pablo123

Hi
Can someone tell me exactly how LIM speed limiter works.

Does it use the brakes to slow the car to keep to limit set or does it use the engine / gears?

When accelerating and limit reached the acelerator pedal does not respond past limit. Does fuel get transferred to the engine for acelerator presses past the limiter?

Is it bad to drive with LIM feature on permanently?

N_Jay

Since the throttle is electronic, I would bet it just backs the throttle down to hold the speed.

pablo123

I would have thought so too holds speed, but how is the car slowed down using brakes or engine / gears?

Can anyone clarify this for sure?

N_Jay

Does it slow?
Or does it just suddenly stop accelerating?

u001elg

Interesting question.
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The cruise control works on a graded approach for decelerating... (I.e. - It will first close the throttle, then open torque converter clutch, downshift the transmission and then finally apply brakes via ABS module to maintain a given velocity.)
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I can't say as God's honest truth that the maximum speed limiter works in an identical manner, but my 1st reaction is that MB would utilize a similar approach.
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With that said, the W164 is generally pretty challenged to maintain maximum velocity for long distances on anything but a relatively straight, flat road free of traffic congestion. Here in PA, we don't have highways that could sustain permanent "LIM" velocities.
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If you are in a part of the world that can sustain the necessary conditions to reach and maintain maximum velocity - then yes the LIM feature is designed to keep your speed to within the aerodynamic and/or regulatory mandated maximum speed and should not hurt your ML.

pablo123

Thanks for the detailed response......a combination of throttle, transmission, then brakes, makes sense.

My point is it is probably better to use LIM for long down hill (50kms limit) over 500m distance than keeping my foot on brake continuously trying to keep to speed limit for the entire distance.

N_Jay

Do you mean the LIM, or the cruse control?

pablo123

I mean LIM speed limiter not Cruise Control.

Great feature I use on a few long hills where Police hang out to make some easy cash.

N_Jay

How do you set LIM?

pablo123

Hi,

It is in the manual.......the cruise control stalk if you press it in a yellow light comes on and LIM is displayed on the instrument panel.

Use the stalk up and down to set the limit and then it displays the speed set in the instrument panel.

Press the cruise control stalk again to switch it off.

Not sure what car you have but it is included on my ML (W164)

N_Jay

We don't have it.
I thought the LIM light was for markets that required a fixed speed limit.

chikoo

so after setting LIM, the vehicle does not go beyond the set limit even if you stomp on the gas pedal?

pablo123

It is a pretty clever feature it feels strange as it does not let you go past speed limit set if you push pedal nothing happens will not go past speed limit. However if you accelerate hard LIM gets switched off I guess to help you out of a tricky situation if needed.

I love the LIM function but my original post was asking if It damages anything if LIM were used all the time.

No one has given a proper answer.......I only use it going down long hills to stop me having to keep brakes on all the time and great for keeping to a limit.