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Lowering, Zero-ing Travel Sensor Position, and DSC
Many of you guys know the DSC Sport controller is a plug & play solution that improves road comfort and track performance of the suspension. But did you know that DSC Sport controller can zero the factory level sensors(aka ride height sensors or suspension travel sensors) on the car? We refer to this DSC function as "Zero Travel" , meaning setting the positions of each of the four suspension travel sensors to zero(or static position) when the car is at rest. The DSC Zero Travel function can be very useful on cars with lowered ride height(via lowering springs or coilovers) or whenever a factory travel sensor is showing an irregular data value(which happens sometimes when the sensor is disconnected for other work), or when adjustable control arms are installed causing a change of level sensor position. The result of have an irregular data level from a sensor is potentially getting fault messages on the dash and in worst case unexpected behavior from systems on the car that uses this data(such as ABS and Stability Management). Granted that the factory threshold for irregularity of the level sensor data is pretty high, occasional we do come across unwelcomed behaviors from the affected system. PIWIS can of course zero the level sensors but most car owners don't have quick access to PIWIS. For those who are considering getting a DSC or already have a DSC the Zero Travel is a value-added function!
Here's example images of the factory travel sensors-
Here's a video to demonstrate the DSC Zero Travel procedure-
I heard the newest module zeros automatically if lowered and doesn't need this to be done manually is that true?
In regard to the DSC commanding the shocks' damping force, then Yes it can be viewed as such. Since DSC monitors the travel sensors' direction of movement relative to the previous movement and the velocity of each movement. It is entirely possible that each shock goes through a number of compression and rebound movements before it even approaches zero position so in this regard zero-ing doesn't matter. I think I have answered a question sometime in past on zero-ing for the purpose of damping performance that perhaps got misconstrued.
But in the regard to other systems on the car, No. If the car has stock ride height and stock suspension components then the presettings of the newer DSC right out of the box should be very close(and well within the range of factory threshold, which again is a very wide threshold). But none of the modules that I am aware can self-zero the sensor values for other systems of the car since it cannot distinguish the difference between having the car on a lift with all four wheels fully extended, or having the car on the ground with all four wheels loaded, or halfway loaded, or have one side of the car lifted by a jack the very first time the ignition is turned on. Let alone for ride height changes that car owners intentionally make.
I heard the newest module zeros automatically if lowered and doesn't need this to be done manually is that true?
Most cars with dynamically adjustable shocks will require a "Trim Height Relearn" procedure. If your not sure if your shocks are dynamic look for suspension position sensors, that is a good indication that your car is dynamic! From my experience most have no idea how important this is. I see the local domestic shop turn out Corvette's, Trucks, Camaro's, Mustangs......... they do a huge amount of work. About (2) years ago I put load levelers on my truck, which has magnehelic shocks, after doing so the ride was terrible, like a chuck wagon. The shocks had gone into a heavy load condition stiffening everything a tremendous amount as it believed I had a large amount of weight in the bed or towing. I asked the shop to recalibrate my ride height and they looked at me like I was crazy, "We have never done that before". So I took it to the dealer and had to teach them how to do the procedure as it was new to them also!!!!! Sure trucks are the extreme but absolute position does make a difference in all the other cars also.
Oh and one more pet peeve I have is adjusting headlights, if you lower or raise a vehicle adjust the lights, this is missed 9 times out of 10!
Most cars with dynamically adjustable shocks will require a "Trim Height Relearn" procedure. If your not sure if your shocks are dynamic look for suspension position sensors, that is a good indication that your car is dynamic! From my experience most have no idea how important this is. I see the local domestic shop turn out Corvette's, Trucks, Camaro's, Mustangs......... they do a huge amount of work. About (2) years ago I put load levelers on my truck, which has magnehelic shocks, after doing so the ride was terrible, like a chuck wagon. The shocks had gone into a heavy load condition stiffening everything a tremendous amount as it believed I had a large amount of weight in the bed or towing. I asked the shop to recalibrate my ride height and they looked at me like I was crazy, "We have never done that before". So I took it to the dealer and had to teach them how to do the procedure as it was new to them also!!!!! Sure trucks are the extreme but absolute position does make a difference in all the other cars also.
Oh and one more pet peeve I have is adjusting headlights, if you lower or raise a vehicle adjust the lights, this is missed 9 times out of 10!
Thank you for the great information. I have just installed the DSC controller in my 2013 Porsche Boxster S with PASM. I did notice an out of the box improvement however a few questions:
1. If I wanted to lower the car 10mm with PASM off and 20mm with PASM on is that possible? And if so how?
2. Are there any things I should definitely do?
Thank you for your assistance as I am brand new and need to learn.
I put your module in my 991.1S Porsche which I bought second hand w KW HAS springs lowering it 1 inch.
So today I zero’s the ride height sensors per videos online. Two small questions: (1) I did this in both Standard and Sport setting but didn’t see that done in video. It seemed more thorough to me. Correct?
And (2) My digital gauge cluster reported a change to headlights when I reset. Normal?
I put your module in my 991.1S Porsche which I bought second hand w KW HAS springs lowering it 1 inch.
So today I zero’s the ride height sensors per videos online. Two small questions: (1) I did this in both Standard and Sport setting but didn’t see that done in video. It seemed more thorough to me. Correct?
And (2) My digital gauge cluster reported a change to headlights when I reset. Normal?
Zero’ing covers both suspension modes.
It is normal for headlight service to display momentarily during the zero’ing process. This indicates the ride height sensors(which levels the headlights) are momentarily in service mode.
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PCA National Instructor
TPC Racing stats:
2023 Porsche Sprint Challenge 992 Cup Am Champion
2023 Porsche Sprint Challenge GT4 Pro-Am Team Champion
2022 Porsche Sprint Challenge 992 Cup & 991 Cup Champion
2020 IMSA GT3 Cup Challenge 2nd Championship
2018 IMSA GT3 Cup Challenge 2nd Championship
2016 IMSA GT3 Cup Challenge Champion
2013 IMSA GT3 Cup Challenge Champion
2006 Rolex-24 @ Daytona GT Champion
2004 Grand-Am SGS Class Champion