When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Ever since I purchased my car, a 2011 Carrera S that I got CPO in January 2018, I have been getting very early ABS engagement. This can happen backing out of my driveway going straight, so not over any sort of driveway imperfection or curb, as well as at 80mph with 20% brake pressure, or 40mph with light brake pressure. It happens in all conditions, whether 80* or 40* outside. I took it into my dealer this spring, they checked codes and did not see anything so I drove it like this during the summer, but it was quite unnerving. I took it into the dealer this October and had the tech drive it who immediately felt it. He started by taking another 997 they had and doing a multitude of things, including
Bleeding ABS Pump (actually cycling it, not just flushing the brakes)
Bleeding Brakes
Swapping wheels/tires with another 997 to be sure it is not wheel hop
Swapping YAW Sensors
Swapping Wheel Speed Sensors
Resetting and then Recoding the ABS Pump since just resetting it did not work
Unplugging ABS fuse (when removing this, ABS does not activate anymore, so we know it is related in some way to a sensor or the module)
New ABS Pump, direct from Germany ($3500+ labor so around $4200-4500 all in with labor)
After all of this, they thought they fixed the issue, but I immediately got it to replicate. It is starting to snow in Cleveland, so the dealer and I agreed to wait until the spring and have this looked at then. There apparently are other sensors that it could be, which they are going to look into this spring. They also mentioned it could be pads and rotors. As you can imagine, I am not very willing to spend $2000-3000 on pads and rotors from the dealer with install, when I have 6mm of pad material in the front, and 7mm pad material in the rear, with no cracking on the rotors, only a small lip. Granted, I can have a friend or shop do the brakes for less, but with that much pad material, I just cant imagine that being the cause. Porsche in Atlanta has been contacted and all they could think of was the ABS module, which was replaced.
That's an odd one. Not sure is your 997.2 has the same brakes as my wife's 05 C2S with big red brakes, but if so, I have lightly used rear slotted Sebro rotors and all 4 pairs of Hawk HPS pads that I'd sell pretty cheap. All you'd need is some new front rotors and you'd have a nice braking upgrade that would also let you test the pad and rotor theory without having to pay new prices. I'm up near Clemson in SC so only a couple hours from Atlanta.
Thanks for the offer, although I am actually in Cleveland, Ohio. Bought the car from Atlanta. I think I am going to hold off on doing any sort of pads and rotors until the dealer tries everything under CPO first. Also, I know my dealer really was encouraging me to use stock pads and rotors especially with this issue going on.
Would really appreciate it if you could come back and post an update. Most posters never update ther thread when an issue is fixed leaving the rest to wonder what the solution to the problem was. I’m also fighting with some brake issues on my car. Hope your dealer can figure it out.i would not be happy after spending $4k on a new abs module and still having same issues.
Premature abs engagement usually is caused by an erratic abs sensor signal. This can be caused by the sensor, sensor tone ring damage, loose tone ring, loose axle ect,. you can isolate which sensor is causing the problum using a scanner or lab scope. With a scanner you have to look for a variation in speed between sensors at the point of premature abs application. I usually use the wave form function and record the pattern of each sensor when the fault occurs. The faulty sensor will show up when compared to the others. Once the offending sensor is determined you have to look at the toothed tone ring carefully for damage or looseness. If all is ok then check the sensor ground. If all is ok, then lastly replace the sensor. The ABS modules for all practical purposes never fail.
Does the 997.2 have a tone ring with the teeth for the abs sensor? I believe the wheel bearing has a magnet on just one side which should be installed facing inwards. Could the bearing have failed or installed wrong?I could be wrong though.
Ever since I purchased my car, a 2011 Carrera S that I got CPO in January 2018, I have been getting very early ABS engagement. This can happen backing out of my driveway going straight, so not over any sort of driveway imperfection or curb, as well as at 80mph with 20% brake pressure, or 40mph with light brake pressure. It happens in all conditions, whether 80* or 40* outside. I took it into my dealer this spring, they checked codes and did not see anything so I drove it like this during the summer, but it was quite unnerving. I took it into the dealer this October and had the tech drive it who immediately felt it. He started by taking another 997 they had and doing a multitude of things, including
Bleeding ABS Pump (actually cycling it, not just flushing the brakes)
Bleeding Brakes
Swapping wheels/tires with another 997 to be sure it is not wheel hop
Swapping YAW Sensors
Swapping Wheel Speed Sensors
Resetting and then Recoding the ABS Pump since just resetting it did not work
Unplugging ABS fuse (when removing this, ABS does not activate anymore, so we know it is related in some way to a sensor or the module)
New ABS Pump, direct from Germany ($3500+ labor so around $4200-4500 all in with labor)
After all of this, they thought they fixed the issue, but I immediately got it to replicate. It is starting to snow in Cleveland, so the dealer and I agreed to wait until the spring and have this looked at then. There apparently are other sensors that it could be, which they are going to look into this spring. They also mentioned it could be pads and rotors. As you can imagine, I am not very willing to spend $2000-3000 on pads and rotors from the dealer with install, when I have 6mm of pad material in the front, and 7mm pad material in the rear, with no cracking on the rotors, only a small lip. Granted, I can have a friend or shop do the brakes for less, but with that much pad material, I just cant imagine that being the cause. Porsche in Atlanta has been contacted and all they could think of was the ABS module, which was replaced.
Does anyone have any idea what this could be?
Thanks!
Following. I also have a 2011 997.2 on which my ABS triggers far too easily. My dealer drove it and told me it is normal, but I do not believe that. My previous 911 was a 2003 996.2 and I never had noticeable ABS engagement. Please follow up as you find more! Thank you.
I am on here daily, so I will update everyone with what the status ends up being. This will not be solved until spring, when I plan to drop it off at the dealer and have them fix it until it is right.
The dealer has done live data logging, with no luck either.
ABS/PSM can activate on uneven surfaces, when one of the wheels has little or no-grip, even at very low speeds. Say, leaving sideways on the edge of an inclined driveway and a horizontal road, one of the roads may have little grip (or no grip) and ABS/PSM is triggered - perfectly normal.
ABS/PSM can activate on uneven surfaces, when one of the wheels has little or no-grip, even at very low speeds. Say, leaving sideways on the edge of an inclined driveway and a horizontal road, one of the roads may have little grip (or no grip) and ABS/PSM is triggered - perfectly normal.
Thanks for the input. I did take this into effect, it has been when not going over an inclined driveway edge or on a bumpy road. It has been on perfectly smooth roads. Having driven other Porsches, a Macan and a 997.2 Turbo at great length, neither experience the same issues which is why I think my car has an actual problem.
Thanks for the input. I did take this into effect, it has been when not going over an inclined driveway edge or on a bumpy road. It has been on perfectly smooth roads. Having driven other Porsches, a Macan and a 997.2 Turbo at great length, neither experience the same issues which is why I think my car has an actual problem.
No objection. It looks like your ABS/PSM system has a bug.
I have also had similar issues with my GT4 (attached link to post). Dealer couldnt resolve it and i have spent the last year and few months chasing my tail around this issue. I have logged wheel sensors and they are fine. My current view is that it is a problem with one of the sensors feeding into the ABS via the stability control system. I have been recently advised to check Steering Angle sensor and calibrate it as well as any other sensor that might feed into stabilty control.
I have also had similar issues with my GT4 (attached link to post). Dealer couldnt resolve it and i have spent the last year and few months chasing my tail around this issue. I have logged wheel sensors and they are fine. My current view is that it is a problem with one of the sensors feeding into the ABS via the stability control system. I have been recently advised to check Steering Angle sensor and calibrate it as well as any other sensor that might feed into stabilty control.
reading your thread makes me worried. I have a similar problem like you but with my rear brakes which don’t seem to bite the rotor hard enough. Front brakes are over braked and abs engages. I really hope you can diagnose and fix the issue. https://rennlist.com/forums/997-foru...ke-issues.html
Figured I would check back in and see if anyone has any ideas. I am probably going to take mine back in come March/April to have this hopefully permanently fixed.
Update: dropped the car off at the dealer. They are going to be working on it as time allows since they are thinking it is going to be a send data to Porsche and wait for response sort of thing. There is a regional field tech that has been assigned to the issue and is thinking it may be wheel bearing issue. Pretty sure it is the same one working on Nick Murray's case, so hopefully we will have some better luck than Nick has had.
11-25-2018, 01:19 PM
ABS Enagement Issue
