Mercedes-Benz has issued a massive recall affecting more than 354,000 vehicles from the 2015, 2016, and 2017 model years. According to the National Highway Traffic Safety Administration, some of those cars may be at risk of catching fire.
The problem with the vehicles is electrical in nature and is rooted in the starting current limiter, manufactured by Gruner AG. Like most limiters, this one is designed to manage electrical currents, protecting other components from being damaged and preventing fuse overloads.
Unfortunately in this case, it's the protector that needs protecting. NHTSA's defect bulletin explains that the limiter in these Mercedes-Benz vehicles isn't designed to handle the heavy current draw that may occur when an engine or transmission is damaged, preventing the car from starting:
"In the event the starter is blocked due to engine/transmission damage (e.g. hydro locked engine), a very high electric current would flow through the starting current limiter during the subsequent start attempt. Should the driver attempt to start the engine repeatedly despite the engine not cranking, the very high electric current draw might lead to overheating of the starting current limiter."
That overheating can cause nearby components to melt, and in worst-case scenarios, could result in a fire.
The list of vehicles included in the recall is long and, thanks to Mercedes-Benz's naming system, a little complicated. We've done our best to alphabetize it:
- 2015-2017 C300
- 2017 C300 Cabrio
- 2017 C300 Coupe
- 2015-2017 C300 4Matic
- 2017 C300 4Matic Cabrio
- 2017 C300 4Matic Coupe
- 2016 C350e
- 2016-2017 C450 4Matic AMG Sport
- 2015-2017 CLA250
- 2015-2017 CLA250 4Matic
- 2015-2017 CLA45 AMG
- 2017 E300
- 2017 E300 4Matic
- 2017 E400 4Matic Wagon
- 2017 E43 AMG 4Matic
- 2017 GLA250
- 2017 GLA250 4Matic
- 2017 GLC300 4Matic Coupe
- 2016 GLC300
- 2016 GLC300 4Matic
All told, there are 354,434 of those vehicles registered in the U.S.
Sadly, none of those vehicles can be repaired yet, because Mercedes-Benz doesn't have an ample supply of parts. Owners will receive interim recall notices in late March, which will alert them to the problem. The automaker expects to have parts on hand in July 2017 and will mail a second recall notice then.
That second notice will include instructions for scheduling service with Mercedes-Benz dealerships. NHTSA says that dealers will install an extra fuse in the electrical line to the starter, which will resolve the issue.
If you own one of these vehicles and have further questions, you're encouraged to contact Mercedes-Benz customer service at 1-800-367-6372. Or, if you prefer, you can call NHTSA's Vehicle Safety Hotline at 1-888-327-4236 and ask about safety campaign #17V114000.