Hi all,

I have a 2003 Ford Ranger 3.0 V6 2wd with 68,000 miles on it.

Just some background: I bought the truck to fix it up. It was in an accident, apparently it hit a stone wall on the drivers side. I replaced some body parts on it and did a little straightening of the core support. Apparently the guy I bought it from started fixing it. Not sure what exactly he did. Something with the A-arm area I think, I know he replaced the brake caliper with an aftermarket bosch and possibly something in the hub. Again not quite sure.

Now for the problem: The abs light is on... The code it throws is a C1939 (brake pressure switch circuit failure or something like that). I have replaced the brake pressure switch at the master cylinder. And I still have the problem. The fuse for it is good and I tested the switch (which worked). A friend of mine tested the wires to the switch and I think he said it was fine.

Something I noticed is when I unplug the brake pressure switch the abs light won't come on but there is a pulsating in the petal (abs turning on?). When driving at 15-20mph (maybe over?) and you slam the brakes on it will slow down some then the abs turns on when you reach a relatively slow speed (with no loss of traction to the tires as far as I can tell). The rear brake pads are not all that good by the way...

Another thing I noticed: With the brake pressure switch plugged in, and the scanner tool plugged in I did the following. With the code cleared I would drive the truck at slow speeds (under 10 mph) no light and I think no petal pulsating. Once I drive over 10 mph (the speedometer first starts registering) the abs light turns on even without the brake pedal being touched. And the pulsating happens when coming to a stop.
This also happens when going in reverse (with the same scenarios) .

It almost seems that it could be one of the speed senors but why the code C1939? Does this problem have anything to do with the speedometer starting to register/ abs sensing? Is there any way the brake pressure switch would have anything to do with the abs turning on? As far as I know that switch is mainly for the cruse control to shut off if the petal is pressed.

Any help would be much appreciated! Thanks!!!