What model? On my w212 and a buddy's GLK, the front cig lighter slot does not power a standard charger. No idea why but it may be a weird Merc thing? Fuses seemed fine. My chargers have worked well in the other 12V slots without issue, so I keep it plugged into the console outlet.

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth