Abs issue

Piece of black tape over abs icon on dash, fixed!

 

Check the sensor wire connection at the ECU. And at any junction if it's a 2 piece wire.

 

The sensor wires run to a box, not sure what’s it’s called. Sits between brake relay valves. Follow the wires from the wheels, to the box. Air lines go the the valves on either side of the box. Wires to the ecu run from the box to the ecu. In other words, start from the rear of the Truck, work your way back. The wires run in sections, If you only have sensors on one drive axle, I think the wire going from the box to the ecu would cause both to show shorted or open, as you stated. I’m not good with electrical. I simply hooked a jumper to a battery, and used a test light on the other end, to check the wires. I did that on my trailer power wire anyways. The wires ar only $20-$30. They’re so thin and fragile. I’ve had a couple go bad on my 08 trailer, one sensor wire and one from the box towards the ecu, It was about a 6 ft section. Longer lengths can be used, and coiled up. Replacing them is a good idea, I kept one that was still good as a spare. Ended up using it, a few mos. later due to damage from a blown trailer tire. Good luck, If I figured it out, you can.

 

I had a constant ABS fault on the 379 I used to drive. The shop had the sensors off, cleaned and replaced and it still threw a fault. One day I decided to push the brake pedal all the way to the floor with the key off, then turned the key on and heard the ABS system blow air out in small spurts as the system cycled. After that the light went out. Had to do it every time I started the truck though

 

Last six of VIN and I will get the wiring diagram.