I believe there are two bulbs, a small one for the rear side markers and
a dual filament bulb for the (rear) running and brake lights.
One ought to use the correct brake light bulb or the car's cruise
control may be adversely affected.
The circuit is set up for the resistance of a decent bulb, Use
a crappy one and neither it nor the cruise will work right.
The choppy cruise is a broken solder joint. Take it out and
resolder EVRYTHING on that board and 99% it'll perfect again.
Use German bulbs. The dealer has them and they're cheap.
Need Mercedes parts ? - http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
The cruise control ground circuit goes thru the stop light bulbs. When you step
on the brake, the
bulbs light and you lose ground. Cruise shuts off.
The cruise control has no other 'instant off' switch. If it has no ground thru
the bulbs, it cannot
The ground circuit is designed to operate thru the resistance of 2 OSRAM 21w
bulbs. US made bulbs
have different resistance values, some work some don't. Sometimes only 1 in a
box of 10 US bulbs may
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