Oakes: Simple solutions to winter impact on ADAS

Mother Nature missed the "solstice memo" and continues to drive snow, sleet and frost our way. Winter can be cold-hearted to technicians performing calibrations on advanced driver assist systems (ADAS), presenting unique challenges to be serviced.

A successful modification becomes a creative balancing act based on snowplow schedules, new potholes and other winter hazards. It doesn't take a big storm to impact those non-photographic moments, either. You might as well hang-up your (calibration) targets if Mother Nature decides to add flurries as "dust" covered lane markers will quash the simplest component reset.

There are steps, though, you can take to fight back.

First: Wash the car.

Unfortunately, vehicle owners do not visit their local car wash in winter as often as in warmer months. The "white-paste" on the sides or rear of vehicles can create a possible false-positive to the ADAS calibration process. That is nothing but good old-fashioned grime and other snow-infused chemistry embedded into the paint.

The filth does not stop at the quarter-panels, as it can build up barriers on any exposed component and could be a reason for ADAS failure.

These are a few of the major things to inspect before performing a calibration:

• LiDAR, SEDAR (Light Detection and Ranging, Spectrum-Enhanced Detection and Ranging): This "Moon-mapping" module can be fooled by snowfall (or rain), but more importantly its location in the front end of the vehicle leaves it susceptible to a barrage of whatever liquid is covering the roadway. Again, de-icer, road salt, automotive fluid chemistry mixed in with the water-based assault.
• Infrared-Electromagnetic RADAR (or EMR) working with cameras has a challenge when it comes to identifying temperature wavelengths during winter weather events; a difficult task to handle while in motion along with winter slush thrown from the tire treads of vehicles ahead.
• Proximity sensors: Although time-tested and reliable, these can be fooled into giving the wrong information if there is a coating of road dirt covering the bumper "dots." (Remember, there are specs for body shop paint coatings based in millimeters for these sensors. Road dirt is more robust than a thin layer of color.)
• RADAR and ESR (Radio Detection and Ranging, Electronically Scanning RADAR): Right now, everyone — except Tesla Inc. — is betting on RADAR as the most reliable sensor out there; ESR maybe the new choice of the future. Many models have placed this sensor behind the "glass-like" emblem on the grill, and it also is subject to the onslaught of winter weather by collecting within the decorative cavity.

No matter how well you clean sensors and lenses, there is another evil lurking within the winter mix: corrosion. "Pigtails," chafed wiring and wiring that has had its insulation test-pierced (shame on you who do this dated practice) can be assaulted easily by the elements and set up a micro-oxidation shop right in front of you.

All it takes to clean this up is a 2% drop — in most cases — to create a false-positive. Do yourself a favor and verify electrical integrity visual (e.g., pigtail integrity) and electronically before calibration. It may sound like overkill, but when you do find and issue, you're going to thank yourself for taking the extra effort on the front-end and saving hours chasing your tail in diagnostic mode.

Now, let's talk about damaged sensor-mount brackets. The vehicle's nose and windshield are tough customers; debris striking the front of the vehicle can damage ADAS components.

Some don't believe that this is such a big deal, but impacts hit the vehicle at a higher speed than traffic. Say you're cruising the neighborhood at 30 mph, the outer diameter of the tire is spinning approximately 562 rpm on the average vehicle. Any object thrown out of a tire tread is flying towards your vehicle at around 50 mph. That's 20 mph faster than your cruise speed. It creates the possibility of an object damaging an ADAS sensor or bracket which would alter the geometry.

What's the "quick check" to see if this is the case on the vehicle in your bay? Invest in various-sized electronic levels (don't rely upon your phone app). If something isn't quite plumb, take a closer look and verify.

Then, there are those obstacles the driver encounters while trying to avoid that ice-sliding, loose-traction vehicle ahead.

If a car or truck's steering gear-suspension is stressed beyond its mechanical design, the alignment integrity most likely will be compromised.

With ADAS — along with camber, caster and toe being within spec — the thrust angle is key to the vehicle's rolling down the highway within 1 degree accuracy. Alignments must be verified before any calibration and documented.

ADAS-equipped vehicles have a significant amount of machine learning software. Don't forget to check for any recalibrations — "over the air" (OTA) or physical "handshake" on the manufacturer's site — before picking up the scanner and perfecting any sensor/module setting. For the time being, don't get caught up in the shop production rush and forget the base of ADAS before pressing the "OK" button. Snow or no snow.

SME Pam Oakes has been embedded within the automotive industry for more than 30 years as an automotive applications engineer, instructor and course developer, 609 instructor/test proctor, automotive business strategist, 20-year original start-up shop owner/multiple auto business owner, ASE Master automotive & Medium/HD truck & Collision technician-trainer w/L4 ADAS, Diesel Class 8 instructor, ASE testing contributing panel member (L4/A7).