When no air comes through the vents, the blower motor, its resistor, or a blown fuse is almost always the cause. Here are the most likely culprits ranked by how often they actually turn out to be the problem.
The resistor controls fan speed. When it fails, you often lose all speeds except high, or all speeds entirely. A $20-$60 part.
The blower fan itself burns out, especially if it has been making a whirring or grinding noise before quitting. Behind the glove box on most cars.
The simplest and cheapest fix. Check the HVAC blower fuse in the cabin fuse box first - takes 30 seconds.
A filter packed with leaves and debris chokes airflow. You may still feel a trickle on high but nothing on low. $15 fix.
The dash control unit fails to send a signal to the blower. Symptoms include unresponsive buttons or stuck mode flaps.
You smell burning plastic or electrical odors from the vents, see smoke from the dash, or the fuse keeps blowing. These point to a wiring short that can cause a cabin fire.
Tell us your symptoms and any codes you have. AmpAuto's AI cross-references NHTSA recall data, common failure patterns, and your exact year/make/model to give you the most likely cause - free, no signup.
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Parts are $60-$220. Labor is usually $120-$280 because the glove box has to come out. Total $200-$500 at a shop, $80-$220 DIY.
The blower motor resistor has failed. It controls low through medium speeds, but high bypasses it and goes direct to the motor.
Yes, but defrost will not work which is unsafe in cold or humid weather. Fix it before winter.
No. The blower motor moves cabin air. The AC compressor cools refrigerant. You can have one fail without the other.
A bearing seized or debris (leaves, acorns) jammed the fan. Sometimes clearing the squirrel cage gets it spinning again.