Won’t start or crank

2005 MERCEDES BENZ SLK350
40,000 MILES • AUTOMATIC
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OROURKEP
  • MEMBER
  • 1 POST
My Mercedes won’t start. When you turn the key, the dash lights up, etc. but, no cranking or starting. I replaced fuse 52 and the starter relay but neither worked. Any ideas?
Aug 14, 2026 at 2:29 PM
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KRAKENAUTO
  • ✓ASE Certified Mechanic
  • 61 POSTS
  • ASE Certified Mechanic
Have we ensured the battery is good and fully charged?

Have you tried to jumpstart?

I know on those the ground strap is common to be compromised over time.

You can take a standard set of jumper cables. Clamp one black clamp to a clean, bare metal lifting eye/bolt on the engine block, and clamp the other black clamp to the dedicated negative ground post on the inner fender. Try cranking. If it starts, your ground strap is likely broken or corroded.
Aug 14, 2026 at 9:41 PM
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