School’s out and the days are warm and sunny - we’re in the summer driving season. This is the
time for road trips, camping, visiting friends and relatives, and getting out of the suburbs. In this
time of heightened vigilance, some of us are driving less, while others remain “road warriors”
making deliveries, working in the skilled trades, giving rides-for-hire, and traveling to perform at-
home services. Your car may throw you curveballs you weren’t anticipating these days, and
we’re seeing some interesting cases in our shop.
Modern cars have a few things going on even while they sit unused in the driveway. Your alarm
system uses a bit of power to monitor door and hood/hatch sensors, listen for glass breakage
and detect movement, and other voltage changes that might indicate criminal activity. The
entertainment system retains your radio presets, time and other bits of information so it wakes
up ready to go. If you have keyless entry, proximity sensors are on alert for your approach so
you don’t need to hit the remote, but that requires a little voltage. Your assorted computers, too,
have millions of bits of data about altitude, temperature, driving habits, engine performance
stats, and other things that ensure your car runs efficiently. These devices need some power.
Ordinarily, you drive your car nearly every day, so your battery has plenty of capacity to support
these systems while the car is parked. But if you’re suddenly working from home, Zooming
instead of gathering and having dinner in your recliner instead of your local diner, your car is
depleting the reserve capacity of its battery. Your alternator quickly restores the power you use
to start your car, but if you drop the voltage too far, you may not recharge it enough with a quick
run to the mini-mart. Have you jump-started your car recently? You’re not alone. Under the
best conditions, your battery could last four or five years, but the life expectancy varies wildly
with driving habits. We’ve had many cars in the shop with bad batteries lately.