ABS problem

Brakes started acting funny after I had the pads and rotors changed. Van will stop fine, but in the last 10 to 15 feet of a stop it feels like the ABS is pulsing for no reason. (feels like the pads have oil on them and the van is pushing through the stop, definite noise heard too.) Checked and cleaned rotrs and they are fine. Also is especially bad when the van is turning into a parking space and the brakes are hit, there is a loud noise, the best way to describe it is it sounds like one of those old fashioned spring door stops that you used to flick as a kid.

Is it possible that a ABS sensor is out of whack? Is that easy to adjust and if so how?

Any help would be great.

Thanks allot.

I too am having similar problems with ABS brakes pulsating and a loud noise when slowing down to a stop. The noise is like a springing sound and the pedal seems to harden.
Would like to resolve problem if possible.
Any kind of help would be appreciated.
Thanks Bibi

You should be able to temporailly disable the ABS via the fuse to see if that eliminates the problems and verify that it is in fact the ABS that is causing the problems

I also have a very similar problem with my 1995 Windstar. At the end of a stop the ABS motor comes on and dumps the pressure in the brake petal. I never really fear that the car won't stop but it is a little scary. I did remove the fuse and the problem goes away. Doesn't really solve the problem and now there are two lights on, the ABS and Brake light. I'm thinking it's a sensor on one of the wheels but really don't know for sure. I plan to have a friend put a computer on the car and see if there are any error code that would indicate an exact area to look.
Any help with this problem would be appreciated.

Dave

You will get both a brake light and ABS light if your fluid level is low. By low I mean as little as a quarter inch below the full-line.

If you have done any kind of brake work, you need to bleed the hydralic system. Air bubbles in the hydraulic lines and other components will cause problems like squishy brakes, for instance. This is because air readily compresses where hydraulic fluid resists compression, which is how it powers the system.

I think that in my case something more than low fluid or air in the lines is causing my problem. As mentioned above, the ABS activates everytime I make a stop. You know, the buzzing sound and the release of the brake petal preasure. All is normal when the fuse is removed. I had the fuse out for about 2 months and just put in back in a week ago, so that I can get a reading on the error codes via a friend who has a nice and expensive reader. But after a week of driving the light still hasn't come back on, even though the ABS is activating at the end of each stop. I thought I read somewhere that it takes 3 warmup and cooling down cycle with a recurring problem before the engine light will come on. I any case I am waiting for the light to come on again so my friend can read it. My problem sounds very simular to the first two entries mentioned below. Any additional help would be appriciated!

I think that in my case something more than low fluid or air in the lines is causing my problem. As mentioned above, the ABS activates everytime I make a stop. You know, the buzzing sound and the release of the brake petal preasure. All is normal when the fuse is removed. I had the fuse out for about 2 months and just put in back in a week ago, so that I can get a reading on the error codes via a friend who has a nice and expensive reader. But after a week of driving the light still hasn't come back on, even though the ABS is activating at the end of each stop. I thought I read somewhere that it takes 3 warmup and cooling down cycle with a recurring problem before the engine light will come on. I any case I am waiting for the light to come on again so my friend can read it. My problem sounds very simular to the first two entries mentioned below. Any additional help would be appriciated!

I agree, you seem to have a more serious problem.

From the Ford service manual '97 Windstar--

Anti-lock brake system (ABS) operates as follows:

When the brakes are applied, fluid is forced from the brake master cylinder outlet ports to the brake pressure control valve block inlet ports. This pressure is transmitted through four normally open solenoid valves contained inside the hydraulic unit, then through the outlet ports of the hydraulic unit to each wheel.

The primary (rear) circuit of the brake master cylinder feeds the RH front and LH rear brakes.

The secondary (front) circuit of the brake master cylinder feeds the LH front and RH rear brakes.

If the anti-lock brake module senses that a wheel is about to lock, based on brake anti-lock sensor data, it pulses the normally open solenoid valve closed, for that circuit. This prevents any more fluid from entering that circuit.

The anti-lock brake module then looks at the brake anti-lock sensor signal from the affected wheel again.

If that wheel is still decelerating, it opens the normally closed solenoid valve for that circuit. This dumps any pressure that is trapped between the normally open valve and the brake back to the brake master cylinder reservoir (2K478).

Once the affected wheel returns to speed, the anti-lock brake module returns the valves to their normal condition allowing fluid flow to the affected brake.

The anti-lock brake module monitors the electro-mechanical components of the system.

Malfunction of the anti-lock brake system will cause the anti-lock brake module to shut off or inhibit the system. However, normal power assisted braking remains.

Malfunctions are indicated by a warning indicator in the instrument cluster (10849).

Loss of hydraulic fluid in the brake master cylinder reservoir will disable the anti-lock brake system.

The 4-wheel anti-lock brake system is self-monitoring. When the ignition switch is placed in the RUN position, the anti-lock brake module will perform a preliminary on-board diagnostic check on the anti-lock brake electrical system indicated by a two-second illumination of the amber anti-lock indicator in the instrument cluster

During vehicle operation, including normal and anti-lock braking, the anti-lock brake module monitors all electrical anti-lock functions and some hydraulic operations.

In most malfunctions of the anti-lock brake system, the amber anti-lock brake indicator will be illuminated.

The sequence of illumination for these warning indicators combined with the symptoms can determine the appropriate diagnostic tests to perform.
Most malfunctions are recorded as a diagnostic trouble code (DTC) in the anti-lock brake module keep alive random access memory and assist in pinpointing the component needing service.

From the 97 Windstar Maintenance Manual:

Anti-Lock Brake System Bleeding

NOTE: Add Ford High Performance DOT 3 Brake Fluid C6AZ-19542-AA or equivalent DOT 3 fluid meeting Ford specification ESA-M6C25-A as necessary throughout this procedure.



Connect a clear waste line to the LH front bleeder screw.

Open the LH front bleeder screw.

NOTE: One cycle of the brake pedal is from the full upright position of the pedal, to full extension of the brake pedal, to the full upright position.



With the bleeder screw open, cycle the brake pedal 25-30 times or until no more air is seen in the waste line.

Close the LH front bleeder screw.

Disconnect the waste line from the LH front bleeder screw.

Repeat Steps 2 through 6 for the front right brake, rear left and rear right brakes.

NOTE: The engine must be running to provide battery positive voltage (B+) to the ABS module.



Start the engine.

Depress the brake pedal to half of the full extension position.

NOTE: Performing the NGS program routine drives entrapped air from the otherwise inaccessible lower sections of the ABS valve into the upper sections (accessible by bleeding at the brakes). Subsequent bleeding removes the air from the system.



Perform NGS program procedure for ABS service bleed.

Attach the Rotunda New Generation Star (NGS) Tester 007-00500 according to manufacturer's instructions and follow the menus and prompts.
From the "DDS Functions" menu, chose "4-WABS."
From the 4-WABS menu, choose "Function Tests."
From the Function Test menu, choose "Bleed Procedure" and follow the prompts.
NOTE: One conventional pressure bleed cycle consists of advancing the brake pedal to its extended position, opening the bleeder screw, allowing fluid to be released into the waste containers, closing the wheel cylinder bleeder screw (2208) and releasing the brake pedal to its full upright position.



Perform a minimum of 7 conventional pressure bleed cycles on the LH and RH front brakes.

Repeat Steps 9 through 13 two times. However, on the last bleed cycle, make sure to bleed the rear brakes to ensure that all air is removed.

So you could have bubbles in the ABS causing problems...

Thanks Dngrsone, That's good information. I'm still a little puzzled why the ABS light hasn't come back on yet since I put the fuse back in. As soon as it does, I'm going to run over to my friends place and have him read it. I wonder if it could be dirty sensors or the gears. I have read some of the other threads on brakes problems and a few of them talk about the cleaning of these. I have done all the brake work on this vehicle myself and really haven't had the system open, just changed the pads, shoes and rotors occasionally. So I really done think it's air in the lines. The ABS pulses at every stop so it seem that it could be one of the sensors or maybe mud or something on the gears. I really won't have time to even look at it until next week sometime. When I figure it out I will let you all know what it was. Boy I'm really assuming a lot here aren't I. That is that I'm going to get fixed.

Thanks Dngrsone, That's good information. I'm still a little puzzled why the ABS light hasn't come back on yet since I put the fuse back in. As soon as it does, I'm going to run over to my friends place and have him read it. I wonder if it could be dirty sensors or the gears. I have read some of the other threads on brakes problems and a few of them talk about the cleaning of these. I have done all the brake work on this vehicle myself and really haven't had the system open, just changed the pads, shoes and rotors occasionally. So I really done think it's air in the lines. The ABS pulses at every stop so it seem that it could be one of the sensors or maybe mud or something on the gears. I really won't have time to even look at it until next week sometime. When I figure it out I will let you all know what it was. Boy I'm really assuming a lot here aren't I. That is that I'm going to get fixed.

I assume that it's still misbehaving, just not flagging a code? The Ford computers are weird sometimes... I spent a week trying to figure out why I had a bad idle and it wasn't until I actually took the damn van out on a drive that the stoopid light came on.

Yeah, it sounds like maybe you have a sensor going flaky or something... the only reason I was suspecting air in your case is the pressure drop you get when the ABS engages.

I have the same confidence problem... I was wondering if I would ever get the van running after tearing it down like I did :smile:

It's common for a wheel sensor to lose its sensitivity at low speeds, which will cause unwarranted ABS activity and/or set an ABS code. To find the faulty one, use a scan tool that has module data display capability. Select the ABS module and input data from all the sensors. Drive the van slowly and watch the voltage from each sensor. The sensor that drops off before the others is the faulty one. Frequently, the back sensors get rusty and sometimes the tone rings on the front CV joints break. I've managed to "repair" rusty rear sensors by cleaning off the rust scale, but dealers and repair shops will always replace the sensors to make a repair they can guarantee.

I too have not been able to get the ABS light to come on.

Which fuse is the ABS fuse, I would like to remove it and see if it stops making noise.

I just had this checked out on my van and the mechanic told me it way the abs relay. he checked it on the computer that you plug into the car. have not bought the relay yet and don't know where it is located on the car. that is what i need help with.

Fuse L provides the power to the ABS Electronic control module.

Mauby, I don't see any relays for the ABS in my schematic. The OBD II code 1185 is called ABS Power Relay Fault. The pinpoint tests for this fault have you look for low voltage coming from fuse L to the Control module. If the voltage getting to the control module is good, then the callout is the control module itself.

Ok i'm a mechanic that had the pleasure to work on a 95 windstar with a ABS problem . The problem was the same one that you are all describing.Before the problem started she had both rear brake lines replaced.I don't see the conection but who knows, I worked on the damn thing for four days before i got it figured out. After the third day i told my boss to take it to the dealership. They could'nt figure it out either. So we got the car back to our shop, I knew that the problem had to be one of the sensors even though they all tested ok.The problem turn out to be a weak signal in the back sensors .Don't know which of the two because they both had the same problem . The problem was RUST! There was rust building up underneath the bracket that holds them in place .It was causing the sensor to move away from the the ABS ring . That is what was causing the weak signal & the ABS to activate .It activates because it thinks that one of wheels in the back is locking up even though it is not. What i did to fix the problem was i took the sensor out VERY CAREFULLY . I cleaned the rust from the plate and i had to bend the sensor straight. DO NOT bend it too close to the ring or you will hit it . You want to be about two centimeters away from it . For a more acurate way of doing it use a ohm meter . Bend it until you get the same reading from both of them . The reading that i got was( 2.69ohm ) Once again be very carefull . I don't know if this will fix all the ABS problems on this forum But it is what fixed my ABS problem And from what I have read this is the only one that has worked. Good luck to all of you And let me know if it helps you guys.

Sounds like a can of gas and a match would work easier