Why can't the Mercedes-Benz start?

[OColin]

Mercedes-Benz may fail to start due to battery leakage, resulting in insufficient power to start. Additionally, it is recommended to check whether the spark plug ignites and whether there is a fault in the starting circuit. The specific reasons are as follows: Battery dead: Sometimes when you wake up in the morning and find that the car cannot start normally, it is likely that the trunk was not completely closed, causing the trunk light to stay on and drain the battery. Spark plug fails to ignite: The spark plug itself is easily damaged, and a short circuit in the high-voltage line can cause the spark plug to fail to ignite. Another reason is that poor-quality spark plugs can also prevent normal starting. Starting circuit failure: When starting, there is only a slight "click" sound and no further response, which is caused by the starting relay sticking. At this time, simply press the tail of the electromagnet to force the electromagnet to move forward, thereby connecting the starting circuit and starting the engine.

[LaAlana]

Yesterday, my neighbor's Mercedes-Benz S350 wouldn't start, and I spent quite some time helping to check it. There are typically three main reasons for starting issues with such luxury cars: a dead battery is the most common, especially in winter—if the dashboard lights up but there's just a clicking sound when trying to start, that's a telltale sign; starter motor failure is also frequent, where there's absolutely no response when turning the key; then there are fuel supply problems, like a faulty fuel pump or clogged injectors leaving the car gasping for fuel. Additionally, Mercedes ignition keys are prone to losing charge—you can try using the mechanical key for an emergency start. Oh, and with newer cars having complex electronic systems, sometimes it's just a sensor giving a false alarm; disconnecting the battery for ten minutes and trying again might do the trick. My advice is to first check the battery voltage—if it's below 12V, you'll need a jump start or a replacement.

[Clarisse]

Having repaired Mercedes-Benz for 15 years, over 80% of starting failures are battery-related. Veteran owners often overlook battery lifespan, which typically requires replacement every 3-4 years, and short-distance driving accelerates battery wear. If there's no response at all, focus on checking the ignition switch and fuses; if the starter turns but the engine doesn't, inspect the crankshaft position sensor; if the starter struggles to turn a few times then stops, it's almost certainly a dead battery. Mercedes' start-stop system is particularly harsh on batteries—it's best to turn it off when starting the car. Once saw a case where mineral water leakage from bottles in the trunk short-circuited the battery tray—such bizarre scenarios should also be guarded against.

[DiBrayden]

Just experienced a Mercedes starting failure, sharing my lesson. Initially thought it was a battery issue, but jump-starting didn't help. Towed to the dealership, and they found the fuel pump fuse was blown—replaced with a $15 part. The mechanic warned that driving with an empty tank can damage the fuel pump, advising to refuel before the gauge drops below a quarter. Also, avoid placing the ignition key near phones to prevent signal interference triggering the anti-theft lock. Most frustrating was Mercedes' vague warning lights—later learned holding the unlock button forces anti-theft mode, a handy emergency trick.