For those who drive with the ESP off (i.e., illuminated and disengaged)
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So, to defeat EDL, we could cause a brake temperature fault.
Jet, I assume that all other ABS functions still work, except EDL, when the brakes are overheated. If that's the case, one could determine what signal is required from the brake temperature sensors, intercept them and create a overheat fault indication. This should allow EDL to be defeated without disabling the ABS.
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Someone test if EDL comes off.. put one wheel on ice, turn off ESP, and gun it
If the car remains straight, EDL stays on... otherwise we can assume it gets turned off too.
EDL=The electronic differential lock (EDL) permits smooth, comfortable starts on road surfaces that do not have a uniform coefficient of friction. If a wheel starts to spin, EDL brakes it as necessary so that power is transmitted to the wheel with the better traction. EDL reduces tire wear and works up to about 25 mph (quattro®: up to about 50 mph). EDL is part of the Electronic Stabilization Program (ESP) and the traction control (ASR) .
So EDL is only on while moving from a start?? Or if you are doing 35mph and hit the accelerator on ice it will keep you straight?
EDL=The electronic differential lock (EDL) permits smooth, comfortable starts on road surfaces that do not have a uniform coefficient of friction. If a wheel starts to spin, EDL brakes it as necessary so that power is transmitted to the wheel with the better traction. EDL reduces tire wear and works up to about 25 mph (quattro®: up to about 50 mph). EDL is part of the Electronic Stabilization Program (ESP) and the traction control (ASR) .
So EDL is only on while moving from a start?? Or if you are doing 35mph and hit the accelerator on ice it will keep you straight?
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IIRC, EDL is turned off when ESP is turned off.
except when you apply the brakes, the system is programed to activate in case you might be in trouble and re-engages the system just in case you are.
Even if you have the system "off"
When I drive 30mph down the road and there is a patch of ice on one side and not on the other. I can floor it and have tire spin on the side with the ice when ESP is off. Same from a start. There is nothing happening to prevent wheel spin.
With ESP on, EDL would normally engage the ABS and stop the wheel spin. When ESP is on, you also get the ASR power cut so there is a lot happening all at once. And in slippery situations, you can almost go no where, with the EDL and ASR going on.
Not sure on the RS4 with the two stage system if it will disable the EDL with the ASR or at the ESP stage 2.
Even if you have the system "off"
When I drive 30mph down the road and there is a patch of ice on one side and not on the other. I can floor it and have tire spin on the side with the ice when ESP is off. Same from a start. There is nothing happening to prevent wheel spin.
With ESP on, EDL would normally engage the ABS and stop the wheel spin. When ESP is on, you also get the ASR power cut so there is a lot happening all at once. And in slippery situations, you can almost go no where, with the EDL and ASR going on.
Not sure on the RS4 with the two stage system if it will disable the EDL with the ASR or at the ESP stage 2.
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There is no brake temperature sensor on our cars. It use the logic built into its algorithm to ...
Deactivate the EDL. It's too bad because if there was such a sensor it could be easily modified to fool the ESP/ABS/EDL system.
There is perhaps another way to fool the EDL/ABS system but I never got around to messing with it.
Since EDL works only as a traction device it is automatically deactivated during braking. If you can fool the system into thinking it's braking by let say activating a brake sensor (the third brake light), then EDL should not work.
A couple of years ago I was about to embark on that project but I solve probably most if not all my EDL problems by installing my STaSIS LSD so the project was put on the back burner.
BTW, this as been done on NON ESP equipped cars.
There is perhaps another way to fool the EDL/ABS system but I never got around to messing with it.
Since EDL works only as a traction device it is automatically deactivated during braking. If you can fool the system into thinking it's braking by let say activating a brake sensor (the third brake light), then EDL should not work.
A couple of years ago I was about to embark on that project but I solve probably most if not all my EDL problems by installing my STaSIS LSD so the project was put on the back burner.
BTW, this as been done on NON ESP equipped cars.
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