ABS Light is On

[har01dav]

Has anyone had their ABS light come on? Thought we would first try to clean the abs sensors, but not sure how to do this. Any help would be appreciated.


Thanks.
Vince

2001 Holiday Rambler Endeavor
Roadmaster Chassis RR8R
8.3 L ISC Cummins

[Zbugsii]

Well, I have had a similar problem, but it only happens when my wife uses the microwave as we are motoring down the road. All I have to do is at the next opportunity, turn the coach off and back on again. It clears it and all is well.

At first I thought it was an anomally, but I can get it to happen most all of the time...

Strange....

[nodine]

Quote:

Originally Posted by har01dav Has anyone had their ABS light come on? Thought we would first try to clean the abs sensors, but not sure how to do this. Any help would be appreciated. Thanks. Vince 2001 Holiday Rambler Endeavor Roadmaster Chassis RR8R 8.3 L ISC Cummins

When our motorhome sits long enough for rust to form on the brake drums we get a loud squeal when we first use the brakes. Often this will cause the ABS light to come on. The next time we turn the engine off and back on it clears.

Bob

[wa8yxm]

First think you need to know about ABS is.. Odds are you don't need it.
Now it is nice. I mean when I'm on a wet or slippery road and I hit the brakes it's much better than the way I was taught to react in those cases. But if I'm on that kind of road there is a good chance I'm parked somewhere.

Now, there are sensors on each wheel.. there may be one in/on the transmission (I have reason to believe, but have never actually seen one) and there is one on the brake pedal.. (Same "Sensor"that turns on your brake lights)

One thing to check for if the light comes on is proper brake light operation... Yup, if the brake light fuse is blown, if the brake lights themselves are burned out or if the switch or wires that operate them are bad.. ABS LIGHT ON

[nplenzick]

In case the above suggestion's don't work you might check your main electrical solenoid that should be in your electrical distribution panel. When that solenoid starts to go ( and it's happened twice now to us) the abs light will come on.

[Jobert]

The ABS light can also come on as a result of a sensor being moved away from the rotor as on a bumpy road. We had an issue with this after the brake caliper recall was not done correctly. The wheel bearings were not torqued to the correct spec and on a bumby or irregular road, movement in the bearings would allow the rotor to push a sensor away. The solution, at the next stop, crawl under and pull each sensor away from the rotor and press it firmly back in. After restarting and going 100 yds to a mile, the ABS light would go out. We fought this for quite a while before it was figured out by a real sharp Tech. The fronts were the worst culprit, the bearings must be torqued to at least 80 ft/lbs to keep proper lash on the front wheel. All four of our wheels were done to a different spec, some recall workmanship. Hope this might help.

Happy Trails Bert

[dveasey]

I'll add: each sensor just slips straight out; no need to unlatch. If it will not budge, use a 6" + screwdriver to "lever" it outward. Be sure to not let it bind on one side as it comes out. You can twist it back and forth if you like.
Be sure to leave the "copper sleeve" inplace on the mounting. You can leave the wires attached. There is enough slack for this.

Once you have it out, wipe it clean with rubbing alcohol. swab the copper sleeve as well. Let it dry....then, Coat the stainless steel face with either a thin layer of silicone or electrical lube [diaelectic] grease. Push back in fully.

Test drive and the ABS light should disappear.

[wa8yxm]

Oh, one other thing that fires up that ABS light

Low battery (system) voltage.. at least on my car
(Have not had that problem on the motor home yet)

It's the FIRST sign of a failed alternator.

[har01dav]

Thanks for all of the replies, we cleaned all of the grounds and discovered when we wiggled one of the wires on the ABS circuit breaker panel and pushed the test button several times, the ABS light went out. Not sure what that means. We did disconnect the electrical plugs and put dielectric grease on all contacts. Haven't driven it yet, to see if the ABS light comes back on, but have turned on and off multiple times and ABS light has cleared each time. We are keeping our fingers crossed that it stays off.

Vince

[flyingpop]

Vince,
Had this problem,and after 2 days of troubleshooting at Wildwood Monaco repair center in Fl., the tech finally found a bad ground connection in the compartment under drivers side elec bay where the computer/controler is located..clean and tighten grnd connections in that area..it's worked a year so far..worth a try

Jackie 2005 Cheetah

[Roadking]

My ABS light would intermittently come on and by turning ignition on/off the ABS light would reset. Eventually the ABS light came on and stayed on. I located the ABS trouble shooting manual on line and following instructions in manual and decoding ABS fault code indicated right rear sensor was open. Performed resistance check and confirmed sensor was open. Ordered a new sensor ($86.00) and had it replaced when I had my tires changed. To replace sensors on rear axle on my rig required removal of brake drums. They simply push into the holder, but you cant get at them without removing the brake drum.

[wa8yxm]

If it is a workhorse first step is to check the brake pedal to be sure it's fully "UP" as one of the sensors is the brake switch

I have to do that before I move next time

[WindsorDave]

Quote:

Originally Posted by har01dav Has anyone had their ABS light come on? 2001 Holiday Rambler Endeavor Roadmaster Chassis RR8R 8.3 L ISC Cummins

Shortly after getting underway on a 3,400 mile round trip last week our ABS light flickered for a few miles and then came on solid. Since our first stop was Cummins NW in Coburg, OR, we decided to wait and have them look at it.

As it turned out the problem, similar to your finding, was the small circuit board in the front run bay. One of the flexible conduits/looms was forced up against the board and one of the connectors by the coiled/stored air hose.

One of the service guys at Cummins NW allowed as how ABS error lights were often caused by connectors on this board. We moved the air hose and the routing of the relevant wires and the ABS light did not come back on.

FWIW

[bobsea43]

I have had this problem interrmittantly and it seems to be heat releated, i.e. ABS light comes on after using brakes more then normal, such as in city stop and go or a moderately hard brake application such as someone pulling out unexpectedly. After letting RV sit for a while with ignition off it normally goes away. I will investigate some of the solutions mentioned above. Some might be pertinent. Thanx.