[bruginator00]

I am working on a 95 12valve and the ABS/Brake were on constantly. The brake lights didnt work and blew a fuse everytime i touched the brake. I looked and found a broken power wire to the trailer connector. I fixed this and now the brake lights work and the fuse is good. But when i drive it, at about 40 mph, they kick back on and don't go away till i shut the truck off and restart it. I've been researching and can't figure out why this happens when the truck hits 40 mph. Any help is appreciated. Thank you

 

[DM1970]

I am working on a 95 12valve and the ABS/Brake were on constantly. The brake lights didnt work and blew a fuse everytime i touched the brake. I looked and found a broken power wire to the trailer connector. I fixed this and now the brake lights work and the fuse is good. But when i drive it, at about 40 mph, they kick back on and don't go away till i shut the truck off and restart it. I've been researching and can't figure out why this happens when the truck hits 40 mph. Any help is appreciated. Thank you

Take the ABS sensor out of the rear end and clean it. Worked for me

 

[flubyux2]

+1. My abs light comes on and stays on everytime. But my Brake light is random and intermittent. I have a feeling it's the sensor under the master cyl but it appears to be kosher.

 

[npe3484]

Mine are both intermittent. Sometimes they'll both be on, other times it'll be one or the other. So far I've replaced the brake light switch and the rear ABS sensor with no luck. Mine seems to happen more frequently if I accidentally spin the tires on wet roads.

 

[flubyux2]

Oh, then that's normal. It's a chronic issue with 24v trucks. The abs system is a Nazi when It comes to wheel spin. Theres an actual code for it and everything. It just happens. Especially for those guys who take their trucks off road. When I had my 02, it would throw a code for it when I would take it off the pavement /median to turn around.

 

[npe3484]

I wonder what my intermittent brake warning light is caused by then? It never comes on with wheel spin.

 

[flubyux2]

It could be a fine metal powder stuck to the tip of the sensor that's affecting the reading since it's prob a magnetic pickup sensor. Try pulling it out (on the rear end or side of the tail shaf housing or transfer case) and wiping the tip off if you find any crap stuck to it.

 

[npe3484]

I just replaced the rear ABS sensor a week or two ago. Maybe changing the diff fluid will make a difference.

 

[flubyux2]

Don't forget you have an OSS on the transfer case. That could be giving conflicting signals being compare to the axle sensor. It might not be an issue since I heard it's onlyfor the speedo but there's always a possibility the PCM uses it to compare speed signals to the axle. I wanna say it's like $43

 

[rthouck]

I've been having trouble with my lights too - try this post - it has some wiring diagrams that should help as well

2nd Generation Dodge Cummins - Anti-Lock Braking System Diagnostics (ABS)

 

[bobjimflys]

I first used my parking/emergency brake, and soon as I released it, ABS light came on the Brake Light will not go off, brakes work okay, minus no abs, change both front abs wheel sensors, new rear differential sensor, also replaced switch that is attached to the parking/emergency brake. Still have abs light and brake light on.

 

[YogiBayer]

I thought 95 only had rear abs

 

[GAmes]

The factory service manual has an ABS troubleshooting procedure. Even that doesn't cover everything. I traced mine to an electrical connector that had water in it.

 

[bobjimflys]

This problem for me started when I was parked on a steep hill, so I decided to use my parking brake, when I released it the ABS light came on and the Brake light remained on. Replaced front wheel sensors, differential sensor parkiing brake release switch

 

[YogiBayer]

Try changing the fluid

 

[bobjimflys]

Ok, will try that idea

 

[GAmes]

The diagnostics for the ABS covers 13 pages in the '97 manual. Not one time is flushing the brake fluid mentioned, but it is probably overdue anyway and you might get lucky. If not, I recommend you open your manual and start with step one. The procedure will be in chapter 5.

 

[bobjimflys]

thanks

 

[YogiBayer]

GAmes is right. It wont hurt. Could help. I'm working from a 95 only has rear abs and that's disconnected. New fluid may raise the pedal though. Try a fluid upgrade. DOT4

 

[GAmes]

DOT 4 fluids are also glycol ether based, but have a measure of borate esters thrown in for increased immunity to water absorption. Because of this chemistry, the DOT 4 fluid will have a more stable boiling point during the early portion of its life, but ironically once the fluid does actually begin to absorb water, its boiling point will typically fall off more rapidly than a typical DOT 3. By FMVSS116 standards, DOT 4 fluids must have a minimum dry boiling point of 446F and a minimum wet boiling point of 311F.
Does this make DOT 4 fluids better than DOT 3 fluids? Not always. Remember, the boiling points listed are minimums, and there are DOT 3 fluids out there with higher boiling points than some DOT 4 fluids. The real differentiating factor should be that if you run a DOT 4 fluid you really should change the fluid more often than if you use a DOT 3, if for no other reason than the rapid fall off in boiling point with time

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