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2002 E39 ASC BRAKE ABS lights on => Diagnostic Procedure & Parts Location

1M views 1K replies 213 participants last post by  MeisterSchnitzelBrau 
#1 ·
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.)


 

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#599 · (Edited)
http://www.bimmerfest.com/forums/showthread.php?t=613800

Heres my story..

Does anyone know the functions of the passenger side front sensor?? It says gearbox, but my car is a manual 5spd. Would that make a difference? I had my abs module repaired and all im getting now is a bad sensor right side.
 
#600 ·
I have posted this same info on the Xoutpost for the X owners and I thought, i'd post it here as well, since the things are same in the E53 and E39 (I also have a 528i)

I have an original Bosch 5.7 module installed in my BMW X5 4.6iS. This module was once repaired in Moscow, Russia (not Moscow, Idaho!!!), when the car was there and the -40 degrees temperatures got the best of the module. Recently I was towing a U-Haul 5x8 covered trailer (using the original BMW towing package installed on the vehicle from the BMW NA, 40 miles total towing distance), and the DSC, BRAKE and the ABS lights came on. As it happened during the tow, I got a brief message that the DSC INACTIVE, did not get that verbaige since then. Since there is no speed signal, all speed related functions are dead. As I drove the car since the towing, I would get the issue intermittently, once there will be no problem, the next moment the problem is there, I do get the trifeca of the lights, randomly get transmission into LIMP mode, and eventually set some codes in the Service Engine Soon.

So, I suspect the module is acting up again (when the temperature is at operating range, the problems start), and I need to remove it and to send it off for a repair, and hopefully, it can be repaired.

My problem is rather trivial - out of the 6 bolts: I was able to loosen up 5 and the #6 bolt broke off my Torx 20 bit and got the inside the torx part in the bolt stripped (almost looked like a Hex, but hex key would not work on it). It is the top left one, the one that is relatively easy to get to.

I went to home Depot, they sold me some "extractor" tool for $20, that is the "best on the earth", but it did not help.

Any suggestions on removing that last bolt?

I was thinking about stopping by a shop (meineke, midas, or whatever) and asking the guys to help me remove it... Do you think it is feasible?
 
#601 · (Edited)
I have posted this same info on the Xoutpost for the X owners and I thought, i'd post it here as well, since the things are same in the E53 and E39 (I also have a 528i)

I have an original Bosch 5.7 module installed in my BMW X5 4.6iS. This module was once repaired in Moscow, Russia (not Moscow, Idaho!!!), when the car was there and the -40 degrees temperatures got the best of the module. Recently I was towing a U-Haul 5x8 covered trailer (using the original BMW towing package installed on the vehicle from the BMW NA, 40 miles total towing distance), and the DSC, BRAKE and the ABS lights came on. As it happened during the tow, I got a brief message that the DSC INACTIVE, did not get that verbaige since then. Since there is no speed signal, all speed related functions are dead. As I drove the car since the towing, I would get the issue intermittently, once there will be no problem, the next moment the problem is there, I do get the trifeca of the lights, randomly get transmission into LIMP mode, and eventually set some codes in the Service Engine Soon.

So, I suspect the module is acting up again (when the temperature is at operating range, the problems start), and I need to remove it and to send it off for a repair, and hopefully, it can be repaired.

My problem is rather trivial - out of the 6 bolts: I was able to loosen up 5 and the #6 bolt broke off my Torx 20 bit and got the inside the torx part in the bolt stripped (almost looked like a Hex, but hex key would not work on it). It is the top left one, the one that is relatively easy to get to.

I went to home Depot, they sold me some "extractor" tool for $20, that is the "best on the earth", but it did not help.

Any suggestions on removing that last bolt?

I was thinking about stopping by a shop (meineke, midas, or whatever) and asking the guys to help me remove it... Do you think it is feasible?
Get yourself a small strong bit made for steel or similar, and a corded drill and start drilling away,.....good luck.
Btw, i just used an extractor set for the first time and it worked like a charm. However, I dont know if youll be able to use one due to the angle of where the bolt is on the abs module. Try anyway.
 
#603 · (Edited)
Brake Pressure Sensor

Anybody have a spare brake pressure sensor I can buy or borrow to test on my car? I had my car scanned and the brake pressure sensor triggered the fault code 249 times.

P.S. I live in the L.A. area.
 
#604 ·
Bluebee i went to that entire shenanigans , i remember that song "12 days of christmas" on the first day my ASC, then my DSC, and then my ABS, finally my speedometer stop, so it's Christmas,,,,, my control panel is will lit and my speedo won't give me a speed reading , my odometer stick at 79,499miles, but I continue to drive my ultimate driving machine , like you I been to the stealer, fine BMW doctors but can't fix the problem, unril finally I met the best guy in town who told me to bring it to his shop AVOS in Glendale it takes a grande drip star bucks to wait, and TGI done. It's the elusive ABS UNIT was change.
 
#605 ·
Bluebee i went to that entire shenanigans , i remember that song "12 days of christmas" on the first day my ASC, then my DSC, and then my ABS, finally my speedometer stop, so I thought it's Christmas,,,,, my control panel was will lit and my speedo won't give me a speed reading , my odometer stick at 79,499miles, but I continue to drive my ultimate driving machine , like you I been to the stealer,to a fine BMW doctors but can't fix the problem, until finally I met the guy in town who told me to bring it to his shop AVOS in Glendale it takes a grande drip starbucks for wait, and TGI done. It's the elusive ABS UNIT was faulty most of the time itwas replace.
 
#606 · (Edited)
i remember that song "12 days of christmas" on the first day my ASC, then my DSC, and then my ABS, finally my speedometer stop
I understand. The intermittence of the trifecta, coupled with myriad false readings from various diagnostic tools, plus the unfortunate variability of results with DMMs, makes the trifecta a seemingly difficult task to diagnose.

The simplest way I can state what we learned in this thread is:
0. If you have the bifecta or trifecta ...
1. Test the four wheel speed sensors using the quick test at the ABS control module harness using a 'good' DMM - if any one sensor is off from the rest - test that sensor at the wheel well. If more than one tests bad, then suspect your DMM or your probes (switch DMMs & try again, try different paper clips). Replace the one that tests bad at both the harness and wheel well (rarely will more than one will be bad). Always use the wheel speed sensors from BMW or our sponsors. Never Ebay unless you are really good at testing them upon receipt.
2. If the sensors tests good in this quick 5-min DMM test, then one could still be bad - but that's not likely - so move on to the ABS control module. Open it up with a knife or Dremel tool and probe with a toothpick to see if the 7th silvered wire has lifted off its bondpad. If it has - either resolder the wire connection (not easy!) or simply have the ABS control module rebuilt by the recommended rebuilders.
3. If you still have the trifecta after that point (very rarely will you need to get this far - but I think Quicksilver99 did), then re-test the wheel speed sensors using any of the six proposed (slower) tests in this thread. Replace the one that tests bad, (his problem, IIRC, was aftermarket wheel speed sensors that were bad but which tested good in the quick test).

If you wish to use fancy schmancy diagnostic tools for the testing, then be advised of all the admonishments in this thread (mostly by Bill, 540iman) about their limitations and false readings.
 
#607 ·
For the record, folks on the E46 forum are using this thread to diagnose their trifecta issues ... however the location of the ABS control module on the E46 is apparently in two different locations depending on the model year.
- E46 (1999 - 2006) > Where is the ABS Module located in our engine bay?

1. In the "drug bin"
2. Under the master cylinder



 

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#609 ·
Excellent ABS control module replacement information was summarized by Jared over here this week:
-> E39 (1997 - 2003) > ABS module issue

My statement was only in reference to our E39 modules.

Correct, our E39s use the Bosch 5.7 module, which has A LOT of problems, including the 7th silvered wire. That's only a small portion of the failures with the unit though. Since that is pretty much the only fix that can be easily DIY'd, it's what you see talked about the most on the forums. Unfortunately, there's a lot of other components that fail in the module (bad IC, blown caps, fried transistors, etc). I think since you and I have two different perspectives, we each see skewed results. I talk to customers every week who have unrepairable modules so I rarely ever see or hear of the 7th wire failure (other than on the forums obviously). With your excellent thread, you see a lot reports back with 7th wire success. Since the OP's module can't even be talked to, I'd about put money down that his main IC is toast. When you get other symptoms, such as the computer reporting a bad wheel speed sensor, it is usually a lifted wire or small component failure.

I finally opened up the module I have at the shop and did not find the 7th wire lifted. Without breaking out my scope and meter and checking some of the basic components, I don't think I'll get anywhere with it. There wasn't anything obvious fried, so I'm afraid it's the main IC that went (another common failure). I didn't pitch it, but put it back on the shelf for now. As my bad luck would have it, my wife's 540 just started having the intermittent trifecta. I have not had time to troubleshoot it, but I'm hoping it will be just the 7th wire. It comes and goes, which makes me think it has to be something like a cold solder joint but I'll still check the sensors. Pretty frustrating when both of our 540s had DSC issues within a few months of each other. It's funny to hear people complain about how needy an E39 is and here my dumb butt has two.

Now back to your question....

The new Bosch modules that we sell are not the same as what was shipped with our cars. A few years ago I saw the part number change, and since then, we haven't seen another failure. Sometimes manufacturers fix small problems, never changing the numbers, and the end user never really knowing anything was changed. When they go to the trouble of changing part number, a big design change was usually implemented. I've never opened up a newer part number, but I'd like to know what they've done to try and battle the heat related problems. Did they add heat sinks, go with different components, insulate it better, or what?

I'm pulling the numbers from my head here, but the Bosch number used to be something like 0 265 950 002 but now it is 1 265 950 002.

Does that clear things up? I sincerely apologize, I thought I had discussed the part number change enough that it was wide spread, but I guess it has been quite some time since I've brought it up. Do you think that is something we should add to your wonderful thread? I know it doesn't necessarily help with troubleshooting, but it is an informational piece to let everyone know they are the same module, one is just a newer updated version of the other.

As always, THANKS BLUEBEE! :thumbup:
Jared
 
#610 ·
^^^ Excellent information.
 
#611 ·
Big chase, all of the wheels have the Abs sensor behind the hub. Sometime the wires are dry rote and touches causing the abs and traction control lights to come on. The speed will act up also. I had to manually shift my automatic trans in order to get where I was going. You can get good prices on eBay. Thy this before getting to much in debt.
 
#612 · (Edited)
You can get good prices on eBay.
I wouldn't replace a wheel speed sensor unless/until I measured it to be bad ... and never more than one ... but I'd read this before buying wheel speed sensors on Ebay:
- What parts to always get OEM (1)

See why here:
- Quick99Si's non-OEM wheel speed sensors saga (1) (2)

EDIT:
Bobdmac recently posted a great ABS repair video to this ABS control module autopsy thread (1).

Something tells me Bluebee will love that video ...
bluebee; said:
It seems to help answer many of our questions:

  • What is the goop made of? (silicone)
  • How do you remove the goop? (some kind of clear liquid bath ... heated water? ... alcohol? some other solvent?)
  • What is the 7th silvered wired made of? (aluminum, apparently)
  • How is the wire rebonded? (ultrasonic bonder - but do they remove and rebond ALL the wires?)
  • How is the gel replaced? (it's just poured onto the board ... but is it heated first?)
These are their stated steps:

  1. Removing the old cap with a CNC machine (vacuuming up debris)
  2. Removing the old silicone gel (liquid bath)
  3. Visual inspection of bare die connections and removing all hybrid connections (what's a hybrid connection?)
  4. The aluminum and gold wire connections are made with an automatic ultrasonic bonder
  5. Creating new connections for all hybrid connections and damaged bare die connections
  6. The units are filled with a new high specification silicone gel
  7. A new cap is assembled and a protective cover is placed (on the back solenoids) for transport
  8. The unit is tested on our "Vision 3" which uses an automated script program to run the tests
  9. PASS!
EDIT:

Key questions:
Q: What's a 'hybrid' connection?
Q: What's the clear liquid in the bath?
Q: Do they really remove all the gold & aluminum wires & add new ones back? (wow)

PS: Here's an E38/E39 video of the simple removal of the ABS control module for those who have never removed one:
 
#614 ·
New to this forum but I come from another BMW forum that does not have much on this topic. 2002 525i with only the DSC light on. No abs or brake warning lights and the ABS works fine. Had a 006 brake code so I replaced the right front wheel speed sensor hoping that would solve the DSC light but it didn't. Anyone else have only a DSC light on with no other faults?

Thanks,
Alan
 
#615 ·
Here are some details of my issues with DSC:

Vehicle: 1998 e38 740iL (manuf 9/97)
Problem: DSC light ON, no other lights are on. Not sure if ABS works (haven't tried to check...:)..)
Codes: DSC system shows code P40 - Potentiometer.
Troubleshooting done;

  • Checked for any other codes with respect to speed sensors and such and did not find any
  • Pressing DSC button on dash does not do anything
  • removed negative terminal of battery and reconnected in an effort to reset DSC light did not result in anything. DSC light still solid ON
  • Replaced ABS module (complete with the Aluminium part at the back of the module) with another used but apprently working one from a 1998 e38
  • Bled the brake system.
  • However the DSC light is still ON.
  • When I took it back to the independent mechanic, he still reads P40 and he informed me that his system does not have a way to reset/code/programme the DSC module
  • Talked to someone I know at BMW dealership who checked with the BMW mechanic and infomed back that in fact the VIN needs to be coded into the new (used albeit) module. He also informed that the independent should be able to programme this. However if the independent is not able to then they may be in need of an upgrade on their software...:)

At this time rather than taking it back to the independent (who is not able to code the ABS module) I am thinking of using the same money towards the BMW dealership's coding of the ABS module. Waiting for the indication on how much it costs. I also got the Brake bleeding system from Harbor Frieght and will bleed the brakes one more time, just in case.

Separately I have tried to install INPA using instructions on this and other websites but have not been successful since I am using Windows 7 and don't have a Win XP laptop anymore. Tried the VmWare VM route however that is excrutiatingly slow. Don't have the patience to use that, besides it did not install in the VM properly and that too needs me to buy a license from VmWare after the trial is over.

Any ideas from anyone will be helpful. Will update once I reach another step.

Cheers for now.
 
#617 ·
As a cross reference for the record, today, an update was posted to this thread where, again, the 10-minute quick test failed to diagnose what turned out to be TWO bad wheel speed sensors.
> E39 (1997 - 2003) > Traction Control Kicks In at a Few MPH, then Trifecta Lights -Tried Everything? Help!

Okay, it's been a while, but I finally got back to it and the problem is solved. Turns out that the codes 6 and 7 were accurate. Hard to believe, but both front sensors were bad! I found replacements on eBay for <$20 each, so I figured I would give it a try. They were so dry rotted that when I took the old sensors off, the mounting ears just fell off. (BTW, they passed the DVM tests.) Cleaned the surfaces, installed the new sensors, and the lights went off. What a relief! So I guess the lesson learned is not to assume there is only one problem. The lights have been on for about a year, so I guess in that time the front sensors must have failed, even though they weren't the reason for the lights in the first place. Thanks to everyone for the help!
For the record, here are the latest bestlinks:
- How to diagnose the BMW amber ABS BRAKE DSC/ASC trifecta or bifecta (1) & what are all known options when your ABS control module is bad (1) & Quick99Si's explanation of why the 10-minute wheel speed sensor diode-action quick test doesn't always work, especially on brand new non-OEM wheel speed sensors (1) (2) & explanations by 540iman as to why the fancy diagnostic tools very often (extremely often, like almost all the time) fail to properly diagnose the trifecta or bifecta (1) (2) (3) (4) (5) (6) & where to get the fancy schmancy diagnostic tools for free once you're aware of these limitations (1) & an ABS BRAKE DSC trifecta brake pressure sensor diagnostic DIY (1)
 
#618 ·
I have yet to have time to cure my trifecta of lights but I have a new symptom. When it gets above 95 degrees or so outside my warning lights will go out and everything will seem normal. But then after a few minutes I feel my ABS pulse under normal braking, the lights go back on and my ABS no longer works. I'm now thinking it's not a speed sensor problem but a control module issue. Just curious of any ideas why high outside temps would impact this for the positive and give me a break from all the yellows on my dash?
 
#619 ·
ideas why high outside temps would impact this for the positive and give me a break from all the yellows on my dash?
Sure. It's just an idea ... but almost everyone agrees the 7th aluminum wire lifting off its gold bondpad is heat/vibration related, at least in the beginning.

Some folks even proved that the issue is heat related using a hair dryer.

I don't know if there is a good way to freeze the ABS control module to test but if you can figure out how to cool it, then you could turn the trifecta on and off at will with successive heat/cold applications without ever leaving your garage.

QUESTION FOR THE TEAM:
What's a good way to cool the ABS control module in the garage?

 
#620 · (Edited)
For cross reference, a nice steering angle remove and replace DIY was posted today, with a dozen beautifully annotated pictures:
-> E39 (1997 - 2003) > Replacing steering angle sensor
Here's the steps I took to replace my steering angle sensor. Do so at your own risk. I'm not a mechanic.

The process took about half an hour. My DSC light was on, so I scanned the codes and got a 90 degree difference of wiper too large steering angle sensor error. The error wouldn't clear and always came back.

The first step was to remove the lower drivers side dash and floor panel. I forgot to take pics of this, I'll see if I can add them later.

The next step is to crawl underneath the dash and look up. You'll see the coupler that joins the two steering columns together. Mark where the coupler joint is with respect to the steering column shaft attached to the steering wheel. If you don't your steering wheel could be at a slight angle when you put it back together.

Undo the nut and bold that clamps the coupler to the shaft. Grab the lower shaft and push it into the floor (on it's axis). It will push into the socket shaft on the floor.

Take a note how the steering angle sensor is situated. Unplug the steering anglesensor and slide it of the shaft.

I took my steering angle sensor apart and removed the spindle. I noticed that one of the sweeper arms on the spindle was broken or worn down (careful they're fragile). This most likely explained the 90 degree error. I picked up a working steering angle sensor from the junk yard, swapped out the spindle and re-assembled mine. I figured this would save the coding step.

I slid the fixed steering angle sensor back on the shaft, plugged it in and pulled the two steering shafts together noting where I previously marked them. Put the nut and bolt back in and tightened it. Plugged in the laptop, clear the codes and took it for a spin.

The 90 degree error went away and now I had a plausibility error. I ran a lew adaption. Started the car and while slowly rolling forward turned the wheel fully in one direction then the other. Took the car out for a spin, dcs light stayed off and no errors. I took out the steering shaft coupler nut, added some locktite before re-tightening the nut then assembled the lower dash. I've put 2000 klm on the car since then and no DSC issues.

On a side note it took me longer to remove/replace the lower dash then it did to separate the two steering shafts, remove/replace the steering angle sensor.

I didn't need to remove the steering wheel or drop the whole steering column.
 
#621 ·
There are so many different threads, I'm not even sure this is the correct one to post in, but here goes:
I have the dreaded trifecta of lights on my 2003 530i for the past week. Three lights illuminate intermittently, with a minimum of 2 (DSC & ABS), but mostly the ABS, DSC, and BRAKE all the time.
I don't have the time to mess around, so I'm going to have the ABS module repaired through BBA Reman via eBay. Their price is on special for $98.89 today and I just figured I would get it done since this is the most likely failure. If not, it's a $100 gamble and will eventually pay off on a car with +112k miles.
(The sale price is good from 9/24/12 until 10/1/12).
I just removed the module per instructions found elsewhere on these forums and thank everyone for contributing to the DIY and their other valuable input. Doing so made my life so much easier and saved me a lot of time, money, and aggravation.
I'll post an update when the I receive the module back in a week or so.
Thanks again everyone!
 
#623 ·
I'll post an update when the I receive the module back in a week or so
Keep us informed. As we admonish everyone, please DO ask them by phone what they found, and if they replaced any components and let us know what they told you.

Crossing my fingers that a) my module is rebuildable and b) it cures the problem.
Same advice as above. While it's on their test jig, give them a call and ask what they replace.

It helps if you marked prior the two bolted-in assemblies on the back of the module.
 
#622 ·
I took the plunge yesterday and ordered up a shipping label from BBA reman'd for my ABS module. Was on sale through yesterday for $98 and change! Got my shipping label in my email and will ship it out in the next day or 2. Crossing my fingers that a) my module is rebuildable and b) it cures the problem.
 
#626 ·
Bluebee,
I didn't even look at the unit, just installed it and went on my way. It was starting to rain and just wanted to get it on and drive. (No garage).
I've had no problems so far and expect everything to be fine.
Inspection is due in December so there should be no issues.
Will keep posting to this thread if anything new comes up.
Thanks again!
 
#627 ·
The Trifecta Is Back!

It's been just under a year since I successfully replaced my DCS module with a new one (not a repaired or rebuilt one) and the trifecta is back.

The original module lasted 11 years so I can't imagine the new module has failed after only 11 months (I don't want to believe it anyway). I hope there are other things at fault. I'll have to reread the various threads to find out what else causes all three lights to come on.

Has anyone else had the trifecta return within months of a successful repair? What was typically the problem?
 
#630 ·
Has anyone else had the trifecta return within months of a successful repair?
Not many. Most of the repairs seem to work (whether they be the 'rebuilt' module or the brand new modules). The rebuilders generally give a decent warranty; not sure about the new modules (I'm not a big believer in warranties - but if you have one - make use of it).

Wouldn't the car need to be moving before it knew a sensor wasn't reporting wheel speed?
Dunno. I could imagine, say, a shorted wheel speed sensor (or an open, or anything in between) delivering the wrong signal input to the initial test routine of the ABS control module - even without the vehicle moving.

The wheel speed sensors and the ABS control module are the two fragile components of the ABS system, but, as you know, there are over 20 sensor inputs to the system which can go bad.

Most of the time though, it's either the wheel speed sensor (rarely, if ever more than one at a time), or the module itself.

Details in post #48 of this thread:
- E39 trifecta diagnostic DIY
 
#629 ·
Thanks. That would be great if it's just a wheel speed sensor. The problem is the lights come on shortly after turning on the ignition before I ever start moving the car. Wouldn't the car need to be moving before it knew a sensor wasn't reporting wheel speed? Unless it can tell based on simple continuity. I'll have to read more about the speed sensors.
 
#631 ·
In the E38 forum, this highly pictorial 2012 DIY for replacing wheel speed sensors may come in handy:
- DIY Wheel Speed Sensor Replace

04-03-2012, 03:08 PM
Miss BimmerLV

S P O I L E D
BMW CCA Member
Join Date: Jan 2011
Location: La$ Vega$, Nevada
Cars: Left / Right Foot
Posts: 2,122


*******> ********>
DIY Wheel Speed Sensor Replace

Hi there....

Does your "DSC" , "ABS" and/or "Brake" Light illuminate ???

Do you feel a funky motion on your brake pedal????

Chances are...you Wheel Speed Sensor Needs replacing.

& Today I will teach you how to do so...

So lets get started!

You Will Need:

Some Hex wrenches, Some Dielectric Grease....and of course some Wheel Speed Sensors!







* Alright...so when your cluster looks like this..its time to do something about it.



* Pop the wheel of your choice off...For TODAYS example....we will be doing BOTH FRONT wheel sensors... Jack the car up....and turn the wheel FARTHEST to the side you will be working on. This will give you the ULTIMATE clearance you need to work!



* BEHIND the wheel hub...you will find ONE, 5mm Hex bolt. Undo the bolt....and you might have to wiggle the sensor a bit to ajar it loose...No pressure...just take your time. You some pliers if you have to!





* Next......Follow the sensor wire up a bit..you will find that is its snuggled into place out of harms way...simply remove from the holding bracket.



* Once you remove the sensor from below....you will find that YEARS of road grime have accumulated. REMOVE will wire brush.





( So fresh and so clean clean! )



* Once you have taken care of down below. Its time to TOTALLY remove the sensor. Locate the junction box housing BOTH the Brake Sensor AND Wheel sensor plug. Pry the tabs to open the box.



* Locate the DARKER colored connector. THAT is your wheel speed sensor.



* The connection is held in place by a REALLY small tab. Chances are..after YEARS of road grime..and water..and dirt...it will prolly just CRUMBLE away like mine did. So PLEASE PLEASE PLEASE be gentle. Worse case scenario ....You will have to order NEW connectors all around. ( Like someone else I know! )



* Simply disconnect...and insert the NEW sensor. Make sure you have a good connection with a "SNAP"
Then before you replace the sensor on the bottom..place a dollop of dielectric grease to smooth things over.





* Now route the cable accordingly..Place your Wheel back on....and guess what....



You DONE!!!!!!

The OLD Sensors....CRACKED and brittle EVERYWHERE. No wonder the ABS light kept flickin on and off!



*******> ********>
 

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#633 · (Edited)
It will come in handy when I get to it this week.
I debated opening a new thread on just replacing the wheel speed sensors for that - but it wasn't my material - so I didn't think it fair.
So far, 250K people have found this thread (have viewed it anyway) - so - if they get this far, they'll get all the information.
With almost 650 posts and that many eyeballs, pretty much all the garbage ideas have been weeded out by now.

To my knowledge, NOBODY has failed to solve their trifecta or bifecta, and, if we have to pick one person we owe a major share of the credit to, it's Bill - aka 540iman - who gave us the original quick test for the wheel speed sensors AND the ABS control module autopsy AND the rationale why the fancy schmancy diagnostic tools seem to almost always fail when it comes to the trifecta.

Thank you Bill! And Happy New Year to all!
 

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