Hi everyone,

I have a 93 Ford F250 4x4 that I purchased recently. I just completed putting new brakes all the way around and thought I would flush the old brake fluid out and replace with brand new fluid. thought I was doing a good thing.

Now, my brake light (red light) and my ABS (RABS) light are on. Both are solid not blinking. I double checked this weekend that the lines were bled of air and i'm getting nice clear fluid at all valves. (pattern: back right, back left, front right, front left)

so now i'm stuck. the brakes work but I cant get the dang lights off.

Any tips on what I need to look for?

Thanks in advance.

Nathan

 

Looks like you forgot about the RABS hydraulic module located on the driver side frame rail when you were bleeding the brakes.

Great troubleshooting info here:RABS Troubleshooting courtesy of Steve83

 

oh... I didn't realize that had a bleeder valve on it. i'll check that out.

After I bleed the RABS module, I would assume I have bleed the back brakes again, right?

Thanks for the RABS link to btw.

 

You should be good to just bleed the RABS module since you already did the rears. This may not help you with the Yellow and Red warning lights, but heading off another issue with poor brake performance.

The Red brake is typically caused by low brake fluid and/or the fluid level float gets stuck in the down position. With it on you will not be able to pull the RABS code(s) that are triggering the Yellow light.

Welcome to FTE..

 

I have bled the RABS with no air coming out. I have also bled the brakes from the master cylinder. Still the ABS and Red Brake light remain on.

all this because I decided to be a good boy and flush my brake system and put in new fluid. lol

anyone have any ideas?

 

I remember reading someplace on this forum that you actually have to flush the brakes in a particular order for RABS to work right and lights to go off.

 

As mentioned, check the fluid level float inside the brake fluid reservoir. Give it a few taps with the handle of a screwdriver and see if it comes good.

 

there is also a switch on top of the rear axle. it will be the switch on the axle with wires going to it. obviously.

One time my ABS light kept coming off/on, I removed and cleaned the switch and reinstalled it, and my ABS light went off. luckily I didnt have to buy the switch.

the switch had a bunch of gunk on it,

also your master cylinder could be bad, or you have a leaking brake line somewhere, thats the only other possible things that it could be. or the light wouldnt be on.

 

you're suppose to bleed brakes in this order:

rear passenger side, rear driver side,

front passenger side, front drivers side,

then the rabs,

at least thats how I did it when I changed my brake lines.

 

This is good food for thought. Just replaced front rotors studs and nuts , calipers, pads hoses. Master cyclinder and power booster. (230K miles) after calipers would not release. Abs light on now and not before. Yes I knew about unit on frame and bled it. Will check the switch on diff. tonight when I get home. Thanks.

 

I disagree and so does the Ford service manual:

1.rear passenger side
2. rear driver side
3. RABS hydraulic module
4. Front passenger side
5. Front driver side

 

There is no switch on top of the rear axle. It's a vehicle Speed Sensor (VSS). It's a combined function on a 1993 F-series truck. The raw signal is for the RABS system. The buffered signal is used for the speedometer, computer (PCM), and the cruise control.

 

with the exception of the RABS module, thats word for word what I typed.....

 

if you read the manual that part on the axle is on of the possible causes of the ABS light coming on. no matter what you're calling it.

also low brake fluid, faulty m.c., leaking brake line, brake pads/drums......

 

No, you stated a different order.