Today’s automotive electronic systems are far more complex than in the past.

In just 10 years, we’ve made giant strides in automotive electronic systems. Without wanting to discourage you, these changes require updating your training and diagnostic equipment to keep pace. And there’s no indication they’ll slow down, as manufacturers continue to improve performance and driver assistance systems in their new models.

Recently, our shop received a small sport utility vehicle with an intermittently illuminating malfunction indicator light on the dashboard. The SUV in question was equipped with a blind spot detection (BSD) system. The malfunction indicator would light up one day, but not the next.

Why was this mechanism functioning so erratically, when the customer had just taken possession of the approximately five-year-old used vehicle, claiming everything had been fine since its acquisition?

A system that doesn’t like rain

After a series of tests and a road test, we realized that, oddly enough, the problem mainly occurred on rainy days. The blind spot sensor, located behind the rear bumper, was defective. The bracket holding it in place was very slightly damaged, affecting the assembly’s water tightness.

This sensor had thus been exposed to water for an extended period, which had corroded it. This explained why the problem only manifested on rainy days, and several months after taking possession (following the winter cold).

Fortunately, the customer was able to reach an amicable agreement with the car dealership that had sold her this vehicle, which had supposedly been repaired before being put back on the market.

Challenging conditions

Every vehicle, regardless of make or model, from the modest subcompact to the largest pickup truck, is designed to have a certain useful lifespan. In our case, in Quebec, these vehicles face a harsh climate that puts their capabilities and endurance to the test.

Moreover, calcium and sodium are the worst enemies of electrical components. Wire corrosion can cause a multitude of electrical problems, and even lead to a breakdown or malfunction of an important safety system.

A situation of this nature, recently diagnosed on a hybrid car in our shop, proved to be the source of significant problems.

I therefore encourage you to take the time to methodically perform your tests to find the true source of an electrical or electronic problem. This way, you can provide accurate information to your customer, whether it’s a perceived problem or one that’s yet to come.

Happy diagnosing, everyone!