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Speed sensor to EBCM harness?.looking for p/n???

Mike2005

Full Member
Joined
Mar 9, 2014
Messages
53
On another post I'm being lead to the speed sensor as a potential problem with my brake lights/warnings coming on.

Feeling from the forum it is not likely the EBCM itself but the referenced harness.  My shop (after $1100 and the lights still coming on) wants to now change the EBCM - but before I do that, I'd like to investigate this harness thing.

Can anyone give me a p/n for the harness (right and left side) and give me an idea how hard this is to change?
Thanks

Mike
 
I have never heard of such a harness.  :dunno:
 
This is from a member named CHIEF:  I cut/pasted: 


"It is almost certainly not the ECBM. There is a wiring harness that leads from the wheel to the brains of your Avalanche. These harnesses can corrode over time and fail, or the where they plug into the hub can get filled up with dirt, gunk, and it can eventually crack the plug. The signal from the wheel speed sensor is sent on this harness to your vehicle.

Failures on GM vehicles are very very common. Mechanics who can't fix this problem are also, sadly, very common. The part is dirt cheap, and the labor to install it properly is less than an hour. Your better off just doing both front ones. Your symptoms fit the issue perfectly.

Basically you're getting an intermittent short, or loss of signal, that has the system go, "AHHHHHHHH, no ABS!!!" or, "Someone just slammed on the brakes so hard it screwed up the system - voltage signal out of spec! Voltage signal out of spec!"

The light will come on for no reason, go off for no reason, and can't be repro in a shop. A failure will appear to be a bad bearing by the code (where the speed sensor lives) when really the bearing and sensor are fine, the harness is bad.

Someone else can chime in, but my recommendation is to find a different shop, and basically just tell them, your speed sensor front harness is bad and you want both front ones replaced - end of discussion. I'm going to bet 98% chance your problem will be gone."
 
No such harness, can you tell us your problem again.
 
Wheel speed sensor issues are a problem and are reasonably cheap and easy to fix..

The ABS control module can also have bad solder joints on the circuit board too. Both are somewhat reasonably easy fixes and can cause ABS alarms and some other traction control related stuff if your truck came so equipped.

But hard to help you if you don't share the symptoms.

Please see the following thread:
http://www.chevyavalanchefanclub.com/cafcna/index.php/topic,134662.0.html
 
Hi guys:  On May 11 I posted this in another post in the brake section.  It was there that I got lead to this harness suggestion:

"2005 LT 2WD.  190,000.

Recent "service brake system" message, ABS and Brake lights on.  Just spontaneous.  Sometimes when driving it would just go away. Turning the AV off didn't always mean it came back on.  Last week it got real annoying - on more than off.  So I took it in - reputable shop open since 1948.  Oh, an occasional smell of burning rubber, but couldn't really tell where it was coming from. 

Bad right front bearing - said that might cause the ABS to come on.  I had the left replaced about 3 years ago and don't remember an ABS issue?
Rear axle leaking - onto something related to the  parking brake - resealed the axle. 
Cost a pretty penny to fix. Over a grand.  Please don't tell me I was ripped...

10 miles into driving-all bells and whistles come back on.  I take it back. 

After having it all day, I get a call at the end of the day - technician cannot get warning lights to come on.
They found a service bulletin about the ground - cleaned that.  Otherwise, nothing.  So, I'm told "It could be, might be the EBCM."  But, it'd have to be a "chance" change out since they can't get a code or anything to get an idea.   Over $800 to change "if I wanted to."   

Ideas?  EBCM?    If it is the EBCM, I see on a couple of posts in the forum it is something accessible.  Some of you have seen my posts, I'm not the mechanic like many of you but I am willing to do some stuff if I can get some direction.

Thanks..

Mike"

I hope this helps, thanks again for all the advice.  The bells and whistles continue to go off and on for no reason.  The brakes seem to be working?.
 
Great Post and my Kudos to you for sticking with it. You've had your rig longer than 3 of mine and more miles combined with them since 2003 so I have not hit the wall as many others have with longevity of ownership or buying someone else's mess.

I have no information provide, but the part about the wheel bearing possibly whacking out the ABS sensors is an enlightenment for sensitivity to me. I'm not certain that is a good thing or not.

As for trying to avoid going in the ECBM direction, I fully understand, yet you have just about resolved most of the probable issues it could be except for that. Others will chime in with stuff that I dare not even bring up, but if you have access to a 2nd hand ECBM and your Gear head Mechanic is wiling to go an extra step to eliminate all possibilities, I'd really consider taking that direction.

What is the worse that could happen besides the extra dollars change a challenging rabbit?  :E:

Again, thanks for keeping us up to date and for staying with it.  :B:
 
Try these guys.  I replaced the EBCM in my 03 with a rebuild from them at least a couple of years ago and is still working fine.  Price wasn't too bad either.

https://modulemaster.com/
 
Check for bad wheel bearing as sensor in hub and can't be changed out alone
Hub is pricy but easy fix for abs light on
As bearing usually inside fail it allows grease that left to cover sensor so really abs light is a bad wheel bearing light lol
Mine a 05
Ps core charge for old hub was 100$ keep recept
 
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