rickf

I have a ABS and brake light on problem. The lights will go on and then go off, no rhyme or reason to it. No pattern. I can pretty much rule out the wheel sensors due to the fact that it will happen while sitting at idle. Lights on and then off, again, no set pattern or timing. Of it were a sensor the vehicle would have to be moving for the sensors to be read. I have unplugged and checked every plug related to the brakes and some that were not including the main harness. I am on a low income and heading towards disability very shortly so I cannot afford to give a dealer a couple hundred dollars just to hook a scanner to it. Any ideas are welcome. Remember, the wheel sensors are two wire so no movement, no signal.

gorms

Does the truck have rear wheel anti lock only or 4 wheel anti lock?

Easy checks for 4 wheel anti lock is to check resistance of all sensors for any imbalance. Checking the wires out a bit at any points where they can get worn or unclipped and damaged, near pivot points, etc. If it's RWAL only one sensor on the rear end, if 4w ABS there should be one on each front hub as well.

An air bubble in the lines is common for causing the light to go off as well.

rickf

Sorry Gorms, I did not see your reply. The thread said I had no replies. I have 4wheel ABS. I will ohm out the sensors from the unit out. Like I said, they are coming on and going off while not moving so it has to be something that can be caused while stationary. I cleaned all of the grounds as a precaution and that seems to have helped a bit so I am leaning towards a high resistance issue somewhere. Just have to find that somewhere!

KATOOM

Check the basics first. When the dash lights are on is your brakes lights on? Does the cruise control work? There is a brake light switch under the dash which will cause those lights to come on if its faulty.

SIXSLUG

Check fluid level in reservoir too...

rickf

Katoom, It is interesting that you say that. My brake lights are not on, I have checked that. I do have an issue with them taking a bit to turn off after releasing the brake. It has been that way since I bought the truck three years ago. I have a hydroboost rebuild kit that I believe will solve that problem. Are you talking about the regular brake light switch or another switch? The cruise works just fine whether the lights are on or not. I am a firm believer in going back to the last thing you did before the problem started. In my case it was adding a new trailer brake controller and plug and play harness. This was to replace a working controller so I know the basic operation is fine. The trailer brakes work fine and I have reversed everything and taken out the harness and controller with no change. I have also checked the connections at the e-brake since that will throw a light if you drive with the e-brake on. All good there also. I am going to go to the only junk yard left around here that still sells parts and see if they have a ABS controller. If the price is fair I will buy it and hope for the best. It is just not looking like a wheel sensor, I am going to ohm them out for comparison and see if one is different than the others. If I can get a helper to spin a tire I will jack it up and hook the Vantage to the sensors and see what the wave patterns look like on the sensors.

rickf

Yup, did that. I don't have a sensor for the fluid in mine.

KATOOM

Very wise.....as this approach is rarely used.
If you cant solve it by going back to square one, I know you said that you dont think its the sensors but I understand that the front ones can be quirky.

Another thing to look for is corrosion affecting batteries, battery cables, grounds, any major electrical connection, and overall battery condition. Both batteries must be the same and in good condition. The 24 valve ISB Cummins is completely electronically controlled and is very sensitive to any irregular voltage/amps in the electrical system, and will cause strange and potentially unsolvable issues since you wont be looking at the right culprit for the solution.

2Rams

I have the same problem too. Started a couple years ago and at first it occurred more often during the winter months. Now it is all the time. Sometimes when turning the steering wheel left the lights go out. I've also noticed when the lights are out and I apple the brakes it feels as if the ABS system is working as you can feel a the pulsing in the pedal. This morning I applied the brakes and the pedal was hard like when the vacuum isn't working right on power brakes on a gasser then suddenly the brakes worked normally. Watching this closely.