ABS kicking in, parking lot speed

[SawyerRanger]

My ABS system has been kicking in when I am making a sharp turn at slow speeds and braking. I've only noticed it when parking. It doesn't seem like a major problem but I have had some close calls because I don't expect it. The ABS works just fine other than this. Any help would be appreciated!

 

[Sasquatch_Ryda]

One of the front speed sensors or wheel bearing is faulty. Its easy to figure out which one is the problem with a scan tool that allows you to monitor the ABS PIDS...the one that drops off or flat lines is the one at fault.

 

[SawyerRanger]

How many speed sensors does this truck have! lol. Just had to replace the one on the differential for my speedometer. So is this the part that I would need? (Pending further investigation)

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Sensor---ABS-BWD_20970239-P_1061_R|GRPABSPAMS_521676614___

I'm leaning towards the right side, since it "feels" as though its the right side, and it happens more when it's at full lock to the right.

 

[Sasquatch_Ryda]

You won't be able to 'feel' which side is causing the issue.

You have 3 sensors.....one on each front wheel bearing hub assembly and one in the rear diff.

 

[SawyerRanger]

Ok excellent, I'll have to get myself a scan tool and figure this out.



EDIT: I'm betting the ABS PIDS scanning function is probably on one of the more expensive scan tools, yeah?

 

[Sasquatch_Ryda]

Well as I work for a ford dealership....I only use our scan tool, so you're on your own there.

 

[SawyerRanger]

Damn, you get all the nice toys to play with, haha. I appreciate your help in pointing me in the right direction, thanks a ton

 

[kamps989]

I'm having the exact same issue, does anyone have experience with replacing the sensor? is it fairly straight forward with standard tools?

 

[satan]

At parking lot speeds in turns - tire diameter also comes into play - The ABS for your ride does not adequately consider the inertial vector, but instead approximates it all by comparing wheel speeds.

Something as simple as air presures or unequal tire wear could adversly influence the calculations at low-spped and high-rate-of-vector-change.

It'd never hurt to check tire pressures or rotate your tires as you diagnose the repeatability of this symptom. See if your symptom repeates for both left and right turns...

Watching PIDs with a scanner is handy (ABS Scan tools are kinda not "off-the-shelf" for some of us) -- a multi-trace portable o-scope can watch the wheel sensor waveforms directly and offer similar (though not as exact) results.

Replacement is not tough - but that also depends on how dirty/corroded the sensors are.

 

[rkd68]

My ABS system has been kicking in when I am making a sharp turn at slow speeds and braking. I've only noticed it when parking. It doesn't seem like a major problem but I have had some close calls because I don't expect it. The ABS works just fine other than this. Any help would be appreciated!

at first, my ranger did the same with the abs actuating with only left hand turns, but over a course of the summer, now the abs actuates pretty much forward or reverse and UNDER 8 mph. ive checked the rear and right side abs sensor readings with brand new, look ok.

also have pulled fuse #14 but that also disables my speedo...bad idea!

im looking at replacing both front wheel hubs, which brings me to my question......anyone know a good brand name wheel hub that wont drain my bank account as a DIY'er???

 

[rkd68]

I'm having the exact same issue, does anyone have experience with replacing the sensor? is it fairly straight forward with standard tools?

the rear was easy to get at and remove, careful not to knock any dirt in when you do have that one pulled. the fronts are covered by the dust shield so i had to remove the tire and everything else to get at it.

the rear is just the sensor, cable plugs directly in. fronts have the cable attached and connect just behind the bumper.