-Benz models
Mercedes-Benz C-Class 29 Mercedes-Benz Sprinter 27 Mercedes-Benz E-Class 26 Mercedes-Benz A-Class 25

Help other owners by sharing your experience.

Your real-world fix helps thousands of drivers worldwide. Takes 2 minutes.

✅ Submit a Fault ❌ Wrong Diagnosis?
🔧
Usta
● Online