Hey guys. I am having a problem with my ASC light as it is always on.
Only the ASC light and I cant turn it of with the button.
What should I look into?
Mine does it sometimes. I think it's related to voltage or the unit possibly on its way out. Normally happens on a restart from the daily run, never on the initial cold start
Sent from my SPH-L720 using Tapatalk
Look into:
- wrong size wheel and tires (they can't be more than 3% different between front and back)
- dirty/broken speed sensor on each wheel
- failed ASC+T Hydro pump (if your car has ASC+T)
'93 850Ci - Mineralweiß Metallic
2001 740iL - Titansilber
ALPINA B7 -Alpinweiß III
...the price of cool ain't cheap!
Your ASC+T Hydro Pump has failed - good luck, those are hard to find.
'93 850Ci - Mineralweiß Metallic
2001 740iL - Titansilber
ALPINA B7 -Alpinweiß III
...the price of cool ain't cheap!
Has this car been sitting for a while? Mine did this after sitting a few months, and the "fix" was to drive through a couple puddles enough to (I assume) clean the crap off the wheel sensors. I think rust had built up on the rotors while sitting, and when I took it out for the first time after that all of it got scrubbed off and ended up on the wheel sensors.
Check the ASC cable. My cable had frayed and that caused the cable to 'stick', and made the ASC light come on.
Give it a poke - they usually get going again:
Timm..2007 E64 650i Individual Sport..1999 E31 840ci Individual Sport..ex owner of 2000 E38 740..1999 E38 740i V8 M62..1998 E38 735i V8..1993 E32 730i V8..1988 E28 518i
My BMW Repair YouTube Channel
My Current 840ci Sport Individual
My Current 650ci Sport Individual
My E31 Repair and Information Website
My E38 Repair and Information Website
My E63/E64 Repair and Information Website
Chase - Heroes to a generation
So i should Just make a hole in the relay and poke it with a screwdriver ?
That is like asking if you should jam a screwdriver through the fender into the Hydro pump and see if it fixes itself - we narrowed it down for you. You now need to do actual diagnosing on your vehicle and find the problem. When I had this problem 10 years ago, I narrowed down to the Hydro Pump and had to pull it and replace it. You can check the 4 wheel sensors pretty easily. The sensor itself rarely fails, but you need to look at the wiring too. Usually it is just dirt build up on the magnet - clean them off and see if the light goes out. If it doesn’t, then you will most likely need a new ASC hydro pump.
'93 850Ci - Mineralweiß Metallic
2001 740iL - Titansilber
ALPINA B7 -Alpinweiß III
...the price of cool ain't cheap!
Timm..2007 E64 650i Individual Sport..1999 E31 840ci Individual Sport..ex owner of 2000 E38 740..1999 E38 740i V8 M62..1998 E38 735i V8..1993 E32 730i V8..1988 E28 518i
My BMW Repair YouTube Channel
My Current 840ci Sport Individual
My Current 650ci Sport Individual
My E31 Repair and Information Website
My E38 Repair and Information Website
My E63/E64 Repair and Information Website
Chase - Heroes to a generation
Suggest check asc codes and go from there (http://www.bimmerboard.com/forums/posts/213216).
On my car, the MID displays the "Brake Assist" message and "Check" message. The cluster shows the (!) indicator. It comes on and goes off on a regular basis.
The funny thing is, every time when I flip the headlights, the "Brake Assist" message and (!) lamp on the cluster comes on right away. I had a leak in the pentosin system that I have recently fixed and have bled the system via the valve by the shock tower on driver's side.
The brakes are very mushy so I need to bleed the brakes. Not sure why turning on the headlights would trigger the Brake Assist warning to come on the MID.
Fatandre, start the ASC self-diagnostic.
I've read the manual, it was pretty easy.
It will blink on the dash, and you'll see.
I don't remember, you need to turn ignition with ASC button pressed for 10 seconds or something like that.
In my case, a very odd one, the system did not like the ASC+T/ABS control module. So it blinked to the last error - control module.
Everyone told me it must be an ASC+T pump. Nevertheless, I bought a spare ASC+T/ABS control module, installed and it was fixed.
The fun thing that the ASC module didn't answer to normal service tool diagnostics via the round plug. So self-diagnostics works!
p.s. For your interest, I've opened up the ASC+T/ABS module and it looked scary and perfectly fine. The scary thing is that there are many gel-celled processors, and it's all "made in Austria" which you don't see often.
Last edited by Diskovod; 07-28-2018 at 06:01 PM.
Thanks Diskovod.
How do you read the blinking?
Here are the instructions
https://imgur.com/a/hWxkyaZ
Please, save the images, it's likely they won't last forever, and they exceed bimmerforums size quota.
sadly I replaced my tandem pump for my ASC+t system and it seemed to fix the ASC+t light form coming on for months, then again it came back.
I'm looking to see why its back.
Have you bled your pentosin system properly by disconnecting the ABS module connection then bleeding the ASC+t nipple back into pentosin reservoir? I just did it again and it definitely helped make my steering groan a lot less again and braking somehow seems a little crisper, but still did not solve my ASC+t light, which comes on only after the car heats up. Never on a cold start.
I swear, my cars are like a girlfriend.
Sometimes its a rough ride, sometimes its smooth motorin'.
Sometimes she doesnt like how i treat her and sometimes i dont like how she behaves.
BUT at the end of the day, she loves it when I am inside her.
'91 Dinan 860 Stage III (new 6L engine)
'91 Dinan 850 TT stage III (brand new engine) 21st Century Tech meets 18th Century Dinan...
'91 850i 6sp (mint) (sold)
'90 Dinan 750iL TT stage III (Guido - The Beast)
'94 850 CSi The Detroit Auto Show car (restored to factory perfect) (sold)
'96 850Ci, The George Carlin car
''73 3.0 csi, '08 535i, '03 X5 4.6is
...and a few other non BMW cars
As if an 8 needs ASC+T. I can't imagine a driving condition when it would be necessary. I am considering disabling mine.
Desecrator of all things Sacred
I swear, my cars are like a girlfriend.
Sometimes its a rough ride, sometimes its smooth motorin'.
Sometimes she doesnt like how i treat her and sometimes i dont like how she behaves.
BUT at the end of the day, she loves it when I am inside her.
What is it that gets damaged in the ABS- ASC T unit?
They are pretty hard to source
Bookmarks