I own a 99' 328i. For the last month when I start the car the ABS, ASC, Brake indicator lights stay on for the duration of my drive. My ASC will become deactivated during this time. The next time I turn on my car everything is back to normal and ASC works fine. It has been doing this sporatically for the last 2 months. Sometimes it goes 2 weeks without it happening but then it starts going again. I own a service manual but it does not explain what are the causes of this. As you all know BMW centers charge a bundle just to do a diagnostic check and I want some feedback from owners who have experienced this problem or aware of this problem.

I own a 99' 328i. For the last month when I start the car the ABS, ASC, Brake indicator lights stay on for the duration of my drive. My ASC will become deactivated during this time. The next time I turn on my car everything is back to normal and ASC works fine. It has been doing this sporatically for the last 2 months. Sometimes it goes 2 weeks without it happening but then it starts going again. I own a service manual but it does not explain what are the causes of this. As you all know BMW centers charge a bundle just to do a diagnostic check and I want some feedback from owners who have experienced this problem or aware of this problem.

Very simple most likely. If you drive in damp, or rainy weather sometime the water, or dampness can get into the sensors and cause them to trip. It is easy to check your abs system by braking hard if the brakes are past the 500 mile brak in already. If you feel the ABS system working then it should be fine. As with all OBDII compliant cars aka 1996+ cars I always recommend getting a reset tool, or better yet a OBDII scan tool so you can pull off all the codes yourself and save thousands of dollars over the life of your car!

Jared

Thanks for your feedback. I actually did a brake fluid flush about 2 weeks ago and the lights have not come on since. I bought the car used (from 3rd party) a year ago (25k miles) and I had not done a brake fluid flush (recommended every 2 years from my recollection). I hope that was the fix, maybe the brake fluid was too old and was impacting the ABS/ASC system test. I think your information was very useful though, maybe the car washes are causing this (I live in California where we get heat and little to no rain/humidity). Thanks, Jared!

You da man

Thanks for your feedback. I actually did a brake fluid flush about 2 weeks ago and the lights have not come on since. I bought the car used (from 3rd party) a year ago (25k miles) and I had not done a brake fluid flush (recommended every 2 years from my recollection). I hope that was the fix, maybe the brake fluid was too old and was impacting the ABS/ASC system test. I think your information was very useful though, maybe the car washes are causing this (I live in California where we get heat and little to no rain/humidity). Thanks, Jared!

You da man

No problem man, Where in Cali you at? I am trying to get my ass out to LA and open up a Euro perfomance shop!

Jared

Thanks for your feedback. I actually did a brake fluid flush about 2 weeks ago and the lights have not come on since. I bought the car used (from 3rd party) a year ago (25k miles) and I had not done a brake fluid flush (recommended every 2 years from my recollection). I hope that was the fix, maybe the brake fluid was too old and was impacting the ABS/ASC system test. I think your information was very useful though, maybe the car washes are causing this (I live in California where we get heat and little to no rain/humidity). Thanks, Jared!

You da man

Hi I have a 99 323is and the ABS/ASC light has come on and won,t go away. You said that you did a brake flush, was that all you did and did that fix the problem.

Hi I have a 99 323is and the ABS/ASC light has come on and won,t go away. You said that you did a brake flush, was that all you did and did that fix the problem.


You know what. It went away for about a month and it came back. Doing the same patterns. I'm kind of lost right now. I'm in the process fo getting and code reader and reset tool.

First, does the red "Brake" light come on? I assume not. If it is, drive carefully......or not at all, since you'll have no rear proportioning.

Second, these lights should come on in this manner (intermittent)for two reasons. Either sensors are losing contact intermittently or there is a vehicle communication problem.

Obviously, pull codes if you have the ability. If not, I would check:
-wheelspeed sensors - are they connected properly or is there water in the connectors?
-connections to the ABS unit under the hood - it's the component along the brake lines right after the master cylinder.
-Steering angle sensor - Did you do anything to the steering wheel?
-If it's none of that stuff, you'll need to pull codes for sure.

first, if ur problem is just the light and the ABS is active I can think of two possible reasons:
1. ABS light could come on due to the extra electrostatic charges bcuz of weather and this can solved by adding an earth wire to speed sensors at each wheel.
2. there was a manufacturing problem in the ABS module software for E` type cars released since 1996 as declared by the company and this can be solved by replacing the module