No, they will not swap. The difference is the resistance value built in for the
length of the wire
going to the stop lights. 126 is longer than 123.
Why does this matter, you ask? Simple. The ground circuit for the cruise is the
brake light bulbs.
The resistance of the filaments and the wire to them is X value. When you step
on the brake, the
ground goes away [the stop lights light up].
MB got smart later on and made the same cruise amp for all. And added a
resistance plug to plug in.
The coding plug is different for each model.
As an example, go here:
and scroll down to the 2nd picture. 137 is the 'universal' amp. 140 is the
specific coding plug.
The cc is kicked off when the currend is sensed going through the brake
light bulbs. This is also why it's important to use the correct German
bulbs back there that absolutley have the right resistance.
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
Richard Sexton <See http://rs79.vrx.net for address> writes:
Interesting; thanks. I knew the CC disengaged when the brakes
were applied, of course. But I'd always thought that was done
with a switch underneath the brake pedal arm, kind of like the
downshift switch that's underneath the accelerator.
"There is one evil which...should never be passed over in silence
but be continually publicly attacked, and that is corruption of
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