Page 1 of 1

Rear right ABS sensor wire is "damaged". Cost est

PostPosted: Fri Oct 06, 2006 5:09 pm
by Feu
I posted the following on one of the BMW forums, but seeing as I got some excellent tire, handling etc. feedback here on a previous thread, I thought I would ask for feedback here again.

I just got new tires installed on my '04 325xi.
The tire center said that, while replacing my tires, they noticed that the rear right ABS sensor wire was "damaged".
It was (apparently) rubbing against something (I believe the manager said against the brake or against the wheel).

The ABS fault warning light does NOT come on, meaning the ABS system is, currently at least, working properly.
Unfortunately I don't know the extent of the damage to the sensor wire, since they installed the new tires before I could see it.

Does anyone here have an idea roughly how much replacing one wheel's ABS sensor wire would cost?

I realize that the cost can vary (greatly) depending on the dealer, but even having a ballpark would help me know what to expect when I bring it in to the dealership next week.
They coincidentally have a free fall inspection, which includes checking the brakes. I just received the notice via e-mail this week, so the timing is good.

Perhaps I should have asked if I could speak with the person who installed my tires, to ask how bad the damage was.
Although I probably wouldn't know whether that indicated a safety risk or not.
The fact that they took the time out to mention it indicates it probably needs to be replaced.

When I mention it to the dealer, I'll say "scraped" as opposed to "damaged" and let them
decide what needs to be done, rather than ask for a replacement right away.

I am going to check google a bit more for recalls to make sure it isn't a known issue, as a 5 series had a recall for a bolt issue that could cause wire damage.

Any feedback on rough repair estimate (I won't hold you to it of course:) ) or on what the implications of this damage could be (I don't know much about ABS wiring) would be appreciated.

Thanks in advance!
I really appreciate the excellent replies I got last time around.

PostPosted: Fri Oct 06, 2006 6:14 pm
by Ian
Are you sure the tire guys didn't damage it? That might be why they put the tires on before showing you.

I don't know much about ABS sensors, but if its just the wire, it shouldn't be that much. That is if you don't have to replace the whole thing. They'll still stick you for labor though.

PostPosted: Sat Oct 07, 2006 12:37 am
by Dartman
As long as the wire isn't shorting out to something and not hacked in half it will probably continue to work. You might want to pull that tire and see what's really up, might be able to tape or put a dab of something on the bad spot to keep anything from going farther. Tie it up if its rubbing, just make sure it can move with whatever it needs to if apliable.

PostPosted: Sat Oct 07, 2006 1:36 am
by Feu
Thanks guys!

Ian,
I don't believe it was them, since they were up front about it, even though there is no discernible way to tell (car functions fine and ABS diagnostic light turns off, as it should, a second or two after starting the car).
In addition, some work was done a few years ago after a young driver with a 10 year old car and a right front headlight out (which severely contributed to the incident) smashed into my legally parked car (7 months old at the time).
It is possible that the body shop didn't tie the wire properly in place and that it has been slowly getting scraped / rubbed ever since (~ 32,000 - 34,000 miles).

BMW inspected it after the work, to certify it so as to maintain the warranty, since this is their approved body shop.
I doubt they'll admit that this is how it happened and that they should have caught it
when they thoroughly inspected the car after the repair.
The good news is that the repair was otherwise excellent and everything has been fine since (there was one minor cosmetic issue that cost about $50 or $60 to fix, that they missed at the time - I couldn't prove it, since it had been a while since the repair.
Other than that it has not had a single issue since the repair which was over 2 years and 32,000 miles ago.

Hopefully it won't cost too much to fix.


Dartman,
Thanks for the suggestion.
I may take the wheel off tomorrow, just so I can see the extent of the damage, especially since I can't get a loaner tomorrow and I don't want to spend half my Saturday sitting in their waiting room again.

The good news is the new tires are great, much better than the OEM tires, even though I only have 20 miles on them (500 mile break-in was mentioned in a tirerack.com post).
The reviews were excellent all around (#1 in its class); it had not one weakness, which made it a no brainer.


Now I just need to figure out the best tire pressure.

The manual says
front / rear
30 / 35 for up to 4 passengers (this is what I went by, since I usually drive alone)
35 / 42 for 5 passengers + luggage

I read some posts on bimmerforums where the people who posted all seemed to put more than the recommended (minimum).
My father's dealership or tire center also put a lot more air in his SUV's tires. He ended up settling for something in between the two.

PostPosted: Sat Oct 07, 2006 9:47 am
by bill
You may want to consider using a heat shrink tube for the wire repair. The tubes can be purchased in various sizes and (depending on the kit) with a brass splice lug for splicing the wire. If you must splice the wire, I would recommend the lug type that has a set screw for the connection instead of the crimp type. The only negative that I'm aware (for all kits) is that the wire must be reasonably straight at the repair location.

Generally speaking, there are two types, one is insulating only and the other insulates and waterproofs the repair.
Some examples- Link1 , Link2

The kits can be found at auto parts stores, electronic stores or electrical supply store. It's best to call the stores prior to making the trip and mention the wire size to the salesperson..

PostPosted: Sat Oct 07, 2006 10:50 am
by Feu
Thanks Bill.
That's a very nice idea, although I don't own a heat gun (yet at least).

Speaking of checking the damage:
I only have a 'cross' lug wrench and don't have a torque wrench to measure the torque on the lug nuts after tightening them.
If tightening them by hand and not being able to check the exact torque is not an issue, assuming that I tighten them fully without overdoing it, I'll take the rim off today and see what I find in terms of wire damage.

PostPosted: Sat Oct 07, 2006 2:46 pm
by Dartman
I've never used a torgue wrench to tighten mine either and so far no wheels have fallen off or been damaged as long as I remembered to tighten everything :wink:
Doesn't hurt to recheck after a few miles either. Bills idea on shrink tubing is a good one, a good hairt dryer will get hot enough to work or even a match if its a safe area to do that.
Most shops use a wrench to tighten them just right and in some case not overtighten, also to not get sued becuase somebody didn't get em all properly tightened if something happens later.

PostPosted: Sat Oct 07, 2006 5:22 pm
by Feu
Thanks again.

Before reading this post I was in my garage checking it out.
With the help of a flaslight, I managed to see the wire, without removing the wheel.
One section has been wrapped in electrical tape.
It was indeed right up against the underside of the rim.
I didn't see any mounting points that I could use to keep it from getting close to the wheel.
I couldn't find this wire on any of the other 3 wheels.
I ended up simply moving it a bit and seems to, temporarily at least, be staying about half an inch away from the rim, although nothing is preventing it from settling back against the rim.
If I had better access, I would carefully remove the tape to see the extent of the damage, but it was hard to get to without removing the wheel.

I will keep an eye on it till I bring it to the dealership.
If they come up with a high estimate I'll simply bring it to an indepdent mechanic my family has been using for years, who saved me a bundle over a Toyota dealership one time, after he checked the car and said 90% of the stuff they wanted to do was no necessary.


I tried jacking the car up for better access, but I kept jacking and the tire didn't lift of the ground at all.
I then heard a light noise, so I stopped, even though it may simply have been something shifting. I didn't want to take any chances...
I hadn't loosened the lug nuts, because I just wanted easier access to the wire from behind,
plus I just wanted to see how things went first.
I lowered it again and decided I will just wait and ask dealership to check it out when they do the free fall inspection next week.

After lowering it, I got nervous because the right side of the car (side I had jacked up) was slightly higher than the left.
I tried bouncing it a bit (sitting in back seat),
but it didn't seem to help.
I then backed the car out of the garage to make sure everything still seemed fine and at that point, the car automatically adjusted itself by lowering itself (the right side) back into position!
I am not sure what system that was or whether driving it helped adjust the rear right suspension (slightly)...
I checked and the rear of the car was again completely horizontal.
I do not have an adjustable mode suspension, so it couldn't have been that.

PostPosted: Sun Oct 08, 2006 8:39 am
by Feu
Quick update:
I found out that the suspension adjustment after jacking is normal (for my suspension type at least) and that, as I found out by backing it down the driveway, the wheel angle (which was the cause of the uneven car) re-adjusts itself on the control arm after a bit of driving, in my case a few feet down the driveway was sufficient to get things back to normal.

I may take the tape off the wire today by lying under the car again (NOT jacked up for safety's sake) to check the extent of the damage.
If only the outer jacket is frayed, I could simly tape it up properly (or better yet use some sort of sleeve / jacket).
The biggest problem then would be finding something to attach it to, so it doesn't rub against the wheel continually.
I also don't know if this specific wire requires any slack for proper operation when driving or braking... That would make shifting it an unwise move until I have confirmed it is fine to do so.

I'll probably take some digital photos and attach them to this thread...

PostPosted: Mon Oct 09, 2006 3:12 pm
by dodecahedron
Feu wrote:I found out that the suspension adjustment after jacking is normal (for my suspension type at least) and that, as I found out by backing it down the driveway, the wheel angle (which was the cause of the uneven car) re-adjusts itself on the control arm after a bit of driving, in my case a few feet down the driveway was sufficient to get things back to normal.

yeah that's normal, since when you lower the car down it's not symmetrical (one side having been raised and when you lower it it doesn't come down just the way the other side is).

as per your ABS issue: i would take the car to a certified dealer/service center and have it repaired. it might be more expensive, but that's a safety mechanism and i wouldn't mess with that.
my 2 cents.

PostPosted: Mon Oct 09, 2006 9:28 pm
by Feu
Thanks dodecahedron!
I just came to check for updates to the thread.

I already made an appointment this morning with the BMW dealer's service dept, since they have a free fall check-up special anyway.
They will even drop me off at home and pick me up when it is ready (even though I am not exactly down the block), since they don't have a loaner for the date I requested (tomorrow).
I nicely mentioned that I had been hoping to get it in sooner than Thursday due to the fact that it might get worse and was a potential safety issue (i.e. if the cable were to break).
The girl was nice enough to quickly oblige with the ride offer.

The only thing I did, yesterday afternoon, was wrap some transparent packing tape around the electrical tape as an added measure of protection.
I didn't want to play around with it more than that, since I don't know where it is supposed to rest and the access is a pain (had to lie under the car). Even if the cable isn't damaged, I would need them to route it properly...
It hopefully won't cost much (fingers crossed).

On a side note:
I also noticed, while under the car, that the thick brake cable (not the same as the thin ABS cable on the other side, that this thread is about) on the other wheel (i.e. left rear) was resting against part of the car.
The cable in question was in perfect shape at the contact spot, so that part of the car probably doesn't move (i.e. no rubbing against the cable). I noticed that the angle of
the bracket that holds it in place in one spot was a little off 90 degrees (unlike the other side where there was no cable contact).
I was thinking of adjusting the bracket a tad (simple procedure with a pair of pliers) but I decided to wait and have them look at it at during my service visit, since it will be an easy fix and I didn't have a tool with me when I was lying under the car (not jacked up of course) the same time.


I'll post an update tomorrow with the final cost.


Thanks to everyone for the feedback!

PostPosted: Tue Oct 10, 2006 2:00 pm
by Feu
Well, kudos to BMW!
They fixed the problem and it cost me nothing since it was covered under warranty!
I have only had the car serviced there, which may have helped with the work being covered under warranty.
In any case, I am very happy.

It was actually the brake lining sensor wire that had popped out of its housing and had become damaged from rubbing the rim etc.
It was not connected to the caliper.

Today they replaced the rear brake pads and rotors under the 4 year free maintenance warranty, since they were at minimum spec and also replaced the rear right brake lining sensor cable (there is one in the left front and one at the right rear).

They had replaced the front brake pads and rotors during a previous service.

They found nothing else wrong during the fall free inspection.

Thanks again for all the tips!

PS: On top of it all they washed it and cleaned the interior (which is much better than your average car wash) and even dressed the new tires I got last week (i.e. shined them).

Too bad I have to work today; it is the most wonderful day outside (3 people already commented on it).