dguru

Working on a 95 with 2 wheel ABS. Fault light and brake light are on. I am looking at the factory manual and it says to ground the antilock diagnostic connector to get codes. However it does not show where the connector is, what it looks like or which pin to ground. Looking at the 4 wheel antilock section (which I don't have) it says the connector is above the go pedal and is blue or black in color. There are 2 plugs there. One is black with 2 terminals. The other is black and has 6 terminals (one is hot). I probed them all with a test light and could not get codes. I checked my 94 and it has the same 2 terminal black plug and the other plug is smaller and blue with 6 terminals.

The buzzer buzzes when you press the brake too.

Does anyone know what terminal to ground to get the ABS fault code?

BTW this 95 sure has alot more pep than my 94.


edit The blue/black 6 terminal connector is Air bag, ABS data link connector. The other plug is the service connector. So I was able to figure my question out in the schematics. However grounding these wires don't show codes.

edit 2 I found the SOB!!!! It is right next to the parking brake. They call that near the module!!!!!! Got code 10 Sensor wire resistance reading low.

Unplugged speed sensor and reset module. Got code 9 high resistance. Now a trip to the yard to get a sensor off a 1500.

dguru

I finally got to the junk yard and got a sensor. I installed it and code 10 is now gone but now I get a code 5. It seems that the ABS module only stores one code in memory. Code 5 says "over 16 dump pulses generated" Now I am stumped. Faults will clear but if I crank it and then press the brake I get a fault code 5 after a few seconds.

fschiola

Is the sensor you replaced the one on top of the rear differential? When you replaced it did the lights go out and stay out?

dguru

Yes the lights went out after I replaced the sensor and reset. The lights stayed off till I hit the brake for a few seconds. The lights came back on and produced a code 5.

Yes the sensor was on top of the diff. I also replaced the wire between the sensor and the plug on the frame.

fschiola

I would try the stoplight switch next. There are 3 circuits that it controls, cruise control cutout, ABS and of course the brake lights. They are inexpensive and come with instructions on how to adjust them once they are installed.
Also check to see if the parking brake pedal is going all the way up when released. There is an electrical switch on that pedal as well.

dguru

Park brake switch can be ruled out because it works right and only lights the brake light. Already swapped the brake light switch.

I think it is the master cylinder. If you hold the pedal it will drop slowly for a bit then the ABS light comes on and it stops. It could be the ABS valve too. Looks like the master cyl is different on diesel than gassers. I may just get an ABS valve off a 1500 and try it before I buy a new master cyl.

patdaly

dguru, I am going thru this right now with Greenie.

You will have to get the ABS valve from the junkyard, no one even has the remanned units now.

Luckily 1/2 ton up with 2WABS, the valve is the same from at least 94-99 and Vans also used the same valve.

BTW, on both of mine I have replaced the Master Cylinder only to find a faulty ABS valve. I don't mind because both had over 100K on the originals, but before I had these trucks, I had never seen one go bad.

I do have to admit I am a big boy, and both failures were the direct result of an "oh shoot" panic stop where I am sure I dented the floorpan pushing on the pedal........

dguru

Thanks

Rockauto has them but I will check the yard first. This truck is new to me. I have only tested the ABS one time on my other one. Very loud and vibrates!

I got the second one for an engine swap and want to run it a few months first. I plan to put it in my 77 crew cab F250. I have a 4BT for it but decided it would be cheaper to get a dodge for the transmission with the 6bt. I am trying to sell the step van 4bt TH400.

infidel

Remember a '95 with vac assisted brakes will turn on the warning lights if the vacuum drops too low such as when applying the brakes several times with the engine off or idling.

dguru

I suspected the same thing but it is not vacuum related. You can apply moderate pressure to the pedal without pumping and the pedal drops slow for about 5-10 seconds then stops and throws an ABS code 5. It drops about 1/2". You can barely feel it drop. Never gets close to the floor. Vacuum pump works great and holds vacuum for days(I put a gauge on it). 3-4hg drop when applying brakes and comes right back up.

Plus when the light comes on from low vacuum it will go off when vacuum comes up. Both lights come on and stay on till you unhook the batteries.

patdaly

Really? Could you post it because I looked and looked....... Was it in the electronics section then?

dguru

Problem solved. ABS valve. Got one from a 1500 for $7 and it took 5 minutes to install. No more leak down, no more lights.

Pat you can't do direct links at rockauto. You have to go through their search engine. I just looked at a 95 2500 with cummins under brake wheel hub ABS Modulator. I don't see them under 1500's but it is listed for the 2500 cummins. They are 118.79 plus a 35 core so I would hit a yard anyway.

1995 DODGE RAM 2500 PICKUP 5.9L 359cid L6 DIESEL MFI Turbo (C) OHV : Brake/Wheel Hub : ABS
RAYBESTOS Part # ABS570022 More Info
Professional Grade}
Rear Wheel Antilock Brakes (Only 1 Remaining)