Hello - this is my first time posting a problem and i would really appreciate some help. I have a 2005 explorer, eddie bauer (120k), which i really love driving. Recently, i have lights coming on in my dash: ABS, traction control and the 4wd light intermittenty flashing. I went to Advance auto parts and they were able to read the codes, a B1155 - speed wheel sensor LF input circuit failure and a B1145 - speed wheel sensor RF input circuit failure. I have replaced both wheel bearing hubs (with the speed sensors) about 6 monthe ago. the connectors leading to the speed sensors are both showing 12v at the plug. Is the problem both my sensors have gone bad? Is there any way to test these sensors. I need to get this fixed quickly since i am due for an emission test very soon and it will not pass if any dash lights are on. I am a avid DIY'r but have no experience with wheel sensors. I would really appreciate any help anyone could give me in this matter. thanks shadester

 

Electronics behave strangely when they experience low voltage..

If you have not replaced your battery since 2005 it is nearing its EOL.
Check the condition of charge, load test, clean all terminals and your issues MAY go away... Philip

 

thanks for the reply but i replaced the battery last summer. The terminals all look good and it starts with authority. Just in case, i will have it checked out. shadester

 

went to autozone and the battery checks out ok. forgot to mention that there is a 'check advancetrack' display in the message center. shadester

 

The Check AdvanceTrac indication could certainly be due to the issue the ABS system is reporting. AdvanceTrac relies on the ABS system as well as some other inputs.

If you know someone with a professional scan tool and the ABS software new enough for your vehicle, you could hook it up and monitor the wheel speed sensors in real time to see how they behave. Maybe that will give you an indication of the issue. For example, maybe you'd see at slow speeds that every so often the speed at one of the wheels jumps erratically. That would indicate either a missing tooth on or crack through a tone ring.

Beyond that, you'd probably need an oscilloscope and decent back probe adapters to monitor the wheel speed sensors with the vehicle safely supported and wheels removed to make sure the signals are appropriate.

-Rod

 

I added an <b><big>Autel MaxiDiag Pro MD801 OBD-II Scan Tool</big></b> to my arsenal a couple of months ago (transmission issue), worked as well as snap-on's costly scan tool (without buying all the chips)....

Will do Engine, Transmission, Airbag, and ABS. .... Philip

 

I hear ya! I used to use an OTC Genisys until I got my new car. Then I found it was cheaper for me to buy a new Autel DS708 than it was to upgrade the software in my OTC to work with my new car. And the Autel came with 1 year of included updates, but unlike OTC, the updates are for all models (domestic and import) as well as all systems. On top of that, the Autel has more diagnostic functionality built-in than the OTC (such as being able to program keys and modules).

Oops, I'm derailing this thread. But I'm another satisfied/impressed Autel customer.

-Rod