I had to get on my brakes hard today, but not as hard as i have before, the front ones did not even lock up. Now the abs and brake light is on and i was wondering how to check it. I know you have to ground a connector and then the light flashesbut i dont know what one to ground? The lights also go out when i press the brakes down, and it is not leaking and is full of fluid, but i can press the pedal to the floor? I has rear abs too.

 

This happend to me once too. For mine it was the switch that senses if there is a pressure diffience inbetween the front and the back, its located on the brake proporshing valve. My switch got stuck I just took it off and cleand it up that took care of it. It also sounds like your master cylender is going out. I have replaced it at the same time the swtich failed. But I did find the wire that needs to be grownded. It is the passanger side under the dash. a black wire with a white stripe. I belive mine was taped up onto the wireing harness. I did get it to flash but I never found what the ABS codes. If anyone knows them post them so we all can find out. (I put that ABS lable on it, yours wont have it.) ( the switch is in the red circle.)

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OK...Lets see if I can help. When you got on the brakes hard, if they've locked up in the past there was something wrong. They are not supposed to lock-up unless of course you are in loose gravel or snow etc. Hence the name Anti-lock Brake System. I'm not tryin' to be snobby (as my wife just told me) just stating the fact. Reason being if the front locks up on heavy braking you cannot steer the truck while stopping. Now that we have that cleared up let's move on. When the ABS light came on in my truck it was because the brake fluid level was very low in the master cylinder. That's not to say that is the only reason it comes on but based on what you described I'm guessing this may be the case. You said that the master cylinder is full and you aren't leaking anywhere. There are several places you can look for leaks that aren't apparent without disassembling something. The first would be the rear wheel cylinders (if equipped) the other is the power brake booster. That's that flying saucer looking thing behind the master cylinder . You have to pull the master cylinder off the booster. If fluid pours out as you detach it...there's your leak. Another possibility is that the calipers froze in the out or engaged position. In other words your brake pedal comes back out but the calipers did not disengage the brake pads fully thus when you press the brake pedal it goes to the floor, which might also explain why you see no leak. I think but not entirely sure that the ABS light is also linked to the brake proportioning valve. That's the gizmo that turns your brake light on when the fluid is low. When the valve goes too far in one direction it triggers the light. I hope this at least gives you a starting place. Unfortunately I am not aware of a terminal that needs to be grounded. I've only had my 95 Dakota for two years this November but I've been a mechanic both professional and backyard for too many years to count. Really hard keeping up with all the new stuff...guess that's why I got into computers...hehe

PS If I totally bored you and was way off the mark..let me know too cause I tend to get long winded when I try to help (my wife just told me that too).

 

I think Bad96_3.9has rear wheel only abs. So the fronts can lock up. If he has 4 wheel abs, the fronts will not. I think thats what he ment by " I has rear abs ". Rear was standard after 93. 4 wheel abs was optional.

 

Thanks for clearing that up crazy. Iwas thinking the master cylinder because they have gotten spongy, and no air is in them. I have fairly new wheel cylinders and the calipers are not sticking. I will be sure to check that sensor, and i should be able to get the codes and post them hopefully. and if you would have really read the first post that is why i said the FRONT one did not even lock up, cuz i have rear abs. but thanks for all the help anyways.

 

See you learn something new every day. I took this to mean that you have rear ABS also. I wasn't aware that they made rear ABS only. Like I said, I'm still a newb with these here Mopars. I promise to read more carefully next time.

 

well it turns out after about an hour of looking i figured out i dont have one of those wires, because mine is obd2, lol. The black and white wire runs to the data link and you ground it there. i could not get it to work still so i dug out the old service manual and figured it out following some tests, and it is the same part, the diffrential pressure switch. no parts stores have them so i will try the dealer tomorrow, cuz mine is stuck and i cant get it to move. but thanks for the help and the idea about the switch. and pashadowops, i am pretty new to the whole mopar thing too, so i know how it goes!

 

No problem! We Dakotas gota stick together!