ABS Problems - Not sure how to proceed

[Michelle129]

Sorry if this post is somewhat long, but I'm totally lacking any mechanical knowledge and want to make sure I include all information!

I purchased a 2001 Tahoe back in March 2005. It ran great, no problems at all.

About a year ago, had to replace all 4 tires, couldn't afford new, so purchased some gently used ones. The garage I bought them at didn't have 4 of the same tires so he put a matching pair on the front and a matching pair on the back.

Approx. one month after that noticed the brakes starting to squeal and ended up having to replace both pads and rotors on just the front. Again, money was an issue so I had it done by a friend.

It wasn't too long after that, that my ABS and parking brake lights were coming on. At the same time my ABS started kicking in during slow braking(approaching crosswalk, stop signs, low speed driving in parking lots etc). The lights and the ABS kicking in were totally dependent of each other. My ABS could kick in and the lights wouldn't come on....or the lights would come on during normal driving...not when braking. The ABS kicking in and the lights at first were very sporadic. I could drive for days without either one happening. But as the months have passed it is now happening much more often and I had to bite the bullet and take it to a mechanic.

I first went to a franchise type garage and had them do a full brake diagnostic. They said during physical inspection, everything looked fine. They hooked it up to the computer and after 2 hours came back and told me that I wouldn't have to pay for the scan as their computer would not pick up any codes..and I would have to take it to a dealer.

The next day I took it to the dealer and after explaining the situation the guy was sure it was my wheel speed sensors and told me it would be about $400 to replace if that were the case. I was somewhat relieved as that was affordable. HOWEVER...after running all their tests, it was much worse news. They told me there was no power running to the BPMV and that I would have to replace both the EBCM and BPMV...at a cost of about $3000 with parts and labour (I'm in Canada). He said the scan code that was coming up was C0265. That obviously is totally devastating and unaffordable for me.

I can't help but wonder if they saw me coming a mile away and with my total lack of knowledge when describing the problem, if the mechanic knew he could run circles around me and get me to fork out all this money when it's not necessary. (OK maybe I'm grasping at straws...do mechanics still do that with oblivious women in this day and age?!) Trust me when I say I'm not a woman's libber and never cry chauvinism...but after watching a few poor seniors in line in front of me that came in for a simple oil change and leave with a bill over $400 for "necessary services"...It was a thought.

Anyways, what I'm wondering is if the tire replacement, or the brake replacement could have anything to do with the problem...and how to proceed from here before I have to give in and spend the $3000. It seems odd to me that if this part was totally burnt out, why the problems are only sporadic, not every single time I drive. Like I said I'm not mechanically inclined but I do know some people that could help me to check things out.

What steps should I follow from here? Thanks for any help at all.

Michelle

 

[jey_]

I would get a second opinion - try a different dealer. It could be a connection to the EBCM, rather than the EBCM itself - especially if it's intermittent like that. Another option is see if there is a good independent shop that would be willing to find a salvage/used EBCM and install it for you.

 

[Big Tap]

The EBCM is a problematic piece on these model SUV's and trucks. If you type EBCM into the Ebay search engine, you can find places to send yours in to have it rebuilt for about $160. They totally rebuild them with better internals that are much less likely to go bad. You can still drive your vehicle around while this is being done. I wouldn't recommend getting a used one because I've heard that although they're usually interchangable, sometimes units out of other vehicles cause the ABS light to still kick on for some reason. New units are around $600, not to mention, you're still using the old style internals that are known to prematurely go bad on both the new and used options.
This would be an easy do-it-yourself project, as the EBCM is located underneath the SUV, near the driver's side door. I think it's two plugs and four torx head screws to get it off. I think I had mine uninstalled in under 10 minutes.
I don't know much about the BPMV, but maybe someone else can chime in on that. Hope this helps a bit.

 

[00' 323]

Double check all the wiring cause my 04 silverado got a lift kit and the fukasses that installed it left my brake lines loose. after a while they worked themselves to the wheels and rubbed untill they shorted out the sensor due to the bare wires. the dealership said that i was out 750 to replace the wheel bearing cause the sensor and hub is one unit. that pissed me off since the part is only 89 bucks from an auto parts store. all i did was gave them my vin and had them vin check to parts and found the speed/abs sensor. dealerships are dumb.

 

[u2nv]

There is a common problem on these trucks n suvs haveing a bad ground under the drivers door on the front body mount there is a cluster of wires bolted down, take bolt out clean all paint off from this area as well as connectors, clean them real good then instead of old bolt that threads into frame get an actual bolt with a nut so it dont ever come loose again then once bolted and tight put some paint over area so it dont rust. unhook battery neg cable and let sit for 20 min and redrive if it comes back then yes you may need to replace module or you have bad fuse or wiring but try this first cheap easy and do it yourself fix.

 

[00' 323]

Oh wow, u2nv is dead on with starting simple. That will save you assloads of time. I might do this just because its an easy preventative maintenance idea! that damn little module... jack up the vehicle, take off the wheel, take off the caliber mounting bracket, take off the disc brake, bend the dust shield and shove a 6 mm hex wrench in there. then, reverse all that. Thanks u2nv!

 

[jroth142]

Wow! I was litterally in the process of typing in "abs problem..." in the search field when I looked down and saw this thread! I have an 02 z71' that I just bought about 3 months ago doing almost this exact same thing except I haven't seen any lights come on, just the actual abs on the occasional stop. Sounds like there's a few ideas out there to try to avoid a huge repair bill. I had a similar issue with my last car and it was the main reason I sold the stupid thing. I couldn't believe it when my truck started doing it the other day!! : (

 

[jroth142]

A friend of mine said he had a recall on his 2000 full size truck for this same reason. Any chance there's a recall out there for our tahoes?

 

[00' 323]

You can always google that. i know that there are some websites dedicated to protecting people from dealerships and they list any and all defects or recalls on any vehicle dated back to 1994/5 ish, im not too positive though.

 

[jroth142]

Well, I did some searching and it looks like there was a recall for a wheel sensor issue on the 02's at least, but I called my local dealer and unfortunately mine had already been done : (
I'm struggling with what to do next. I have no abs light (although my SES light came on a week ago but went off about 3 days later) but it has definitley gotten worse lately. The abs kicks on on nearly every stop. I looked up the EBCM's on ebay but I don't want to spend the money then find out it's something else. Is there any good way to determine if this is definitely the problem? I checked my ground under the drivers side door and it's not loose or anything, but I definitely have some rusting on my underbody (Midwest winter = lots of salt unfortunately).
I think the recall was for the wheel sensor though so I'm also wondering if something there may have gone bad/gotten dirty again.

Any help/advice would be appreciated before I bite the bullet and take it to the dealership. Thanks in advance!

 

[u2nv]

like i said in my previous post but this is new dont just check the ground and c if its tight and looks ok do the repair reguardless. Ive had a couple that look good to me and ive been wrenching for 10 years but you do the repair and the trucks dont come back so just clean it and rebolt it

 

[jroth142]

Thanks, I'll give it a shot. Do I still need to disconnect the battery if my abs light isn't on?

 

[Godti]

say Wha?

 

[jarhead0844]

I had to replace my EBCM when my park and abs lights lit up. I didn't have the problem of the ABS actually acting up, it just quit altogether. My cousin is a brake tech for a dealer and he told me this is a common problem with Tahoes. I was lucky to be able to get the replacement from him at cost, so it was only 300 out the door, but you do not want to go with a junkyard part, they are matched through the Vin and if you get the wrong one you'll end up having more problems.

 

[jroth142]

I finally got a chance to remove the bolt from the chasis and clean up the area and connection but unfortunatley it did not solve the problem. : (
I was looking at getting an EBCM rebuild off of ebay but I'm still not getting any kind of engine/abs light...Does these have any correlation to one another? Could the EBCM still be bad even though I haven't seen any engine lights?