1998 ford F150 abs light stays on/master cylinder is full of fluid

ABS lights are usually triggered by a sensor, not a master cylinder.

Check the fluid level in the master cylinder and make sure its full.They usally have a sensor to let you know when the fluid is to low.

I believe the fluid/brake light is only intended to indicate the parking brake is on or the master cylinder reservoir is low . ?????

Wrong !!!!!! problem's with ABS can also turn on that light as well ! Take it a have codes checked .

your abs light is on also and your master cylinder is shot buy a new master and reset your abs plunger to the neutral position

Ford uses a sensor for brake fluid, to test disconnect from Master Cylinder and connect the leads together. If light goes out, replace the sensor.

It could be the ABS unit it's self that is at fault

ABS light being on could be a bad sensor or broken wire to the sensors. ABS is on the front brakes, check the front wheels inside for wiring going up to the main ABS ecu mounted at the master cylinder. Check the wires from at the bearing assy. then follow up to the ABS ECU or the brain, for any cuts or nicks. You can have a bad wheel sensor you check these with a volt/ohm meter, Find the plug at the wheel and unplug it ck for ohms should read like .018 ohms. If you raise the wheel and spin it you can then read volts, depends on how fast you spin the wheel you can get 2-3 volts. .

thats odd. Adding brake fluid shouldn't have kicked on the ABS light..

Low brake fluid would cause your RED parking brake light to come on not the orange ABS light (unless thats what you mean. if thats the case its normal for that light to come on with low fluid. in this case check the brake lines starting to the master cylinder and the components at the wheels to make sure there is no leaks if you go HERE complained about your situation and also noticed a leak on the bottom of the master cylinder (hazardous in more than 1 way) )

not sure of the component locations under the hood of the windstar but check to see if you were bumping wires on the ABS control module when you were putting brake fluid in. may be a loose connection that jiggles loose when you drive.

otherwise it might need a new ABS control module or maybe moisture in one of the components.

Bleed your brakes by filling the master cylinder, then bleed at the wheels in the following order: right rear, left rear, right front and left front, ensure the master stays full and then test to ensure all air is out

NO CK FOR WIRES BROKEN TO ABS SENSOR ON TOP OF THE REAR TWO WIRE TERN. & CK SENSOR IN REAR WITH OM METER