Skip the auto shop - Our mechanics make house calls

Q: car won't start

asked by on

I've got a mercedes c300 2011 that won't start. I believe the battery is okay because when I turn the ignition all electrical components respond quickly as they should. When I turn the ignition I do hear what sounds like the starter motor spinning without engaging the flywheel. I have verified fuses that I believe are associated with the starter system and they also appear okay. Is this more than likely a bad solenoid?

My car has 50000 miles.
My car has an automatic transmission.

A: When the solenoid is energized, the pinion ...

When the solenoid is energized, the pinion gear is forced out by a plunger or lever to mesh with the ring gear. If the starter motor is spinning, freely, without the pinion gear engaging the flywheel, then something is wrong with the pinion gear assembly (lever, etc.) within the solenoid. Prior to condemning the starter though (best to replace starter/solenoid as one assembly) be sure that the solenoid is indeed getting 12.6 volt power, with NO voltage drop, when you turn the key to the start position. If your Mercedes Benz dealer sells rebuilt starters, that is the recommended source for this starter unless you have identified a reputable supplier in the aftermarket. Should you desire that a certified professional from YourMechanic diagnose this no start issue, and if necessary procure and replace the starter, by all means please schedule a mobile visit to get this taken care of.

Was this answer helpful?
Recommended services
Get a Quote

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car is shaking while idling and leaking coolant

From what you have described it sounds like a coil or spark plug fault causing a misfire. With the coolant leak, the most common cause would be a coolant hose or the radiator leaking. The two may be caused by...

Q: Clc 180 not charging replaced battery and alernator

Thank you for contacting us today in regards to your 2008 Mercedes-Benz not holding a charge. When the alternator and battery have both been replaced at the same time, a common culprit is either an issue with the battery cables...

Q: Air conditioning not cooling

A number of different things could be causing this issue. The most common cause is that the system is low on refrigerant. This would have been caused by a leak in the system. The first step would be to turn...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...