99 Dodge Ram 3500 4x4 Dump Diesel ABS light 4WAL
I have had this truck since '99, bought it new. It only has 15,548 miles on it and all of a sudden ABS light kicks on. This truck does not have Rear Anti lock breaks just front. Can not reset light but code came up 4WAL. Not sure what to do now. Would appreciate any advice with this situation. Thanks so much.
4WAL means 4 wheel anti lock, which means you have 4 wheel abs, the rear doesnt use a speed sensor on each wheel like the front does, its controlled by the speed sensors located on the output shaft of the transmission, and on top of the rear differential, which the sensor on the rear is where your vehicle speed is read from. from what ive experienced when that sensor goes, your speedo stops working, and you get the ABS and Brake indicators on the dash. But ive also seen where the same thing happend, and it ended up being a wire to the sensor that was pinched off from when the truck was towed.
What DTCs (diagnostic trouble codes)come up on a code reader?(if you dont have one advance and autozone will usually read the codes free of charge) or you can try the key trick as shown below.
http://www.youtube.com/watch?v=UsDm3...layer_embedded
What DTCs (diagnostic trouble codes)come up on a code reader?(if you dont have one advance and autozone will usually read the codes free of charge) or you can try the key trick as shown below.
http://www.youtube.com/watch?v=UsDm3...layer_embedded
Is the Brake light on also or just ABS?
ABS codes are C codes (I think) so the Key trick and cheaper code readers check for P codes and will not pick them up. A DRBIII will. So a good shop could read them for you. The Auto Zones, Advanced, Etc will not check ABS codes even if they could for
liability reasons.
Back to the problem.
You have Rear ABS and Front ABS.
To check the front sensors
Under the hood there will be a plug on top of the wheel wells one on each side of the truck this is the connection of the sensor to the ABS harness.
If you unclip it and check the resistance, each one should be around 900-1000 ohms depending on where the sensor is in relation to the tone ring in the wheel bearing assembly. If one is open it probably got cut by something near the wheel.
Mine was cut by the rotor after I did my ball joints and didn't make sure the wire was fed right.
If they check out ok your rear sensor on top of the rear diff is most likely the problem, if not I would start checking proportioning valve and looking for leaks and maybe try bleeding the lines.
I don't know the resistance of the rear sensor I haven't had to change that YET. LOL
Welcome to the Forum.
ABS codes are C codes (I think) so the Key trick and cheaper code readers check for P codes and will not pick them up. A DRBIII will. So a good shop could read them for you. The Auto Zones, Advanced, Etc will not check ABS codes even if they could for
liability reasons.
Back to the problem.
You have Rear ABS and Front ABS.
To check the front sensors
Under the hood there will be a plug on top of the wheel wells one on each side of the truck this is the connection of the sensor to the ABS harness.
If you unclip it and check the resistance, each one should be around 900-1000 ohms depending on where the sensor is in relation to the tone ring in the wheel bearing assembly. If one is open it probably got cut by something near the wheel.
Mine was cut by the rotor after I did my ball joints and didn't make sure the wire was fed right.
If they check out ok your rear sensor on top of the rear diff is most likely the problem, if not I would start checking proportioning valve and looking for leaks and maybe try bleeding the lines.
I don't know the resistance of the rear sensor I haven't had to change that YET. LOL
Welcome to the Forum.







