2009 Mercedes-Benz SL550 Electrical system Problems
- Complaints
- 3about this part
- Share
- 20%of 15 total for the year
- Median mileage
- 60,000miles
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 3 complaints about the electrical system of the 2009 Mercedes-Benz SL550, 20% of the 15 complaints for this model year. Where a mileage was given, the median is 60,000 miles. 1 a fire, according to the filers.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“The contact owns a 2009 mercedes benz SL550. While trying to exit the vehicle, the door handle fractured and all of the doors automatically locked preventing the contact from exiting the vehicle. The vehicle was taken to a dealer. The technician diagnosed that the computer's theft system engaged once the door handle fractured and needed to be reprogrammed. The vehicle was repaired. The manufacturer was made aware of the failure. The failure mileage was 60,000.”
NHTSA complaint #10700587, filed 2015-03, 60,000 miles“I'm reporting a SERIOUS SAFETY ISSUE affecting all Mercedes-Benz R230 series SL roadsters, model years 2003–2012, of which approximately 85,000 were sold in the United States: • There are numerous reports on R230 SL owners' online forums that an electrical device located in the trunk of these vehicles known as the BCM [Battery Control Module] is prone to CATASTROPHIC FAILURE and melt-down. • The failed BCM can subsequently CATCH FIRE – potentially destroying the vehicle and endangering lives and property nearby. See photos attached from one SL owner's experience. …”
NHTSA complaint #11701077, filed 2025-11“This particular model 2009 Mercedes SL 550 hardtop convertible 5.5 liter motor has two batteries and accessory battery that battery that’s located in the trunk in the main starting battery that’s on the firewall. These batteries are both new in OEM recommended. If the car sits for 24 hours, it will not start. The electrical system is completely drained. There are many forms describing the same issue but yet the SL model is not included in a civil lawsuit. Mercedes-Benz definitely knows they have an issue in somehow it needs to be rectified.”
NHTSA complaint #11495761, filed 2022-12Related service bulletins
- 11015640Mar 5, 2025Complaint During a phone call, the called party has difficulty understanding/cannot understand the driver, or interference/background noises are audible to the called party…
- 11008091Sep 28, 2024Complaint During a phone call, the called party has difficulty understanding/cannot understand the driver, or interference/background noises are audible to the called party…
- 11000705May 31, 2024Battery Control Module needs replacement due to electrical overstress. Incorrect charging procedures and battery maintenance. Remedy Proper care and maintenance of the electrical…
- 10166105Jul 10, 2014The electrical wiring harness is trapped between the height adjustment gearing and the cushion frame.
- 10048279Nov 1, 2012Mercedes: camshaft adjustment solenoid may leak oil due to settling properties of seal and the engine wiring harness will be retrofitted with four adapter harnesses as a…
- 10033070Dec 16, 2009Xentry (mercedes): engine warning lamp is currently on or was on and a delay fault of the camshaft adjust to current or stored in the engine control unit. Models 171, 203, 209…
- 10016687Mar 31, 2009Abc visit workshop displayed in instrument cluster and hydraulic fluid leakage. *tt updated 5/14/09. Models 215, 220 and 230. Model years unknown.
Electrical system: other model years
| Year | Complaints | Share of year |
|---|---|---|
| 2009 | 3 | 20% |
| 2007 | 3 | 19% |
Other parts of the 2009 Mercedes-Benz SL550
← All problems reported for the 2009 Mercedes-Benz SL550
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 31, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology