After correcting a reversed wiring in the ABS warning light circuit, a factory error that has kept the ABS warning system from functioning for 11 years, I found that both drive wheel sensors were showing faults. Further testing showed both to have open circuits.
I believe Steve has posted photos of him replacing the front ABS sensors, something that can be done with only mildly superhuman effort. Drive wheel sensors are another matter and not something easily accomplished by an individual owner. So, off to the experts at Colton Truck Terminal Garage in Colton, Ca.
Replacing the drive wheel sensors requires removing the dual wheels, the disk brake caliper, the drive axle, and the hub. The attached sequence of photos shows the various stages of the process.
Cost to do both sides is about $1000 (more or less, as I have yet to receive the final bill).
I really like what I have seen so far here at Colton. They are doing the work outside (after all we are in sunny southern California) so we can stay in the coach. And they let me watch and they explain what is going on. And they seem to know what they are doing.
Jim,
We had a fairly good experience there last year. Though I would have much preferred to do all the work they did (baseline service changing virtually all of the fluids, filters, dryer service, etc. and a front wheel seal replacement), I didn't have a place to do the work so I talked to Barry B. and got a good report about them. The day we went, there were two other Foretravels there, so I had a good feeling going in. ^.^d
What is the techs name who did the work on your coach? I am trying to remember the name of our tech, but it is escaping me at the moment...
Don
Two techs have been working on my coach. Mike is the journeyman with 27 years experience and Daniel is his helper with 1 year. Daniel did the wheel sensor work with supervision from Mike, Jerry, Bobby, and Ed. Ed, the foreman with 35 years, carefully checked all Daniel's work and guided him along. He was very patient with Daniel to show tricks of the trade. Daniel is quick to learn and a pleasant young man to talk with.
I hope I continue to be pleased. I always hold my breath when having anyone work on my coach. But, so far, all is well (finger tightly crossed).
Jim,
Thanks for the photos and details. That is a lot more involved than the steering or tag sensors, thats for sure.
Interestingly my drive wheel passenger side abs sensor "errors" from time to time with a low voltage note on the VMSpc. Having that replaced sooner rather than later is something I need to do!
Good post Jim. Lots of work involved in doing that.
Like Steve, I also am getting a VMSPC code once in a while that says " wheel sensor ABS axle 2 left. Low current. When it says left, does that mean drivers side or passenger. What is the reference point?
I would not worry about transitory ABS warnings from VMSPC. If there is a true fault in the ABS system, the ABS ECU will turn on the red ABS error light and keep it lit. I do not know the logic used in VMSPC to indicate an ABS fault, but I suspect it is not as thorough as that used in the WABCO ECU. Bad data transmission on the data bus monitored by VMSPC can result in a transitory error indication.
You can, also, have a tech run the WABCO Toolbox diagnostic software to test the ABS system.
I believe that should be drivers side, drive wheel .. front axle is 1, drive 2, tag 3, right is passenger, left is driver ... but if the ABS light comes on you can go through the dash blink code routine to be sure.
Mine lights up and stays on when I get that VMSpc error code, I only look for the codes when I get the dash light. I can reset it and it will be fine for a few trips but it will come back on. Our ABS system has always been a bit particular anyway, its kind of our Big Bang engine light.
I've never had the ABS light on the dash come on, other than when just starting and durning the self check.
Thanks Steve and Jim for the info.
Sometimes if I stop at a rest area or a delay at a traffic stop the abs light will come on, but if I turn off the ignition and restart and as soon as the coach starts to move the light goes out, think it may be related to temperature as seems to happen more often when the temp is warmer
My ABS light comes on every time I turn the ignition on. However, once I start moving (I guess about 3-5mph) it goes out and never comes back on...until the next ignition cycle.