Troubleshooter: How to avoid frozen window frustration

I’m no fan of fast-food drive-throughs. They’re tremendous wastes of fuel and idling toxic emissions, but they’re also the place where most drivers find out that their vehicles’ door windows are frozen shut in winter — and often just a moment too late.

Between so many other advancements in vehicle technology and design, you might think that someone must’ve come up with a window mechanism that doesn’t lock down when the mercury drops. Unfortunately we’ll have to wait until a Canadian engineer starts gaining influence in Californian design studios. In the meantime, here are some tips on getting through the winter with working auto door windows.

Why do door windows freeze? That’s an easy one: too much moisture on the glass, run channels, or belt moldings from condensation or water leaks. The run channels (or guides that the glass moves in) and the belt moldings (at the lower inner and outer edges of the glass) are lined with a soft, felt-like material that absorbs the shocks that glass is exposed to from everyday driving and eliminates the risks of pothole breakage. Of course, those soft fibres also create a perfect moisture trap that’s in direct contact with the glass. Add sub-zero temps to this mix and you’ve got a perfect recipe for a stuck window. This same design is what causes scratches on the glass: grit gets trapped in the horizontal belt moldings and acts like sandpaper on the window.

Why not just hold the power window switch down until the window releases? Doing this can quickly damage or break the attachment point of the glass to its moveable frame and leave the window to free-fall into the door, or can even overheat the electric motor leading to some expensive repairs. In the worst cases it can even fracture the glass or cause it to explode into hundreds of small shards. And think about it: a vehicle with a window that won’t open is unsafe.

So if you want to be safe and get your double-double without leaning out a partially opened door, you’d better start with a few simple items before Old Man Winter blows cold. First, roll down each window and take a close look at each of the inner and outer moldings at the bottom of the glass. Take a toothbrush and brush any grit off. Check for tears, cracks, or gaps — especially on the outer moldings, as these problems can leave an easy entry for water. Check the bottom edges of each door to make sure any drain holes are clear.

Then get a spray can of silicone lubricating compound (no WD-40 or petroleum-based lubes), dampen a soft, clean cloth with the spray, and wipe it along the inner edges of the lower belt moldings with the window down. Grab the straw nozzle that came with the aerosol can and use it to treat the run channels on the front and rear edges of the window frame. Get the spray as far down as you can in these channels.

Finally, if your ride has an auto one-touch-down feature, make sure your finger is at the ready to shut if off by pulling up on the switch if the window doesn’t move. If you don’t do this, the motor will continue to apply force on the regulator. This feature might be handy for summer drive-through windows and toll booths, but is the single leading cause of window regulator failures in winter.