Case Study Abs Brakes

[dolluper]

In the comes a 2012 Chevy Impala abs traction control stabilatrac control and brake assist warning lights on.. only happens when car comes to a stop at lights or stop signs....Codes are read CO 0040 ...which is loss of signal from right front speed sensor to ebcm.. Put scanner Foxwell NT 630 Pro on and watch speed sensors actions , they all pulled identical except when you applied the brake , right sensor jump to 15, 5om mph at a stop ...wiring or a sensor eh...So checks ohm sensor at wheel 1050 ohms within specs Ac scale spin wheel did not increase over 100 millavolt ac = bad wheel sensor ....if it did not ohm out at 1050 say less or indefinite it would be a wiring issue

 

[MTboatguy]

No matter what it says, I will bet you that sensor is bad, I had that happen on one of my Explorers and it drove me crazy until I said the hell with it and replaced the sensor!

 

[WIMUSKY]

My daughter had a bad wheel sensor that lit up the dash...... Sure was purty.......

 

[southkogs]

The hub on my Dodge is a non-serviceable assembly - and the ABS sensor is a part of the package. Currently, the hub is fine but the sensor is flaking out. So, I'm living with the same purty light on the dash ...

 

[gm280]

Could be the sensor is dirty and or the teeth the spin by it. They do get crud on them over the years, Just an idea.

 

[bruceb58]

The hub on my Dodge is a non-serviceable assembly - and the ABS sensor is a part of the package.

How am I not surprised!

On my Lexus, I screwed up and didn't disconnect my sensor when I replaced my control arms. Was a $150 mistake.

 

[WIMUSKY]

How am I not surprised!

On my Lexus, I screwed up and didn't disconnect my sensor when I replaced my control arms. Was a $150 mistake.

Our Charger was serviceable.........

 

[GA_Boater]

The hub on my Dodge is a non-serviceable assembly - and the ABS sensor is a part of the package. Currently, the hub is fine but the sensor is flaking out. So, I'm living with the same purty light on the dash ...

Our Charger was serviceable.........

The difference between a Benz Mopar and a Fiat Mopar? LOL

 

[km1125]

Can also indicate an issue with the bearing assembly itself. Not sure if it applies to the Impala, but sure was (and maybe still is) and issue with GM trucks from 99 till at least 07. Flaky ABS would be one of the first signs your bearings needed to be replaced.

 

[dolluper]

Impala inside bearing assembly, l did snip the wires at ebcm and ran a set of jumper wires with new connector right to wheel sensor (10 feet) just to rule out wiring harness. Ended up same results rf sensor goes 15 to 50 mph at stops when brake applied. Replaced hub assembly with built in sensor cleared codes and all is well for over 2000km. Next oil change will make sure

 

[jimr]

My regal has had an issue with the wires breaking right where they come out of the hub.

 

[strokendiesel002]

I have repaired several of the GM Trucks ABS issue, mentioned above... Never arrived a 2012 Impala, but in case it's a similar setup-

There is a machined surface atop The hub, that has 2 holes, one tapped (to secure the sensor) and the other goes clear through. Without fail, new sensors have been installed, factory or aftermarket, made no difference, the problem was still there. ABS kicking in when braking and speed under 8mph or so. Option A is to just replace the HUB assembly. Option B is to painstakingly inspect each child of the tone ring located in the hub using a pick and pen light (exercise in futility, but the comfort of knowing was worth it the first 2 trucks I did). Option C was to realize that the once nicely machined surface is now rusted, forcing the sensor just far enough away from the tone ring, that at low speeds, a fault was produced. Solution? Carefully remove sensor, redress machined surface with Emery cloth, light anti rust coating and reinstall sensor.

Hope that helps somehow, sorry for wasting your time if it doesn't

 

[flipbro]

Replace the wheel hub.

 

[gm280]

This is funny, because I just changed both front wheel hubs on my Blazer within the last week, and the new hubs came with new sensors. But the old sensors were working fine even though they were a little greasey and dirtied up. If your sensor wires are not broken or cut, maybe the problem isn't at the wheel sensors at all but at the ABS module itself.

Years ago my dad had ABS problems and it wasn't the wheel sensors. And since a new or even used ABS module was going to cost a small furtune, we decided to open up the ABS modlue to see what was inside. We found a cold solder joint and after resoldering it, everything worked perfectly again. Yes, that was mere luck, but I'll take it either way. But there isn't that much inside that ABS module. In fact it was shocking to see how little the number of parts were inside to cost so much. Way way over priced did come to mind. .JMHO

 

[bassman284]

Yeah, they're pricey. Kind of the beauty of safety things - you can charge whatever you want.

In about 2008, the ABS light came on in my 97 Jeep Grand Cherokee. It was late October and I decided to wait until there was some snow on the ground and see what happened. When we got some snow I took it out and tried it and, sure enough, the ABS didn't work at all. I had to modulate with my foot like in olden times. It was great. I was proud of my Jeep again. I took it to my mechanic in the spring for some other work and told him about the ABS. I said if it was just a wheel sensor I might fix it just to get the light shut off but since the ABS didn't work at all it was probably more than that.

When I picked it up he told me the module had gone bad and it would cost about $400 to replace it. He had a grin on his face like he knew what I was going to say. I said, "Hell Gary, 8 or 9 years ago I would have paid you $400 just to disable the damn thing."

 

[dolluper]

Yep l would say experienced good old drivers would be better off pulling the ABS fuses and running normally as used to instead of big brother screwing you up and potential putting you in a dangerous situation when the system screws up . I have seen brakes lock up ,power loss and other unsafe conditions when these idiot systems screw up. By the way they only introduced for idiots. Thank you big brother more to come for sure.BTU keep your battery charged on all your idiot devices or your up the creek without a paddle

 

[dolluper]

I must tell you the gm trucks are more forgiving they allow you to clean and replace the ABS sensor couple 8mil or 5/16 th's you pull it out the lmpala and other gm cars no option the whole bearing assembly has to be replaces just for a bad sensor

 

[HT32BSX115]

Yep l would say experienced good old drivers would be better off pulling the ABS fuses and running normally as used to instead of big brother screwing you up and potential putting you in a dangerous situation when the system screws up . By the way they only introduced for idiots.

I think I might disagree with that...... locked brakes are FAR more likely without ABS. Aircraft have had them for MUCH longer than cars and after they were introduced blown tires stopped happening even with "experienced good old pilots" Without ABS, you would be seeing airliners blowing tires and running off the runways everyday! ABS will always be better on cars and trucks than without.

 

[WIMUSKY]

I think I might disagree with that...... locked brakes are FAR more likely without ABS. Aircraft have had them for MUCH longer than cars and after they were introduced blown tires stopped happening even with "experienced good old pilots" Without ABS, you would be seeing airliners blowing tires and running off the runways everyday! ABS will always be better on cars and trucks than without.

Agree. Although, with all the traction systems and ABS, cars are no longer fun to drive in winter. I am glad, however, that my daughters car has 3 different systems... Makes a huge difference in the slop...... Brake pads wear quicker tho....

A lot of people have never driven a car w/o these systems. They would be scary to be around w/o them.......

 

[HT32BSX115]

Agree. Although, with all the traction systems and ABS, cars are no longer fun to drive in winter. I am glad, however, that my daughters car has 3 different systems... Makes a huge difference in the slop...... Brake pads wear quicker tho....

Yeah, traction control systems do use braking to reduce/eliminate wheel slippage when accelerating which would increase WEAR. (brake pads are pretty cheap though) an even more important function with front wheels (& ABS) is the ability to emergency brake and turn at the same time. If you lock front wheels during an emergency maneuver, or going around a tight turn, you can lose steering.......