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After using Launch Control, I understand that the car must be driven a certain DISTANCE before LC can be used again. Is this true and if so what is that distance?

Some people say it's TIME dependent instead. What is the truth?
 

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Ashok Arora said:
After using Launch Control, I understand that the car must be driven a certain DISTANCE before LC can be used again. Is this true and if so what is that distance?

Some people say it's TIME dependent instead. What is the truth?
It's based on various sensors which decide whether you can use it or not. If you drive hard for a period of time it won't work at all untill things have cooled down. At least that's my understanding - at the launch this happened in the car I was driving
 

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According to M6 owner it is distance dependent, can anyone confirm from their M5 owners manual?

http://www.m5board.com/vbulletin/showthread.php?t=56589

"Some (new) info that I learnd from the manual:

- According to the manual each gear has a given speed range. If you fall short of the particular speed range SMG shifts down automatically (in all drive modes). Apparently you can't stay in 6th gear (for a long time) while driving 50 km/h, for example.

- After each use LC is deactivated for a defined distance (not time, as I thought) that must be covered before it is active again.
"
 

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I thought the only dependant was HEAT.. I read in an article somewhere that there are sensors in the drivetrain that monitor the heat the whole time..

I think one M6 article said the M6's drivetrain heats to almost 600 degreees celcius when using launch control.. and until the system shows that its cool it will not allow another launch control..
 

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No, it's distance.

Read about this in Wheels Mag today (Australian review). The reviewer stated

"...To protect the clutch and other drivetrain componenets, SMG's launch control won't re-engage until four cool-down kilometres have been completed..."

Not sure if it's the same for you Euro guys, but I assume it would be.
 

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I dont know about 600 degrees C. That sounds way too high. Aluminium melts at 660 C, so it would probably be deforming at 600 C. Aluminium alloys melt at 600 C. Things must get hot in the drivetrain, but I would expect a lot of the heat to be generated in the clutch, and not too much in the rest of the drivetrain.
:cheers:
 

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i used it twice before 2 days.after i did 1st time i made a 5 kilometer run in a normal driving and used again.how many times should clutch resist.
 

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Discussion Starter #12
I love it when people bump my four year old threads :D
 
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