When your defroster stops working, reduced visibility can lead to hazardous driving conditions.
Sometimes, turning on the defroster may also automatically activate the air conditioning.
If the coolant is low, fill it up.
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Check the heating, ventilation, and air conditioning (HVAC) controls.
If you have vacuum-activated controls, there may be a break in the vacuum lines.
verify if it’s possible for you to hear the blower motor running.
If it’s plugged, clean it.
If it isn’t, the blend door may be stuck, or the vents may be plugged internally.
Check for power at the blower motor.
If you don’t hear the blower motor running, then check for power.
It’s always possible for a switch to go bad as well.
When a rear window defroster goes bad, the repair is typically either expensive or time-consuming.
Here’s how to fix a rear car window defroster:
Check the defroster grid.
Some grids can be repaired, but you may need to replace the back glass.
Check the spade connectors.
Most defroster grids use spade connectors to provide power and ground, and they sometimes come unplugged.
If the spade isn’t broken off the window glass, have a go at reconnect it gently.
If you could plug it back in, the defroster should start working.
If it works, you may be able to put off an expensive repair.
If nothing else works, you’ve got the option to also check into 12v car defrosters.
What Causes a Car Defroster to Stop Working?
In contrast, rear defrosters typically rely on a grid of hot wires affixed to the window glass.
There are exceptions, but you’re able to find these types of defrosters in most cars.
