Brake & ABS light

[RVerdu]

I've been a lurker for some time. I've searched the threads and haven't found an answer, so here it goes...



Brake light stayed on one night, so I bought a new brake switch and replaced it according to the instructions.



All is well except when I first start the truck.

The brake and ABS light used to go out after a couple of seconds of idling. Now, after the fix, they stay on until I drive a couple of feet.

After driving a little, they both go out, and the truck operates normally, with the full functions of ABS.

No fuses are blown, no codes shown, and the brake pads and fluid level are fine.



Should I be concerned?





2005 Quad Cab CTD, 70k, mostly stock

 

[WoodChuck]

Doesn't sound like anything serious but if your like me it'll bug you 'cause it isn't normal.

 

[RVerdu]

Thanks for the reply.

 

[brods]

I had similar issues. The Brake and ABS lights would go on for a while then off. It got more frequent until they both always stayed on. The rear diff sensor resistance didn't check out, but before needlessly buying a replacement I got the codes read confirming it was a bad read diff ABS sensor.



See if you can get the ABS codes to see what the ABS controller thinks is wrong.

 

[RVerdu]

Thanks brods

 

[Vetteguy70]

I have been having the same intermittent problem with ABS light, in conjuction with the "Parking brake Red Light" on the dash. Up until last night, it would go off after a couple miles. Of course the motor was running, so I don't know for certain if the ABS pump was activating when the light came on or not... . ((Do you know if YOURS has been activating?))

NOW, even when the motor is turned off, the key is out of the switch, the ABS PUMP is running like CRAZY~ YEP! It is pumping as if the pedal was depressed in an emergency lock up situation. My concern was burning out the pump or motor, so I pulled the 40amp Green Square fuse out of the box to shut it off. I checked everywhere to see if there were squirrel chewings on wires, a ground wire missing, or whatever. No such luck. Putting the fuse back in makes the pump re-engage and pump like a crazy man. SO I have it pulled out till I get some answers on what is wrong.

Any help would be great. I live may hours away from civilization, so before I go down the mountain to a dealer and pay for something that might be pretty simple to figure out, I"d appreciate hearing from the membership. THanks in advance.

3500 4x4 Crew Cab 2003 Six Speed manual Dually Dodge. 5. 9L

 

[WoodChuck]

Vetteguy70, your problem sounds completely different than the original poster. It sounds like you have the same problem I had last September. If it is then you Need a new HCU or Hydraulic Control Unit for the ABS (basically its the computer that runs the ABS system). Another option is to replace the complete ABS unit Motor and all. Replacing the ABS computer requires the use of a DRB 3 to initialize or tell the computer what rear end and tires your truck has.