Oh my. My 2002 BMW E39 has these three lights lit on my
instrument cluster:
- Triangle (is it ASC or DSC?)
- Brake
- ABS
I see there are lots of threads on this so I'm reading through them, but, they all seem to know already if it's ASC or DSC they're dealing with.
Am I dealing with ASC or DSC?
ASC (
automatic stability control) apparently senses 4-wheel differential speeds during cornering and cuts the
engine power via a second
throttle butterfly valve to help keep you from oversteering and spinning out in wet/snowy/unfavorable conditions. It may also apply the rear
brakes lightly in some situations. It apparently doesn't touch the
suspension at all. It has been described as
ABS in reverse. Reputedly, while
ABS controls the braking force at all four wheels, ASC + T controls the power delivery of the engine, and the way the rear differential distributes torque between the two back wheels only.
DSC (
dynamic stability control) in contrast, is apparently a suspension-control system which goes beyond Automatic Stability Control + Traction
by monitoring steering wheel movement, vehicle speed, transverse acceleration and yaw to register imminent instability when cornering. DSC then intervenes via the engine management system reducing drive torque and activating wheel brakes when necessary to keep the vehicle stable.
Having said all that, how do I know if my 2002 E39 has ASC or DSC?
(I think it's ASC but I need to know before beginning my troubleshooting.)
https://www.bmwfans.gr/forum/images/...tc1d1238-1.jpg
Thank you very much for the detailed test report!
BTW, we need to find out HOW they reattach those wires (solder or conductive glue) so we need someone to ask them while their ABS control module is on the test bench, especially if they have a WRE RP (wire repair?) performed.
BTW, there are some who say in the autopsy thread that the silvery colored larger wires are not actually steel; but I call 'em steel because the original Russian rebuilders in the references said they were steel (a magnetized needle would confirm that rather quickly, either way).
My guess is the wire repair was probably around here:
- removing "snot-like" goo from ABS circuit board <- ΠΟΛΥ ΣΗΜΑΝΤΙΚΟ!
https://www.bmwfans.gr/forum/images/...tc1d1320-1.jpg
Also, your experiences seem to mirror some of what we've reported, anecdotally, as shown below:
Quote:
BTW, while your ABS control module is out of the car (about 5 days), the following anomalies may occur:
- Brake/DSC/ABS trifecta solid yellow lights (on the instrument cluster)
- Service Engine Soon (SES) solid yellow light lit (on the instrument cluster)
- No ABS (upon hard braking under low-traction conditions)
- No traction control (DSC or ASC on lateral action)
- No speedometer (use a portable GPS navigation unit if you're worried about that)
- No odometer (again, use a portable GPS unit if this bothers you)
- No tripmeter (use a portable GPS unit if it's a worry to you)
- No cruise control
- OBDII diagnostic trouble code DTC P0500, i.e., bad speed sensor (clear by driving or with an OBDII scanner)
- No possibility of passing (California at least) smog inspections (until you replace the ABS control module & clear the DTC)
- No speed-sensitive automatic door locks (if enabled at the stealer)
- No GPS (if you have navigation)
- No mileage calculations on the instrument cluster
- No fuel consumption calculations on the instrument cluster
- No range indications on the instrument cluster
- No speed-sensitive radio (if equipped)
- No speed-sensitive wipers (if equipped)
- Erratic fuel gauge (especially when near empty, so keep the tank at greater than 3/4 at all times)
- Erratic transmission shifting (if automatic; if it bothers you, switch to manual shifting) |
Quote:
Very interesting!
For some reason, I hadn't seen your post until now.
The fact the wires may be aluminum will be useful for this ABS control module wire-repair thread:
-
removing "snot-like" goo from ABS circuit board Quote:
Originally Posted by geobrick https://s1.bimmerfest.com/forums/ima...s/viewpost.gif
The small wires are very likely to be gold and the larger silver color wires are either silver, aluminum or even platinum. See this pdf file from "heraeus contact materials" as a starting point. It's a company that makes wire for integrated circuits.
The bonding method is probably done by the wiring machine using some kind of highly localized heat as the wire is being pushed onto its contact pad). There may even be YouTube videos that demonstrate the process. There's a section in that document that talks about aluminum plated gold wire: "For special applications in which the reliability of gold is a "must", and where bonding at room temperature is obligatory, Heraeus offers aluminum coated gold wires.
The aluminum coating comes as an extremely thin layer. Aluminum coated bonding wires are a superior solution in order to improve the resistance in cycling tests, e. g. for automotive applications."
Here's another very informative link about the bonding process. If this is what's being done in our brake modules, then we just need the heat from the tip on a soldering iron to repair the bond (without any solder).
Now if I could only find the bad wire on mine... |
Quote:
I don't profess to understand it all, but, this thread purports to cover that topic in detail:
- What happens if you
don't code the VIN into a different ABS module
BTW, there were some FANTASTIC pictures of the insides of an ABS control module - and how to open it up neatly with a flat-tipped soldering iron ... over in the above-mentioned ABS autopsy thread today.
https://www.bmwfans.gr/forum/images/...13236217-1.jpg
