BSM Unavailable Error - C1AC2

I just took my Tacoma up through heavy snow for the first or second time. A few days into the trip, I got a warning on the dash that my Blind Spot Monitoring was unavailable. The next day the message went away, but a day later it returned and has now stayed on.

I pulled the DTCs and it shows C1AC2 ("Slave Module Horizontal Axis Misalignment"). I've found several threads about issues with the BSM system, but most don't mention that specific DTC. As my error code is specifically about an alignment issue (and not one of the DTCs related to lost communication with the module) I don't think my issue is wiring or corrosion related as some others have reported.

Is my assumption that this isn't a wiring/corrosion issue sound? How does the module know it is out of alignment? Is there a way for me to reset it myself?

 

Here’s the procedure, not sure if it’s a do it yourself thing or not.

 

How does the sensor know it is out of alignment? Does it have a inclinometer in it? What could have made it come out of alignment?

 

Did you get any debris under the bumper caps?

Try spraying off/cleaning the sensors, turn off BSM, disconnect battery for over 15 minutes, reconnect, start truck, turn ON BSM switch.

 

That's what I'm wondering. I washed things out, but perhaps there is something stuck under there. Would debris be enough to push the BSM module out of alignment? Once out of alignment, can you physically get the sensor back into alignment and things will start working, or does it have a "memory" and have to be re-calibrated with techstream?

 

This guy has a lot of knowledge. Maybe PM him? This thread has some info too. Also, ttry cleaning and resetting as I suggested in my last post.

 

Post 88 of the linked thread:

BTW, have both sensors if you need

 

Holly hell. Dropped it off at the dealer and they want $4000 to fix it. Is this something an independent shop can do, or is Toyota the only one with the necessary tools to do it?

 

What is the issue? $4000 to fix what and how?

 

There is a TSB that says when the module reports a C1AC2 DTC "Slave Module Horizontal Axis Misalignment" they have to replace both modules and re-calibrate everything. $1000 ish in labor and another $3000 in parts. I can order the parts directly from other Toyota dealers for $1600 and can find what I assume are legitimate new modules on ebay for $260/pair. I know exactly what the procedure is as it was linked to above, and it's 60 minutes of work, so I'm not included to pay this dealership $1000/hr in labor nor $2750 in parts profit.

I would do it myself (cheaper to buy a legit subscription to TechStream) but I lack the special reflector tool that is required. I'm wondering if this is something other independent shops are likely to have such that I could jstu take the truck and 2 new modules to them and pay the $150/hr or whatever rate to have them run through the install and re-calibration.

 

SsT is that small triangle reflector.
You could make one easily. It's about 4"