OK, did some searching & can't seem to find a solution to my problem. on to my problem; replace the front brakes today. Replaced pads (ceramic) & rotors, old ones had already been machined once & were only .003" to .005" above the discard point. The work went without a problem ( should have been my first clue that something would go wrong! lol). when I went for a road test & stepped on the brakes I felt the ABS pulse 2 or 3 times then followd by a rapid clicking. this happed twice then the ABS light came on & brakes stopped great just no ABS function. So I pulled fuse #14 & tested the brakes & the stop on a dime! put the fuse back in & the same thing happened again! Any ideas on what could be wrong? All electric connections are good & fluid level is good. Thanks in advance for any help.

 

Possible wrong replacement rotors. Possible damage to the ABS front wheel sensors or their wiring.

 

as for the rotors I checked every measurement old to new side by side (I have calipers & mics & know how to use them lol) & because I don't trust the "kids" at the auto parts stores. as for the sensors the only time I touched them is when I had the rotor off I wiped off the exposed end with a clean cloth.

 

Correct me if I'm wrong but I believe that the ABS pulse teeth are cast into the backside of the rotor. I'm not sure of this because I haven't had the front brakes of a Ranger apart yet. I have heard of situations where aftermarket rotors have either the wrong number of teeth or the wrong tooth form. That's what I was suggesting.

 

I see, I checked every measurement exept size of sensor ring & number of teeth/slots. I will check that in the morning. Thanks, Bob.

 

Well rechecked every thing yesterday. size of ring & number of slots are the same, distance of sensor ring to back of rotor is the same. examined the wires to the sensors & can find no signs of damage. I can drive the truck for now with the fuse pulled thus diabling the ABS system. Looks like a trip to the dealer to see what's up. so much for trying to save a little money & do the brakes myself. :(

 

Turns out 1 of the replacement rotors had a bent sensor ring! these rings are pressed on to the backside of the hub. measuring from the back surface of the rotor to the sensor ring in several places (6) I came up with a difference of .075". (first check days ago was only in 1 place) On my old stock rotors all measurements were within .010". Checked the other replacement rotor all within .010". Went back to the parts store, they had 2 in stock, measured both of them 1-all within .020" the other all within .010", took the better of the 2 put it on, brakes work perfectly. So heads up to anyone replacing rotors, check the all the measurments! especially to the sensor ring! I used a depth mic & a ground parallel (to span the rotor) Also you could use a dial caliper & a parallel. Glad to have the brakes working properly again! Thanks again Bob, you pointed me in the right direction!

 

Glad you got it nailed. Good info for the rest of us.