ABS Lite Stays ON after brake job. '99 Dodge Van

[floridacruizer]

I did a front end brake job. Calipers, Pads, Lines, Turned Rotors and etc. Flushed the complete system (front & rear with new fluid). Everything fine for about 300 miles. Went out today and started the van up and the Brake Lite and ABS lite came on and stay on. Can someone help me with what to do? This van has disc. on front/drums on rear. It is a B-1500 van. Thanks~~~~~~Ron

[DANVAN]

Mine is on to. I have rear ABS only. I pulled the sensor and cleaned it, but it didnt help like it did in the past. I was thinking about making a post about mine, so maybe together we can find out what the cause is. Good luck

[floridacruizer]

Dan: What did you mean when you said....you pulled the sensor off and cleaned it? Where is it located and how did you clean it? My van is also....rear ABS only. I read somewhere, that if you rebleed the brake system that it would reset the computer. I'm going to try it next week. I flushed the whole system and bled all 4 wheels when I did the front brake job. Maybe...there was a slug of air in the rear and it finally worked it's way to the sensor. Worth a try!!!!~~~~~~~~~~Ron

[DANVAN]

I dont think bleeding will help. The rear sensor is in the top of the rear end, 1 bolt holds it in. A few times over the years the light has come on. Ive pulled the sensor, cleaned it of, put it back in and it was fine, the light went out. I think 1 time I had to disconnect the battery, which I didnt do this last time. So I guess I should do that before spending money.
Flushing the brake system w/ fresh fluid is a good thing to do, but I doupt it will help the ABS system.

[Dodgevanman]

If cleaning the sensor doesn't help, then you may have to replace it. I thought you had 4-wheel ABS

[van-nut]

The ABS sensor, like DANVAN said, is on top of the rear axle, in the center. What is senses is wheel rotation only, and it is not plumbed into the hydraulic system.

If everything was fine before the brake job, and now the light is on, I bet you have a small amount of air stuck in the system (since you mentioned changing the calipers). Part of the factory recomended bleed procedure is to bleed a component called the "combination valve". One of its functions is to detect a pressure difference between the front wheel and rear wheel circuits, which would indicate a leak or failure somewhere. If some air gets stuck in the combo valve, it could cause the light to come on.

So, if you have not bleed the combination valve, try that. It should be located somewhere down under the master cylinder. Follow both brake lines from where they exit the M/C and they should go right into the combination valve. There should be a bleed screw on the combination valve - it might have a rubber cap on it.

Pete

[floridacruizer]

Rebled the system today. Didn't help!!! Followed lines from M/C to combination valve. Rubber cover but no bleeder screw (looks like a pin you could push in). From the combo valve...the rear brake line runs to another valve with a rubber plug (pulled rubber plug and it is just a deep hole). From this valve...a line comes out and runs to the rear brakes.

Lites (brake & ABS) are on and took it out and test drove. It will lock up all 4 wheels with no pulling on dirt (all brake evenly). HERE'S SOMETHING NEW after the lites came on....the speedometer won't start working until I get up to 18-20 mph. than works perfectly. When slowing down....as soon as it gets to 18-20 mph. it drops to 0 mph. What about the ABS valve on top of the rearend...does this also determine the speed for the speedometer?

All input appreciated!!!!! Thanks.........Ron

[floridacruizer]

What does it mean to clean the ABS Sensor? It appears as one bolt holds it to the rearend. Does it (sensor) go down inside the rearend? If so......What are you looking for to clean? Thanks.............Ron

[van-nut]

Well shoot, Ron! I guess that's what I get for trying to sound like I know what I'm talking about. :o

I looked thru my '98 manual and it made reference, more than once, to bleeding the combo valve. Plus it seemed pretty probable that since you had the front calipers off, you might have had some air still in there. Sorry Bud.

I have not taken my sensor off, so far at least, but yes, that sensor on the rear diff does actually do two things - from the signal it generates, it acts as both a wheel speed sensor for the rear ABS, and also feeds this same signal to the speedometer for it to operate.

Pete

[DANVAN]

Pull the sensor out of the rear diff, and clean the crap that builds up on the end of it, u will see what I mean once u remove it.

I pulled mine again this weekend, it was already clean since it hadnt been driven all winter/since last time I cleaned it. But at the same time I disconnected the battery for 10 minutes. Reconnected the battery and the light stayed off even after a quick roadtest.

Over the years Ive had to clean my sensor a few time to shut the light. This was the second time I needed to disconnect the battery. Hopefully the light stays off.

[floridacruizer]

Cleaned sensor today!!!! Didn't help....ordered new one should be here within a week.~~~~~~~~~~~Ron

[DANVAN]

Try disconnecting the battery. Let me know the cost of the sensor.

[floridacruizer]

I disconnected the battery for about 30 minutes while I was fooling with the sensor. Put it back in and didn't help. I ordered a new sensor from a Dodge Dealer in Kansas City, MO for $37.14+$10.00 shipping TOTAL $47.14. My local dealer wanted $66.00 plus tax. http://allchryslerparts.com/ Jack Miller Chrysler/Dodge. I'll post later when I get the new part.~~~~Ron

[DANVAN]

I just spoke w/a vanner friend in Pa today, he had to replace his sensor too, said he paid about $30.00, this was last year, on his 98.

[floridacruizer]

I'm sure your friend found a part for $30.00. I too could have bought the same part from a discount parts place for $26.00. I purchased my OEM part from a bonafide Dodge Dealer.~~~~~~Ron

[DANVAN]

Well, my light came back on again, I bought a new sensor from the dealer, $60.00 and the light is still on. Now I have the module disconnected.

[floridacruizer]

Finally got the new part and installed it. Lite is off and everything working OK. Problem with getting the part was...apparently~~~~~my '99 Dodge Van was at the end of the run for '99 and they stuck in a 2000 Van Rearend. The '99 part ordered was completely different from the one I ordered for a 2000 Van. The part for the 2000-up was a perfect match. If you check the application...it runs from 1997-1999. Than it goes from 2000 up!!!!

One of the ways you can tell if your sensor is bad.....your speedometer will not work until it hits 20 m.p.h. When you're slowing down....when it gets below 20 m.p.h. it drops to 0.

Happy Vannin~~~~~~~~~~~~~~~~~~~~~~Ron

Looked under the hood at the spec sheet and it says my rearend is a DRA Chrysler 8.2. Anyone know how to read what year it is for?

[bobo35]

Dodge uses this same set-up on the Dakota trucks where the abs sensor sends info to the speedo. About half the guys that replace them find that the wiring to the abs sensor has gone bad and fixing the wiring solves the problem.

Bobo35

[DANVAN]

Where does the wiring go bad?

[bobo35]

At the connection to the sensor. Usually gets very frayed there. All the Best. SW