The Lemon IndexNo heat usually means low coolant, a stuck thermostat or a clogged heater core, and it can stop the defroster working.
Fix soon. If the windshield can’t be defrosted, don’t drive in cold weather until it is fixed.
Low coolant from a leak. Then: a thermostat stuck open; a clogged heater core.
Owners describe this in 3,819 complaints to the U.S. government, most often on the Jeep Grand Cherokee.
Cars owners report it on most
Complaints describing this symptom, by model, all years. Raw counts, not a failure rate: popular models get more complaints.
Model years that report it most
| Model year | Complaints | Share |
|---|---|---|
| 2006 Chevrolet Equinox | 191 | 27% |
| 2012 Dodge Avenger | 114 | 21% |
| 2002 Jeep Grand Cherokee | 83 | 6% |
| 2001 Jeep Grand Cherokee | 60 | 7% |
| 2012 Chrysler 200 | 57 | 9% |
| 2003 Jeep Grand Cherokee | 48 | 6% |
| 2004 Jeep Grand Cherokee | 44 | 3% |
| 2013 Dodge Avenger | 43 | 8% |
| 2000 Jeep Grand Cherokee | 35 | 2% |
| 2003 Ford Taurus | 32 | 3% |
| 2003 Ram pickup | 31 | 1% |
| 2011 Dodge Avenger | 29 | 14% |
Each row is that model year's record in NHTSA complaints, not the history of any one car. Share = complaints describing this symptom out of every complaint we hold for that model year (shown when the year has 50+ complaints).
Where it makes up the biggest share
2006 Chevrolet Equinox · 27% 2012 Dodge Avenger · 21% 2011 Dodge Avenger · 14% 2012 Chrysler 200 · 9% 2013 Dodge Avenger · 8% 2001 Jeep Grand Cherokee · 7% 2003 Jeep Grand Cherokee · 6% 2002 Jeep Grand Cherokee · 6%
Model years with 150+ complaints in our data and 10+ describing this symptom, ranked by share. A high share means owners of that year who complained often mentioned it.
The details
Common causes of car heater not working
- Low coolant from a leak
- A thermostat stuck open
- A clogged heater core
- A blend door actuator stuck on cold
- A failed blower motor or resistor
General causes, not a diagnosis. A shop should confirm the cause with tests before replacing parts.
Is it safe to drive if the heater is not working?
Fix soon. If the windshield can’t be defrosted, don’t drive in cold weather until it is fixed.
Get help right away if the temperature gauge climbs (low coolant).
Of the 3,819 complaints describing it, 0.8% mention a crash, 2% mention a fire and 0.8% report an injury.
What the complaints show
The parts owners filed these complaints under: visibility (34%), electrical system (30%), visibility/wiper (15%), engine and engine cooling (12%). A complaint can list more than one.
Median odometer reading when owners reported it: 69,000 miles.
Most reports by make: Chevrolet (696), Ford (532), Dodge (491), Jeep (462), Honda (194).
What owners say it cost to fix
Repair bills owners named in complaints that describe this symptom (a/c & heat, cooling repairs): the middle half ran $900 to $1,600, typical $1,100, from 130 bills.
Each figure is one repair bill as an owner wrote it in a complaint, not a quote for your car. Prices vary with the part, the shop and the year.
Related symptoms
AC blowing warm air Power window not working Water leaking inside car Mold or musty smell in car Sunroof shattered Fuel gauge not working
Quick answers
What causes car heater not working?
No heat usually means low coolant, a stuck thermostat or a clogged heater core, and it can stop the defroster working. Common causes: low coolant from a leak; a thermostat stuck open; a clogged heater core; a blend door actuator stuck on cold; a failed blower motor or resistor.
Is it safe to drive if the heater is not working?
Fix soon. If the windshield can’t be defrosted, don’t drive in cold weather until it is fixed.
Which cars have this problem most?
In complaints to NHTSA, owners describe it most on the Jeep Grand Cherokee, Chevrolet Equinox and Dodge Avenger. These are raw counts, so popular models rank higher; complaints are owner reports, not proof of a defect.
How much does it cost to fix?
In 130 repair bills owners named in complaints describing it, the middle half ran $900 to $1,600. The right repair depends on the cause.
Counts: NHTSA owner complaints whose text describes this symptom (we matched owners' own wording, then read samples to check the matches). A complaint is an owner's report, not a diagnosis or proof of a defect. Causes and advice are general information in our own words, not repair advice for your car. Every symptom · Engine code lookup