2009 f250 code c1175 (left rear wheel speed sensor input circuit failure). the only rear sensor it has is in center on rear diff. this has been replaced. what is my scanner trying to tell me.

 

Your definition is incorrect for a C1175 for your specific vehicle. It should read "Wheel Speed Sensor Rear Input Circuit Failure" with no reference to the left side.

The scanner is telling you that the ABS module isn't seeing a valid signal from the rear sensor. That means it might be the sensor, the wiring or the ABS module. You have to do the diagnostic procedures unless you just want to guess and hope you get lucky.

 

narrowing it down-replaced sensor and wiring. guess that leaves abs module. note scan results from snap-on scanner

 

note that it appears that you didn't do any of the troubleshooting and that you're guessing...

 

I'm surprised that a Snap-On scanner didn't tell you more than it did.

 

to projectsho89. it is a shame that you expend the time to criticize someone else's attempts to learn and expand their basic knowledge of autos. you know , unfortunately we can not all possess the expertise and knowledge of an obviously certified mechanic like yourself. however if all you have to offer is criticism, maybe you would be better off keeping it to yourself. or maybe you should read your last line

 

A SnapOn scanner is a professional-grade tool. It should be used by professionals who actually know what they're doing... If that description doesn't fit you, then your name-dropping of the tool's brand has led the reader(s) astray into thinking you're a professional when you are not.

Good luck.

 

i work with a group of ASE certified mechanics. this issue came up in the shop, and i volunteered to throw this thing in the pit.it is well known that this year f250sd only possesses one sensor, in the diff. two in front. it was a wtf question. we are going to ask sales rep when we see him.

 

That a bit harsh, don't you think!?

 

yes, but consider the source

 

By all means lets consider the source---and what do we consider exactly? I'm NOT defending projectSHO89 as he doesn't need my help so I'm simply commenting. While his succinct and direct comments might seem harsh or mean-spirited to thin-skinned folks he's not wrong in anything he's contributed to this thread. If "we" don't like what we're hearing or reading its typically because it hits a bit too close to home.

I'll fully agree mentioning a Snap On scanner would imply there's some sort of expertise associated with its use and yet OP is still fumbling for an answer to his problem, has seemingly ignored the help and suggested direction to take resolving this speed sensor issue. So now we're talking about unrelated issues without making any progress towards fixing anything.

I've been taken to task by many here for my own missteps and yeah they sting a bit BUT in the end it's served to make me slightly better at working on my Ford vehicles. I joined FTE to learn and be helped or help so however I get there is part of the process even if my toes are lightly stepped on from time-to-time. Often times I see my mistakes boil down to not providing better information OR ignoring what's offered as help---that failure doesn't fall on those reading or commenting on what I've posted--garbage in, garbage out.

So SkeetsF250---have you resolved your original issue so far? Please keep us updated if you would.

 

problem was in wire harness . fixed and done last year. completed before thread initiated. the initial question,still unanswered, is why our scanners were indicating a circuit issue with left rear sensor, when there is no such thing.apparently my intro was too ambiguous to be understood. maybe (why are our scanners indicating a problem with a part that does not exist) would have been understood and accepted. however why the question of our capability as a certified shop was approached is beyound me. happy new year jwa. note at 74 this not the first time my ability has been questioned.

 

@skeetsf250 I have found similar situations (not just in automotive diagnosis, but in other interfaces where standard protocols are integrated with a pre-established set of parameters or descriptors, and where an arbitrary or automated association is made based on "best fit" or "closest fit", rather than on a precisely tailored, individually specific description for the exact scenario).

In this case, if the rear abs circuit is faulty, and there is only one rear abs sensor, and the pre established parameter data set has a provision for both left rear and right rear abs sensors... then it doesn't matter if the fault reported is associated with left rear or right rear. The diagnostic solution is the same, as there is only one circuit, leading to one sensor. So the software must pick a parameter to report. Left comes before right, so pick left. Or pick right, it doesn't matter if there is only one.

This is more likely to happen with scan tools that cover a variety of brands of vehicles, where even though the scan tool manufacturer may have licensed the proprietary diagnostics from each vehicle manufacturer they claim to cover, they may not necessarily rewrite a new interface that is distinct for each vehicle manufacturer or model. Since other models and manufacturers do have individuated left hand and right hand rear ABS sensors, then on vehicles with only one sensor for both, the scan tool picks the left rear sensor circuit to report, because the diagnostics and solution is the same, as there is only one circuit. It's as if the software integration engineer had to simply pick the best fit, or closest related parameter to report. Left comes before right, so pick that. Either parameter will work, as both indicate rear, and there is only one rear for the vehicle in question.

It has been 18 years since I used an MT2500, so I don't remember any longer what that interface is like. On my old Ford, I use an NGS, and it says Rear, not left rear or right rear. But I have 8 different PCMCIA cards that I need to swap in and out of the NGS to change the NGS personality and function for the 25 years of Ford vehicles that it covers. So the software is more specific to the particular Ford vehicle being diagnosed. And the NGS will not do chassis diagnostics for Chevrolets, as an example, while the MT2500 covered GM, Chrysler, Jeep, Ford, etc.

 

Y2KW57- Thank you so very much. This is the intelligent reply that we were looking for. This gets the rep off the hook ,and allows me to return to to the shop tomorrow with an intelligent answer to our question. This is the quality response that I was expecting from such a varied and experianced group, such as this forum. Again thank you very much for your time and expertice. Have a Happy and Healthy New Year