Skip the auto shop - Our mechanics make house calls

Q: Air conditioning only blows hot air after having a blown and replaced fuse

asked by on

I accidentally shorted the wires in one of the vanity mirrors, after which all interior lights went out and the air-conditioning lost the ability to produce cold air.

I replaced the blown fuse (number F49, which is listed as being for the airconditioning ECU as well as the various courtesy lights) and the interior lights came back on, but the aircon still only blows hot air.

I looked at the fuses that according to the manual are related to the air-conditioning, but the ones I checked looked fine.

My car has 57000 miles.
My car has an automatic transmission.

A: Hi and thanks for your question. In the A/C...

Hi and thanks for your question. In the A/C circuit to the compressor clutch from the switch, there is an inline fuse. Check continuity from the switch to the clutch on the compressor. If you have high resistance or if the meter reads out of limits, then the wire has a break in it. Find the break and fix it. When shorting wires, electricity will find it least past back to the battery so check all of the circuits that relate to the connections that you accidentally shorted. If you need further assistance with the wiring, then seek out a professional, like one from YourMechanic, to diagnose the electrical issue in person and move forward with correct repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Electrical issue with window

Hi there. If you are still unsure after testing both components, you could always make a switched jumper wire, or use a circuit tester that is capable of acting as a switch. This way, you can avoid having to buy...

Q: Why why does the check engine light come on but runs fine until it gets to 2500 RPMs then it stutters

Hi there. It is possible that you could have a bad camshaft or crankshaft position sensor. These sensors keep track of the timing of the engine and send signals to the vehicles PCM. If one of these sensors fails, the...

Q: When I take off the A/C stops coming out of the vents

Hello. If this only occurs under acceleration then there is a problem with the vacuum hose routing for the A/C blend doors. Most of the time it is because the reservoir under the hood is failing or the check valve...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...