99 blazer abs problem

[jmalecki]

99 blazer when stopping gets to about 10 mph and the abs kicks in and truck dives right any ideas? has new right side front bearing and left was replaced about a year ago.

[danielsatur]

The ABS system isn't going to work, you should still have old school breaks.
Is there any Alarms? VSS

[Airjer_]

These are very easy to diagnose with a scan tool that shows live ABS data. You will likely see one of the front speed sensors dropping out at low speed which is a pretty common problem with GM vehicles. Some things you can check are makins sure the harness is in good shap, Make sure the connector is solid and clean, and if the ABS sensors bolts to the bearing make sure there isn't a build up pof rust under the sensor.

If I had to guess I would say the Left front is the one giving you the problems.

[danielsatur]

90% of breaking is on the front breaks + all the heat!

[MT-2500]

Originally Posted by danielsatur

The ABS system isn't going to work, you should still have old school breaks.
Is there any Alarms? VSS

And when you hit a patch of ice or slick spot in a sharp curve old school brakes will put you in the ditch might fast.:sarcasm1:

[danielsatur]

ABS is probably the best safety feature in years, I wouldn't go without it, however
there's a bunch of cars registered in this country without it.

1.4 million Americans who sustin traumatic brian injuries each year, 1/2 were involved in an
automoble.

Wow - I'am working on six diffrent project + patents!

[b1lk1]

I'd say 2 different issues.

1. ABS kicking on at 10mph is something to do with the wheel speed sensors. As said, common issue and a decent ABS scanner will show you which one. My truck did this until I changed the bad sensor BUT it didn't pull when it happened.

2. Stuck caliper is probably causing pull or even a bad wheel bearing.

As for the ABS/no ABS argument, I am on the fence. My wife's 02 Mustang with no ABS stops better in the snow/ice than my 99 Jimmy with ABS.

[goser]

There is a GM TSB about this which I found on another blazer forum. Basically rust forms arount the wheel speed sensor which increases the gap in the sensor and causes low speed ABS activation. Can be repaired by removing sensor and cleaning or by replacing wheel hub. I unplugged my wheel speed sensor when this started happening so I wouldn't very slowly drive into someone...could be very dangerous if not fixed...

[old_master]

This TSB might help:

#02-05-25-006B: Antilock Brake (ABS) Activation at Low Speeds (Clean Wheel Speed Sensor Mounting Surface) - (Jan 5, 2006)


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Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting Surface)


Models: 1999-2000 Cadillac Escalade
1995-1999 Chevrolet Silverado (Old Style)
1995-2000 Chevrolet Suburban, Tahoe (Old Style)
1995-2003 Chevrolet Astro Van, Blazer, S10
1995-1999 GMC Sierra (Old Style)
1995-2000 GMC Yukon, Yukon XL (Old Style)
1995-2001 GMC Envoy, Jimmy
1995-2003 GMC Safari Van, Sonoma
1995-2001 Oldsmobile Bravada





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This bulletin is being revised to update the correction and warranty information. Please discard Corporate Bulletin Number 02-05-25-006A (Section 05 -- Brakes).


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Condition

Some customers

may comment on ABS activation at low speeds, usually below 8 km/h (5 mph). Upon investigation, the technician will find no DTCs set.


Cause

The cause of this condition may be an increased air gap between the wheel speed sensor and the hub reluctor ring due to rust and debris built up on the sensor mounting surface.


Correction

Measure AC voltage and clean wheel speed sensor mounting surfaces.

Raise the vehicle on a hoist.
Disconnect both the front wheel speed sensor harness connectors .
Place a DVM across the terminals of each sensor connector.
Rotate the wheel with hand speed and measure the ACmV's. The reading should be at least 350 ACmV's.
If the reading is between 200 and 350 ACmV's, remove the wheel, caliper and rotor in order to gain access to the speed sensor.
Remove the wheel speed sensor and plug the hole to prevent debris from falling into the hub during service.
Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery cloth, ScotchBriteTM, or other suitable material. Be sure to thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
Check the sensor head to determine if it has been warped/distorted due to the corrosion build up or other causes. Check the mounting surface on the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3) positions/directions. If the sensor head is distorted, replace the sensor.
Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant, P/N 89022217 (Canadian P/N 89022218).
When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing grease to the hub surface and sensor O-ring prior to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (Canadian P/N 993037).
Install either the original sensor or a new one in the hub and secure the sensor. Ensure that the sensor is seated flush against the hub.
Install the rotor, the caliper and the wheel.
Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel by hand. The voltage should now read at least 350 ACmV's.

[serge_saati]

The best and simpler thing is to disable the ABS seriously
Airjer will beat me

[MT-2500]

Disabling a saftey device is very illegal and can cost people there life.

[b1lk1]

Besides that, these things hare all over the road as it is and they truly require properly functioning ABS.

[Cobber]

Is that TSB like a recall? Do the dealers fix it for free?

[Airjer_]

TSB's are Technical Service Bulletins. They are recognized frequent issues that a resolution has been found for. They are assigned a number by the manufacturer and released to there dealer technicians and ultimately us. There can be hundreds of TSB's for a particular model. They are meant to help technicians diagnose and repair frequent issues faster and more accurately. They are not done for free unless your vehicle is still under the manufacturers warranty coverage.

Recalls generally involve a safety issue. F150's starting on fire, Toyota's accelerating out of control, Chrysler rear windshield wiper grounds causing air bag deployment, Explorer's rolling because of tire failures, etc.

[Cobber]

anyone have prices for these sensors?